# Frustrated with builder



## kevin1727 (Aug 4, 2021)

I'm now on the second carburetor on my car. 
Rebuilt 428 engine, TH400, long tube headers, 3.36 rear end.

The car runs like an old U-Haul truck and the exhaust pipes are loaded with black soot.

First carb was a 650cfm HP Holley dual pumper. No choke and probably 4 mpg gas mileage. Smoked like a mosquito fogger.
Second carb is now an Edelbrock 1411 750cfm. Mileage is around 10mpg but still a good bit of smoke, black soot in tail pipes, and hesitation when first hitting the accelerator. 

The builder wants to try a standard 600cfm now.

My position is that if the fuel/air mixture, timing, etc are correct, then changing the max capacity of the carburetor should make little difference unless I am running at max rpm.

I can adjust the fuel idle mixture but swapping out springs and jets are not in my skill set. It's been decades since I threw out my timing light and tuning tools.

The builder says he put "milder" jets and springs in this carb but there has to be something else wrong.

I'm currently trying different accelerator pump settings and vacuum advance ports. No luck so far.

I've heard so many different things and I'm lost. 
Fuel pressure too high? -the fuel is fed from an atmospheric pressure bowl, so how is that an issue?
Too many CFM for a cruiser? -isn't cfm set by throttle position? It's not always running at 750 cfm.


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## ylwgto (Oct 27, 2009)

600cfm will starve that engine, even if it is a mild tune.

I've been battling my carb on my 400 as well. Its a Holley DP 750. Previously I had an Edelbrock that I could not get tuned right (determined to have internal issues), then a stop-gap Holley 600 (just to move it around) and now this. Therse were all second hand carbs, so I get what I ask for.

But if you have a builder doing work for you and they want to detune a 600 cfm carb on a Poncho 428, it is time to find a new mechanic.

Timing is also critical on our Pontiac blocks. There are many on this forum that have educated me to this. It is not a SBC and vacuum advance and total timing are critical to get proper throttle response, idel quality, power at WOT and fuel economy. I'll let others chime in, as I am far from an expert.

But again, if your guy is trying to soften a 600 carb to get your 428 to run proper, he or she may not be the best person for Pontiac engines...


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## Bopman (7 mo ago)

ylwgto said:


> 600cfm will starve that engine, even if it is a mild tune.
> 
> I've been battling my carb on my 400 as well. Its a Holley DP 750. Previously I had an Edelbrock that I could not get tuned right (determined to have internal issues), then a stop-gap Holley 600 (just to move it around) and now this. Therse were all second hand carbs, so I get what I ask for.
> 
> ...


That 428 should be capable of handling a 800 cfm as I have run a 800 cfm Q- jet on a stock 350 Buick !


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## Baaad65 (Aug 29, 2019)

Timing, timing and then timing first, then the carb....the carb just makes good time slips. It will run on a two barrel or a 950 dp if tuned properly, one will just be faster. Tell us about your timing.


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## armyadarkness (Dec 7, 2020)

My 400 has an 800 on it. Agree with yellow that you're way under carbed


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## kevin1727 (Aug 4, 2021)

Thanks for those ideas. I got rid of my timing light, tach/dwell meter, and vacuum gage decades ago. LOL 

Still have lots of other tools though and a good place to work on it.

The builder isn't charging me extra to work the problems, and another mechanic at this time isn't in the budget.
Guess I'm going to have to bite the bullet and get more tools.

I check the timing as soon as I get a light.


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## kevin1727 (Aug 4, 2021)

ylwgto said:


> .....
> It is not a SBC
> ...


?
Small Block Chevy?


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## kevin1727 (Aug 4, 2021)

Any recommendations for a tach/timing light?
Actron?
Innova?


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## BearGFR (Aug 25, 2008)

Somehow the idea that it's easy to have a carb that's "too big" has become gospel, but it's not 100% true. I watched an Engine Masters episode where they disproved it - on a dyno - no b.s. it might be possible if you go stupid big, like putting an 1100 Dominator on a stock VW flat 4, but anything even remotely reasonable will be fine, like was just said "if it's tuned right". Carbs work on the principle of the air flow velocity through them. That's what activates their various circuits and causes them to feed fuel. As long as your engine can generate enough flow velocity through a carb to "turn it on", it can be made to work for you. 

I agree. Get your ignition and timing sorted out FIRST, then perhaps run a compression test (or much better, a leak down test) to assess the relative health in terms of how well your cylinders are sealing, once you've gotten all that lined out, THEN think about carb tuning. 

I can attest that it makes a huge difference through first hand experience. On my previous build close to 5 years ago now, I went with an AED 850 on my 461. It literally took me 12 months to get that carb even close to being right (too rich at cruise) and to get there I had to modify nearly every single circuit on that carb. Then I discovered I had just one cylinder, 1, that had over 20% leakage. That and a rear main leak caused me to go through the engine again. Once it was back running, I ended up having to UNDO every single change I'd made to that carb to get it tuned right. 

Bear


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## BearGFR (Aug 25, 2008)

kevin1727 said:


> Any recommendations for a tach/timing light?
> Actron?
> Innova?


Judging from the photos of them I think a lot of different brands all come from the same manufacturer. Unless you spend a ton of money on one, my thoughts are that quality control is such that you're rolling the dice as far as whether you get "a good one" that's accurate and will last, or not. You can read the product reviews on any site that has those and no matter which one you look at, some people love it and some people think it's junk. 

Pick the one that appeals to you and roll the dice. 

Bear


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## Jared (Apr 19, 2013)

I'm on the you are undercarbed bandwagon too. 

I was running a 600 CFM Eddy carb on a stock block Chevy 305 and it ran great. And I mean bone stock, like maybe 200 hp on a good day bone stock. Only adjustments I made to it were going down one size on the jets and different metering rod springs. I have an 800 cfm on my 461 and it runs great. I was running a 600 on it for break in. even though I knew it was way too small, but used it anyway because I knew the carb ran good. I was pulling ~4 mpg with the small carb and somewhere between 8-10 with the bigger one that's on it now. Performance is night and day better with the larger carb.

You don't need a great timing light unless you want to get one where you can set it to run advanced for dialing in higher RPM timing. Any basic light will work.


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## Duff (Jan 12, 2020)

Lots of used, name brand timing lights on Ebay


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## Greek64GTO (Dec 13, 2015)

In regards to all the comments of timing. Don't forget, you might start by having your curve on Distributor examined and properly set up. Then, when you slap that timing light on her, she will tell the full story all away through the operable rpm selection. Good luck.


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## ponchonlefty (8 mo ago)

800 cfm is stock for most q jets. i have a 400 with a 2 barrel runs just fine. cfm is not the problem. timing, jets and reading the plugs. is how i tune. an o2 sensor could be helpful in finding the tune you need.


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## geeteeohguy (Feb 2, 2008)

Bear is one of the sharper tools in the drawer and he speaks the truth. As a retired mechanic myself, I'll say that you can educate yourself and address the issue or be at the mercy of 'mechanics' that may or may not know what they are doing. It sounds like your guy is more of a parts swapper. You need to get on line and watch some videos and crack the books and give it a go. My '67 GTO gets 21 mpg at 75-80 mpg and my '65 GTO with tripower, cam, 4 speed, and 3.36 gears gets 15 mpg. 
These cars are very basic. The ignition timing needs to be correct and the carburetor needs to be set right. With your super rich condition with all carbs tried, I wonder if your fuel pump isn't putting out too much pressure? These cars need about 4psi fuel pressure to run right and many, many new 'offshore' pumps put out 12 psi or more, causing condtions like yours.


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## kevin1727 (Aug 4, 2021)

geeteeohguy said:


> ...With your super rich condition with all carbs tried, I wonder if your fuel pump isn't putting out too much pressure? These cars need about 4psi fuel pressure to run right and many, many new 'offshore' pumps put out 12 psi or more, causing condtions like yours.


I don't understand how that works. Isn't the fuel bowl and float like the water tank on the back of a toilet? Fuel is blocked by the float, right? Water pressure doesn't make the tank overflow on the toilet.
It is a mechanical fuel pump, not a high pressure electric pump.


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## kevin1727 (Aug 4, 2021)

Duff said:


> Lots of used, name brand timing lights on Ebay


I went with a "same day delivery" one from Amazon. Yeah, it's surely made in China.


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## Jared (Apr 19, 2013)

kevin1727 said:


> I don't understand how that works. Isn't the fuel bowl and float like the water tank on the back of a toilet? Fuel is blocked by the float, right? Water pressure doesn't make the tank overflow on the toilet.
> It is a mechanical fuel pump, not a high pressure electric pump.


@geeteeohguy may be onto something here. Too much fuel pressure to a carburetor will make it flood past the needles. Edelbrock carbs are extremely sensitive to this. I believe they specify no more than 8 psi. If you are running a high flow mechanical pump, or something of that sort, you need to run a pressure regulator to meter it down.


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## kevin1727 (Aug 4, 2021)

Jared said:


> @geeteeohguy may be onto something here. Too much fuel pressure to a carburetor will make it flood past the needles. Edelbrock carbs are extremely sensitive to this. I believe they specify no more than 8 psi. If you are running a high flow mechanical pump, or something of that sort, you need to run a pressure regulator to meter it down.


Found this from the manual:
Do not use more than 6.5 PSI fuel pressure. Excessive fuel pressure may cause flooding. If your fuel pressure is too high, install an adjustable pressure regulator, such as Edelbrock #8190


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## ylwgto (Oct 27, 2009)

Well I'll be. this may be part of my woes as well. my fuel pressure gauge is boucing from 6-12psi at idle, so either a bad gauge or too much fuel pressure. could be causing a lot of my idle quality issues I'm having with my carb as well. ya learn something every day...


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## Baaad65 (Aug 29, 2019)

I have a Holley 110 gph and my gauge stays around 5-6 lbs and the pump has a pressure bypass I believe. 12lbs would be pretty high for a stock or even an aftermarket pump...something may be up.


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## geeteeohguy (Feb 2, 2008)

ylwgto said:


> Well I'll be. this may be part of my woes as well. my fuel pressure gauge is boucing from 6-12psi at idle, so either a bad gauge or too much fuel pressure. could be causing a lot of my idle quality issues I'm having with my carb as well. ya learn something every day...


This is an increasingly common issue that never used to happen in the days of USA made pumps. I've seen it a lot with bolt-on replacement mechanical pumps. 8-12 or more psi which causes fuel to bleed past the needle and seat and load up the engine. You can either 'luck out' and get a good pump or be forced to run a regulator.


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## AZTempest (Jun 11, 2019)

Sounds like everyone is on the right track with fuel pressure. 

One thing, unless you get a good car guy you may never be happy with a setup. All the more reason for just tweeking your setup yourself. With that said if you keep your 1411 don't be worried about adjusting it yourself. They are a very simple carb to play with as well as plenty of on line help out there. I like to play with carbs and was running the 1411 on my 326 before I started messing with my Qjet. The 1411 really made my engine come alive. I'm basically a stock setup with headers and it was a noticeable difference. 

Jim


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## armyadarkness (Dec 7, 2020)

If you get jammed up, pm me and Ill give you my number


ylwgto said:


> Well I'll be. this may be part of my woes as well. my fuel pressure gauge is boucing from 6-12psi at idle, so either a bad gauge or too much fuel pressure. could be causing a lot of my idle quality issues I'm having with my carb as well. ya learn something every day...


It has come up so often, I just assumed that everybody knew you can't run in Edelbrock carb with more than 6 PSI


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## armyadarkness (Dec 7, 2020)

geeteeohguy said:


> This is an increasingly common issue that never used to happen in the days of USA made pumps. I've seen it a lot with bolt-on replacement mechanical pumps. 8-12 or more psi which causes fuel to bleed past the needle and seat and load up the engine. You can either 'luck out' and get a good pump or be forced to run a regulator.


Yes this is why a few of us run the Edelbrock fuel pumps because they don't require the regulator and they are very consistent


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## Jared (Apr 19, 2013)

armyadarkness said:


> Yes this is why a few of us run the Edelbrock fuel pumps because they don't require the regulator and they are very consistent


Disclaimer to this. It depends on which pump you use. The higher flow Eddy pump runs at 12 psi and needs to be metered down. I'm running their std pump on mine without any issue and my engine is pretty high strung.


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## kevin1727 (Aug 4, 2021)

Initial timing is 16 BTDC. 
With vacuum it is 21 BTDC.
Charts I'm finding say initial timing should be about 6 to 9.
Engine never pings when driving.




__





1965-75 Pontiac & Tempest Tune-up Specifications


1965-75 Pontiac & Tempest engine tune-upspecifications including timing, dwell angle, and Spark Plug Gap, and firing order.



www.tpocr.com


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## Jared (Apr 19, 2013)

kevin1727 said:


> Initial timing is 16 BTDC.
> With vacuum it is 21 BTDC.
> Charts I'm finding say initial timing should be about 6 to 9.
> Engine never pings when driving.
> ...


Sounds like you're running way advanced. Have you tried checking it at full advance with the vacuum disconnected? You can do this with a basic timing light even if your damper isn't marked for every degree. Measure around your damper to get the exact size. Divide the length by 360 then multiply it by 36 and put a thin line at that measurement. Run the engine up to over 3000 RPM and see how close the line is to 0 on the timing tab.

I have a rowdy cam in mine and run the base timing at ~13 deg advanced.


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## PontiacJim (Dec 29, 2012)

kevin1727 said:


> Initial timing is 16 BTDC.
> With vacuum it is 21 BTDC.
> Charts I'm finding say initial timing should be about 6 to 9.
> Engine never pings when driving.
> ...



Seems a little high @16 Initial without vacuum, but can work depending on the build. But, also depends on your RPM set for idle. As idle RPM moves up, the advance can begin to go up - which can also depend on the springs used with the distributor weights.

21 BTDC with the vacuum connect may also be valid. This can depend on engine vacuum, the vacuum can being used, RPM, and if you use a ported or manifold (direct) vacuum source.

Coolant temps can also be used as an indicator for your timing settings. Incorrect, and the engine typically runs hotter.

Basically, not enough info to determine if your settings are good or bad. You need to know engine vacuum and what your timing curve is to determine what you really have. Detonation is what you want to avoid so you don't damage the engine - sometimes you can clearly hear it and other times you won't due to things like loud exhaust.

Plenty of past posts on timing and timing curves if you do a search.


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## kevin1727 (Aug 4, 2021)

armyadarkness said:


> Yes this is why a few of us run the Edelbrock fuel pumps because they don't require the regulator and they are very consistent


I hope I don't have to buy a $175 fuel pump.


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## Duff (Jan 12, 2020)

kevin1727 said:


> I hope I don't have to buy a $175 fuel pump.


At least they're available again, I waited 4 months for an Edelbrock, it never showed, so ended up buying a used one. I wouldn't wait to long to buy one.


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## kevin1727 (Aug 4, 2021)

PontiacJim said:


> Seems a little high @16 Initial without vacuum, but can work depending on the build. But, also depends on your RPM set for idle. As idle RPM moves up, the advance can begin to go up - which can also depend on the springs used with the distributor weights.
> 
> 21 BTDC with the vacuum connect may also be valid. This can depend on engine vacuum, the vacuum can being used, RPM, and if you use a ported or manifold (direct) vacuum source.
> 
> ...


Idle is 900rpm. 

Is there an easy way to disable mechanical advance to check timing? 
If I reduce the rpm and the timing doesn't change, would that indicate that the mechanical advance weights are at zero point? Or is there always some mechanical advance if the engine is running?

Are there any concerns with timing being advanced beyond spec as long as there is no detonation? 
I seem to remember that I set the timing as high as it would go without detonation back in the 70's to get best gas mileage.


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## Mine'sa66 (Oct 30, 2019)

kevin1727 said:


> I hope I don't have to buy a $175 fuel pump.


If you're over 6psi you will lift the needles off the seats and dump fuel. You can buy a mechanical pressure regulator to put inline pretty inexpensively.


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## kevin1727 (Aug 4, 2021)

Mine'sa66 said:


> If you're over 6psi you will lift the needles off the seats and dump fuel. You can buy a mechanical pressure regulator to put inline pretty inexpensively.


Do you have a suggestion for one? I don't have a return line to the tank so it would have to be a deadhead style. Some of them also have max pressure inputs or they blow the diaphragms. Not all the specs are available online so it's difficult to know exactly what will work.


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## kevin1727 (Aug 4, 2021)

From the builder:
My carb has the smallest jets and rods from the Edelbrock kit.
It's a standard Pontiac fuel pump. The builder measured it at just over 5 psi. 
The vacuum was 8 so he used the 3psi spring.


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## RMTZ67 (Mar 12, 2011)

kevin1727 said:


> I hope I don't have to buy a $175 fuel pump.


Is your mechanical pump a Carter or something else?


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## Mine'sa66 (Oct 30, 2019)

kevin1727 said:


> Do you have a suggestion for one? I don't have a return line to the tank so it would have to be a deadhead style. Some of them also have max pressure inputs or they blow the diaphragms. Not all the specs are available online so it's difficult to know exactly what will work.


I was troubleshooting a buddy's 71 Monte Carlo a few weeks back. Same issue as you. Way too rich. His fuel pump was over 8psi. Advance auto was just up the street, walked in and grabbed what they had....




__





Advance Auto Parts - Down for Maintenance






shop.advanceautoparts.com




It's a cheapy and can't drop more than 3-4 psi, but it did the trick. Guy at the counter suggested a Holly one for about 30 bucks more, would have grabbed it, but they were out of stock. It really doesn't take much unless your pump is out of control like over 10psi


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## kevin1727 (Aug 4, 2021)

Mine'sa66 said:


> I was troubleshooting a buddy's 71 Monte Carlo a few weeks back. Same issue as you. Way too rich. His fuel pump was over 8psi. Advance auto was just up the street, walked in and grabbed what they had....
> 
> 
> 
> ...


I saw those but the reviews weren't great so I wasn't sure. I guess it's worth a shot to see if it makes a difference.


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## Baaad65 (Aug 29, 2019)

Fired mine up this morning and I was at 7 lbs, needle steady...I forgot to check it when I got home but it think it drops a little when hot.


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## kevin1727 (Aug 4, 2021)

RMTZ67 said:


> Is your mechanical pump a Carter or something else?


It has "AC" embossed on the sides and "40678" part number.
Looks like this one. The small nipple is capped off. I don't have a return line to the tank.








1969 69 1970 70 GRAND PRIX GP NOS 6417418 FUEL PUMP 400 428 AC DELCO 40678 GM SJ | eBay


Find many great new & used options and get the best deals for 1969 69 1970 70 GRAND PRIX GP NOS 6417418 FUEL PUMP 400 428 AC DELCO 40678 GM SJ at the best online prices at eBay! Free shipping for many products!



www.ebay.com


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## kevin1727 (Aug 4, 2021)

Baaad65 said:


> Fired mine up this morning and I was at 7 lbs, needle steady...I forgot to check it when I got home but it think it drops a little when hot.


I don't have a gauge but I'm guessing it would go up with rpms?


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## Baaad65 (Aug 29, 2019)

kevin1727 said:


> I don't have a gauge but I'm guessing it would go up with rpms?


It shouldn't, it's not like oil pressure.


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## Jared (Apr 19, 2013)

kevin1727 said:


> It has "AC" embossed on the sides and "40678" part number.
> Looks like this one. The small nipple is capped off. I don't have a return line to the tank.
> 
> 
> ...


A stock fuel pump should be fine for an Edelbrock carb. That's what was on my old engine and the Camaro I used to have. Zero issues with it flooding the carb.


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## RMTZ67 (Mar 12, 2011)

kevin1727 said:


> It has "AC" embossed on the sides and "40678" part number.
> Looks like this one. The small nipple is capped off. I don't have a return line to the tank.
> 
> 
> ...


May not be your problem but, the rubber in them may not last with todays gas.


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## PontiacJim (Dec 29, 2012)

kevin1727 said:


> Idle is 900rpm.
> 
> Is there an easy way to disable mechanical advance to check timing?
> If I reduce the rpm and the timing doesn't change, would that indicate that the mechanical advance weights are at zero point? Or is there always some mechanical advance if the engine is running?
> ...


You can advance timing beyond spec as each engine build is different. The factory spec is on the conservative side to prevent engine issues/warranty claims and is more generic to apply to all engines with different cars going to different regions of the country - so in mass production, one size fits all and you go from there.

I saw 8" Hg of vacuum? That's a big cam and why the 900 RPM idle to keep the engine smoother and help build a little more vacuum. With that, you definitely want to have a matching vacuum advance can that works with the lower 8" Hg of vacuum - which your aftermarket distributor may have?

You should not get much mechanical advance below 1,000 RPM's, just a degree or 2, unless you have really light springs so the total mechanical advance is all in at 2,500 RPM's or slightly less. That is where knowing what your timing curve is so you can set all your parameters with regards to timing. Personally I would go with 3,000 - 3,500 RPM's for Total mechanical advance - Balancer Timing + Distributor weights/springs.

DO NOT make several changes at once. Get your fuel issued sorted out first. Once fixed, then move on to the next issue or you will be chasing your own tail and may not get to the issue or spend long hours doing so.


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## kevin1727 (Aug 4, 2021)

PontiacJim said:


> ............ I saw 8" Hg of vacuum? That's a big cam and why the 900 RPM idle to keep the engine smoother and help build a little more vacuum. With that, you definitely want to have a matching vacuum advance can that works with the lower 8" Hg of vacuum - which your aftermarket distributor may have? ..........
> ........DO NOT make several changes at once. Get your fuel issued sorted out first. Once fixed, then move on to the next issue or you will be chasing your own tail and may not get to the issue or spend long hours doing so. .........


Thanks!
I don't know what is normal on vacuum. That's the number the builder gave me.
Yes, the distributor has a vacuum canister on it. I'm reading that there are adjustments for it, but not knowing the details I haven't messed with it.
I'm only working on the rich condition now. Later this week, I'll be adding a 10um fuel filter and a cheapo fuel pressure regulator to see if that helps. The builder didn't install a fuel filter but I'm reading that is really desirable on performance carburetors. Then maybe a different fuel pump or good pressure regulator if pressure is really an issue.


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## geeteeohguy (Feb 2, 2008)

kevin1727 said:


> Idle is 900rpm.
> 
> *Is there an easy way to disable mechanical advance to check timing? *
> If I reduce the rpm and the timing doesn't change, would that indicate that the mechanical advance weights are at zero point? Or is there always some mechanical advance if the engine is running?
> ...


The mechanical advance is never touched or disabled to check base timing. Unless your distributor is gummed up and the weights are stuck in the advanced position, or somebody has monkeyed with it, you will not have any mechanical advance at idle speed. Depending on spring rates, the mechanicals don't start putting in advance until about 1200-1500 rpm.
Also, be advised that cranking up the base timing 10 degrees over spec is not a cure-all for ho-hum performance. These engines as designed were spec'd under ten degrees base, most were spec'd at 6 BTDC, for a reason by the engineers who designed them. The more your base timing is advanced, the weaker your top end will be. It's all a compromise, and the factory specs are a good place to start. Some hobbyists seem to know more than the factory engineers, and develop their own specs and modifications, with mixed results. Driving and owning Pontiacs since the '70's, I've never had the cause to run 16 degrees initial. It's a great way to break the lands out of the pistons, though.


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## PontiacJim (Dec 29, 2012)

*Kevin*: I don't know what is normal on vacuum.

*PJ*: 18-22" Hg for a stock engine and less on a modified engine.

*geeteeohguy*: The more your base timing is advanced, the weaker your top end will be.

*PJ:* And why you want to know your timing curve and may need to *LIMIT* with a stop/bushing your total advance when dealing with a BIGGER than stock cam having low vacuum that requires more Initial advance.

*geeteeohguy*: These engines as designed were spec'd under ten degrees base, most were spec'd at 6 BTDC, for a reason by the engineers who designed them.

*PJ*: the same engineers also knew that when installing a larger cam with more overlap that you had to raise the base timing. Case in point, 1970 RA IV - 15 degrees BTDC! More advance also gets the car moving quicker.

The initial advance requirement for a modified engine is very much dependent on the duration of the cam fitted. Below is a table of advance requirements and expected idle speeds for a range of cam specifications. *ON NO ACCOUNT* use these settings _before the maximum advance _on the distributor has been correctly limited.

Cam duration **Advance **Idle speed expected
270**************10-12 ********600-800
280****************12-14*********900-1000
290****************14-16********1000-1100
300**************16-18********1100-1200
310+*************18-20********1100-1400
When establishing static advance the golden rule is never use less than 10; never use more than 20 degrees. The engine may well tolerate more than 20 degrees at idle, but the moment the throttle is opened and cylinder filling is improved it will ping/detonate heavily.
One problem often encountered when using more static advance than standard is that the engine may 'kick-back' when starting. Initial advance MUST be set at 1000RPM or lower with the vacuum advance disconnected so that the centrifugal advance has not yet started its operation.

*geeteeohguy*: Driving and owning Pontiacs since the '70's, I've never had the cause to run 16 degrees initial.

*PJ:* Because since the 1970's you never owned one with a larger than stock aftermarket race type cam.

*geeteeohguy:* Depending on spring rates, the mechanicals don't start putting in advance until about 1200-1500 rpm.

*PJ*: See the enclosed chart for the 1968 Distributors. Note the various advance degrees based on RPM - look at Model 1111272 and tell me it doesn't start advancing until 1200-1500 RPM's.


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## geeteeohguy (Feb 2, 2008)

Correction here: my '65 has a pretty stout single pattern Sig Erson HI Flo cam in it that's been there for the past 41 years. This car does like 10 degrees BTDC initial timing and runs tubing headers as well as a tripower. Idle vacuum is about 9 to 12 inches hg. Power is great down low all the way past 6,000 rpm as long as it has the octane it needs.


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## kevin1727 (Aug 4, 2021)

Lot of good information. Thanks!


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## armyadarkness (Dec 7, 2020)

kevin1727 said:


> From the builder:
> My carb has the smallest jets and rods from the Edelbrock kit.
> It's a standard Pontiac fuel pump. The builder measured it at just over 5 psi.
> The vacuum was 8 so he used the 3psi spring.


Having an Edelbrock carb that is too small for your application, with the smallest jets available installed in it, is just wrong on many fronts. And the fact that you're too rich with such an under-fuled setup, is another good clue that your pump is pushing fuel past the needles.

I also think there's some confusion in your builders statement:
"The vacuum was 8 so he used the 3psi spring"

That's an Edelbrock formula for choosing needle springs. 

The first issue is, needle springs have no affect on AFRs. They change the rate at which the needles come out of the seats, fast or slow, late or early.
The next issue is, 8hg of vacuum would be the most radical cam I've ever seen in this forum, and if Im not mistaken, you have a mild/ stock build? Either way, using a dragstrip-only cam with an Edelbrock 600, is like loading a Howitzer with a .22Lr.
Finally, it sounds like the builder is confusing fuel pump pressure with engine vacuum.
I think a regulator will solve your issues. Edelbrock specifies in all of their videos that it must be below 6.5 psi. Since they're only vacuum operated, with too high fuel pressure, It's possible to physically "stick" the needles in the seats, which would make it super rich.

I have a Holley regulator if you need one.

And as for that "expensive" Edelbrock fuel pump, consider the facts that by the time you buy a new cheap fuel ppump, regulator, and replumb your fuel setup, there might not be as much cost difference as you thought, and for a cleaner setup, with a better pump.

Nonetheless... you're under carbed.


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## kevin1727 (Aug 4, 2021)

armyadarkness said:


> Having an Edelbrock carb that is too small for your application, with the smallest jets available installed in it, is just wrong on many fronts. And the fact that you're too rich with such an under-fuled setup, is another good clue that your pump is pushing fuel past the needles.
> 
> I also think there's some confusion in your builders statement:
> "The vacuum was 8 so he used the 3psi spring"
> ...


Based on what everyone here is saying and what I've found elsewhere, I'm staying with the Edelbrock 750cfm. I am adding a 10um filter to the fuel line between the pump and the carburetor. It's an Earl's Performance bronze element filter. Haven't decided what to do about the pressure regulator yet. If a cheapo regulator solves my problems, I will probably go with the Edelbrock fuel pump. 

I'm going to ask for an assortment of jets from the builder. He doesn't want to be responsible for any problems if I'm messing with the engine though. What is your opinion on taking the carb apart and checking the floats? I'm fairly mechanically competent although it's been a long time since I've done much. 

This is the cam spec I got from my builder.


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## armyadarkness (Dec 7, 2020)

kevin1727 said:


> Based on what everyone here is saying and what I've found elsewhere, I'm staying with the Edelbrock 750cfm. I am adding a 10um filter to the fuel line between the pump and the carburetor. It's an Earl's Performance bronze element filter. Haven't decided what to do about the pressure regulator yet. If a cheapo regulator solves my problems, I will probably go with the Edelbrock fuel pump.
> 
> I'm going to ask for an assortment of jets from the builder. He doesn't want to be responsible for any problems if I'm messing with the engine though. What is your opinion on taking the carb apart and checking the floats? I'm fairly mechanically competent although it's been a long time since I've done much.
> 
> ...


Edelbrocks are super easy to take apart and work on. I pm'd you a week ago and offered my number to help if you got jammed up.


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## kevin1727 (Aug 4, 2021)

armyadarkness said:


> Edelbrocks are super easy to take apart and work on. I pm'd you a week ago and offered my number to help if you got jammed up.


Not so much jammed up as I am struggling with a lack of information about the engine and tools like a vacuum gage, fuel pressure gage, compression tester.


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## Jared (Apr 19, 2013)

You can take the top of the carb off to check the float measurements in ~5 minutes without removing it from the engine. Only special tool you need is a drill bit that's the right size to use as a measurement gauge (I forget the size, but should be on the Edelbrock website, or ask @armyadarkness). Just make sure you don't drop anything down into the engine while you're working. Depending on the vintage of you're carb, it could have regular screws or it could be torx.

Your cam is pretty mild for a 428 build. You should have way more than 8psi vacuum. I'm thinking Amy is right and the 8psi is probably your fuel pressure.

Edelbrock used to include this on a DVD in the box when you bought a carb from them.


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## kevin1727 (Aug 4, 2021)

Hell, this is like a boat. A hole into which you pour money. LOL
Ordered a vacuum/pressure gage for testing both vacuum and fuel pressure, a compression tester, and fuel pressure regulator.

There's a car show coming up Saturday. That would be my first car show. Sure would like the car to be running good and NOT smoking when I go.


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## kevin1727 (Aug 4, 2021)

Jared said:


>


Right off he says a 600cfm would be correct for up to 454 cubic inch. He says 750cfm is only for highly modified large engines.


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## kevin1727 (Aug 4, 2021)

While checking out the distributor, I removed the rotor and discovered that it had been installed 180 out of alignment, with the square peg of the rotor forced into the round hole of the rotor mount.

I installed the rotor correctly and moved all the spark plug wires around to match. The rotor contact is now pointing towards the glove box at TDC. After reading, I see the rotor contact should be pointing towards the washer pump as a "rule of thumb" but I'm not sure it's worth the effort to change it right now.

I find I am now questioning everything my "Pontiac expert" builder has done. He did not build the base engine, but he installed it and all the components.


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## armyadarkness (Dec 7, 2020)

kevin1727 said:


> Right off he says a 600cfm would be correct for up to 454 cubic inch. He says 750cfm is only for highly modified large engines.


That's completely inaccurate for a Pontiac. Trust us.


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## armyadarkness (Dec 7, 2020)

kevin1727 said:


> While checking out the distributor, I removed the rotor and discovered that it had been installed 180 out of alignment, with the square peg of the rotor forced into the round hole of the rotor mount.
> 
> I installed the rotor correctly and moved all the spark plug wires around to match. The rotor contact is now pointing towards the glove box at TDC. After reading, I see the rotor contact should be pointing towards the washer pump as a "rule of thumb" but I'm not sure it's worth the effort to change it right now.
> 
> I find I am now questioning everything my "Pontiac expert" builder has done. He did not build the base engine, but he installed it and all the components.


Just stay on the course and try not to let the incidentals pile up and clutter your mind. The determination process is fairly simple and quick, so just stay focused on the facts at hand.

After a week of banging your head against the wall, we talked for 5 min and it led you to discover an improperly installed ignition, which in conjunction with the "8hg of vacuum", is so far two things that builder clearly doesnt understand.

So now verify the actual vacuum.

After that, replace the inadequate plug wires, and then if it's still not running right, move on to the valves... However, I suspect that correcting the rotor and wires is going to solve the mystery... or improve it.

I have an 800fm Edelbrock on my car and as @BearGFR mentioned, you're not going to over-carb the car. AND... this is not a jetting issue.


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## kevin1727 (Aug 4, 2021)

armyadarkness said:


> After a week of banging your head against the wall, we talked for 5 min and it led you to discover an improperly installed ignition, which in conjunction with the "8hg of vacuum", is so far two things that builder clearly doesnt understand.


Thanks for all your help! 
I'm sure I'll be calling you again.


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## ponchonlefty (8 mo ago)

Jared said:


> You can take the top of the carb off to check the float measurements in ~5 minutes without removing it from the engine. Only special tool you need is a drill bit that's the right size to use as a measurement gauge (I forget the size, but should be on the Edelbrock website, or ask @armyadarkness). Just make sure you don't drop anything down into the engine while you're working. Depending on the vintage of you're carb, it could have regular screws or it could be torx.
> 
> Your cam is pretty mild for a 428 build. You should have way more than 8psi vacuum. I'm thinking Amy is right and the 8psi is probably your fuel pressure.
> 
> Edelbrock used to include this on a DVD in the box when you bought a carb from them.


7/16 drill bit.


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## ponchonlefty (8 mo ago)

ponchonlefty said:


> 7/16 drill bit.


if the floats are in spec. check the floats for leaks. they could be taking on fuel making the float heavy.


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## larutan (Jun 27, 2018)

Install a Edelbrock pro4 fuel injection system. I did. You can thank me later


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## IceBolt (Jul 28, 2020)

My stock 400ci is happy with electric pump, 6.5psi fuel pressure and Brawler 750CFM.....and Progression Ignition Distributor where you set timing from your smart phone  You'll still need a timing light to set initial timing at 10degreesBDC before using the App to set the rest. I'm with @kevin1727 - i'm terrible at changing springs and bushings without taking the distributor out of car. I'm still watching YouTube videos so one day i can rebuild my engine from scratch.....still dreaming.

Ignore me and follow the great tips on this thread.


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## leoonan (11 mo ago)

kevin1727 said:


> I'm now on the second carburetor on my car.
> Rebuilt 428 engine, TH400, long tube headers, 3.36 rear end.
> 
> The car runs like an old U-Haul truck and the exhaust pipes are loaded with black soot.
> ...





kevin1727 said:


> I'm now on the second carburetor on my car.
> Rebuilt 428 engine, TH400, long tube headers, 3.36 rear end.
> 
> The car runs like an old U-Haul truck and the exhaust pipes are loaded with black soot.
> ...


if you are getting black soot in the tail pipe, stumble taking off, bad fuel milage. the engine is getting too much fuel, too rich. if the engine has back fired at all, it will take out the power valve in the holley carb. even if it back fired only one time.
are you using ac plugs.
if you are using autolite spark plugs. 
pull them out and put them in the trash.
if the distributor has vacuum advance, make Shure it is working and it has the right amount of vacuum. make shure the hose is come off the right port of the intake manifold.
put a vacuum gage in line between the intake manifold and the vacuum advance. make Shure it is not leaking. 
make Shure the secondaries on the carburetor are not opening to soon.
with it idling, look down in the carburetor to see if the is fuel coming out above the throttle plate.
check for a vacuum leak on the intake manifold mounting gasket to the head. the intake manifold my need to be resurfaced.
check for a vaccum leak at the carburetor mounting gasket.


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## Laurence Egerton (Apr 25, 2020)

kevin1727 said:


> I'm now on the second carburetor on my car.
> Rebuilt 428 engine, TH400, long tube headers, 3.36 rear end.
> 
> The car runs like an old U-Haul truck and the exhaust pipes are loaded with black soot.
> ...



Time to check if the builder put the timing gears/chain in correctly. Dollars to donuts he missed the mark.


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## Pontiac#67 (Jun 15, 2021)

kevin1727 said:


> I'm now on the second carburetor on my car.
> Rebuilt 428 engine, TH400, long tube headers, 3.36 rear end.
> 
> The car runs like an old U-Haul truck and the exhaust pipes are loaded with black soot.
> ...


Well first off you are over fueling, go to Holley.com they have a formula so you can get the right cfm. Then start with the basics TDC #1 some new plugs, fuel pump psi 5 to 8 is good.And buy a new carb I prefer a Holley myself, or use there efi system very nice. I have the stealth Holley 4150 sniper self tuning. Check them out good luck


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## PontiacJim (Dec 29, 2012)

armyadarkness said:


> That's completely inaccurate for a Pontiac. Trust us.


Correct. The suggested carb CFM is based on a "safe" rating where most of your engine RPM will be for a typical street cruising mode. It does not take into account a modified engine that has bigger cams, higher flowing heads, better exhaust, etc..

They use a formula that is a generality, but when you have a vacuum secondary carb, just like the Q-jet, the engine only uses what it needs, and that is somewhat controlled by the vacuum secondary opening. Responsiveness is also a factor of the primary bore size, smaller develops a higher air/fuel velocity so the engine responds "right now" - think tri-power and how you run off the center carb and then kick open the outer carbs or the Q-jet with small primary bores and the big secondaries. If you slapped on a Holley 1050 carb, it may work once you can get into the upper RPM's, but at the lower RPM's the air/fuel mixture velocity would be sluggish and when you cracked it open, the engine might back fire through the carb or die. You can bandaide the problem by going way bigger on the accelerator pump squirt, but it still might not b enough. 

So this is one thing to consider as well and it can be a good idea to see what the manufacturer provides for the primary and secondary bore sizes. Here is an example and you can see how the bore diameters change to get the advertised CFM ratings of each carb:
Edelbrock 500CFM AVS2 - Primary 1.44" Dia Secondary 1.6875" Dia..
Edelbrock 650CFM AVS2 - Primary 1.44" Dia Secondary 1.75" Dia..
Edelbrock 800CFM AVS2 - Primary 1.75" Dia Secondary 1.75" Dia..

The 750 Q-jet has 1 3/8" (1.375") Diameter Primaries and 2 1/4" (2.25") Diameter Secondaries - so great air/fuel velocity from the smaller primaries and all that extra air flow as the vacuum secondaries pop open.

So when the tech guy suggests a 650CFM, ask him how it is that the factory used a 750CFM carb and the 396/454 Chevy engines used a Holley 780 CFM carb.


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## kevin1727 (Aug 4, 2021)

Laurence Egerton said:


> Time to check if the builder put the timing gears/chain in correctly. Dollars to donuts he missed the mark.


That's a huge amount of work, right? I was trying to see if there was a simpler way to check without tearing down so much and hoping it all goes back together without oil leaks.
I am suspecting something else wrong since two different carburetors don't work. I'm just hoping it's something I can fix easily, so I'm looking at the simple possibilities first.


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## kevin1727 (Aug 4, 2021)

Pontiac#67 said:


> Well first off you are over fueling, go to Holley.com they have a formula so you can get the right cfm. Then start with the basics TDC #1 some new plugs, fuel pump psi 5 to 8 is good.And buy a new carb I prefer a Holley myself, or use there efi system very nice. I have the stealth Holley 4150 sniper self tuning. Check them out good luck


EFI means new fuel tank, lines, fuel pump, computer module, etc. Not ready to dump a lot of money into this thing.


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## armyadarkness (Dec 7, 2020)

kevin1727 said:


> That's a huge amount of work, right? I was trying to see if there was a simpler way to check without tearing down so much and hoping it all goes back together without oil leaks.
> I am suspecting something else wrong since two different carburetors don't work. I'm just hoping it's something I can fix easily, so I'm looking at the simple possibilities first.


Lets not perform open heart surgery until we see if the Rolaids works


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## armyadarkness (Dec 7, 2020)

kevin1727 said:


> EFI means new fuel tank, lines, fuel pump, computer module, etc. Not ready to dump a lot of money into this thing.


There's no need to. These cars became world-famous, $120,000 collectibles, with Rochesters on them. Yes, efi and overdrive are sweet upgrades, but there's a lot more to it than just purchasing parts.

In the 50's and 60's; 200lb vacuum tube stereos were all the rage. In the 90's and 2000's, 5lb, class D, portable bluetooth stuff accounts for 98% of the market, yet all the experts still use tubes.

I still wind my watch.


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## kevin1727 (Aug 4, 2021)

I took the carburetor apart this morning. I'm kind of a clean freak because I worked around lasers, optics, and sensitive electronics so maybe I'm off base; but I thought the carburetor had excessive dirt in it. Sediment was clearly visible in the bowls but stirred into a cloud with the gasoline when disturbed. I cleaned everything, checked the metering rods, orifices, and float valves. I didn't see anything that I think could clog an orifice.

The floats were off. One was quite a bit off and about an 1/8" below the 7/16". I spent a long time adjusting and rechecking them and I'm satisfied that they meet the setting specs now.

The base gasket looked good. All the surfaces of the carb and manifold were flat and smooth. No signs of any vacuum leak around it.

Waiting for the filter and regulator to arrive later today. I'll install tomorrow morning and start it up then.


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## geeteeohguy (Feb 2, 2008)

kevin1727 said:


> That's a huge amount of work, right? I was trying to see if there was a simpler way to check without tearing down so much and hoping it all goes back together without oil leaks.
> I am suspecting something else wrong since two different carburetors don't work. I'm just hoping it's something I can fix easily, so I'm looking at the simple possibilities first.


You need to verify basic cam timing and distributor timing. This can be done without extensive teardown. I would see if the balancer is at 0 TDC when the #1 plug puffs compression out of the spark plug hole. If it does, likely the chain is set up right. Next thing to check is the distributor rotor position. It should be pointing at #1 on the cap when the piston is at TDC. Pontiacs rotate opposite Chevies.


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## geeteeohguy (Feb 2, 2008)

Kevin, put a vacuum guage on it. That will tell you a LOT. You may be chasing ghosts due to basic assembly mistakes of the engine/accessories.


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## kevin1727 (Aug 4, 2021)

geeteeohguy said:


> Kevin, put a vacuum guage on it. That will tell you a LOT. You may be chasing ghosts due to basic assembly mistakes of the engine/accessories.


I will.

My test equipment is due tomorrow. I live in the boonies so I order most stuff online. Saves driving to two or three small towns to locate parts.


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## armyadarkness (Dec 7, 2020)

geeteeohguy said:


> Kevin, put a vacuum guage on it. That will tell you a LOT. You may be chasing ghosts due to basic assembly mistakes of the engine/accessories.


I told him on Tuesday to hold off on any major work until he got one. He has one on order!


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## kevin1727 (Aug 4, 2021)

geeteeohguy said:


> .....
> Next thing to check is the distributor rotor position. It should be pointing at #1 on the cap when the piston is at TDC. Pontiacs rotate opposite Chevies.


From what I understand with cylinder #1 at compression stroke TDC, the distributor can be inserted at any angle and the #1 plug attached at the distributor to match the rotor position and the rest following rotation order.

Is that correct?

That's how mine is set up.


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## armyadarkness (Dec 7, 2020)

kevin1727 said:


> From what I understand this is a rule of thumb and not a mechanical requirement. With cylinder #1 at compression stroke TDC, the distributor can be inserted at any angle and the plug wires attached at the distributor to match the rotor position and rotation.
> 
> Is that correct?


At the risk of blowing peoples minds, yes.


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## kevin1727 (Aug 4, 2021)

geeteeohguy said:


> You need to verify basic cam timing and distributor timing. This can be done without extensive teardown. I would see if the balancer is at 0 TDC when the #1 plug puffs compression out of the spark plug hole. If it does, likely the chain is set up right. ....


I might try this. I have access to a dial indicator and I have my cam spec.




__





How to find cam timing with motor assembled







www.crankshaftcoalition.com


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## kevin1727 (Aug 4, 2021)

This is the gage I bought. Can test both vacuum and fuel pressure.


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## armyadarkness (Dec 7, 2020)

When I first got my car, the ignition had been severely neglected.

So, I pulled the cap and recorded the position of the rotor and vac can, pulled the dizzy and swapped it with an HEI, as Ive done MANY MANY times before, and put it back together. The car wouldnt run.

It took days and weeks to sort it all out.

Then a few years later, just recently, when pulling my new dizzy to swap out the timing bushings, I again marked it all and recorded everything. The same thing happened!!!

As it turns out, my oil pump spun on its own when the dizzy was out of the engine!!!! Which threw things off on re-installation... So the moral of the story is, NEVER let the oil pump or vac can dictate where the rotor is pointing. Point the rotor at the number one wire when the engine #1 is on TDC, and it'll start.


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## Sick467 (Oct 29, 2019)

kevin1727 said:


> From what I understand with cylinder #1 at compression stroke TDC, the distributor can be inserted at any angle and the #1 plug attached at the distributor to match the rotor position and the rest following rotation order.
> 
> Is that correct?
> 
> That's how mine is set up.





armyadarkness said:


> At the risk of blowing peoples minds, yes.


I agree that your statement is correct, but I'm getting to forgetful to remember when I need to and just do things like that by the book. Surely at some point down the road I'd pull the cap wires and put them back per the book, not remembering that I clocked them differently, all the time swearing that the wires fit nicely before pulling them! That's how my mind would be blown! lol


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## kevin1727 (Aug 4, 2021)

Sick467 said:


> I agree that your statement is correct, but I'm getting to forgetful to remember when I need to and just do things like that by the book. Surely at some point down the road I'd pull the cap wires and put them back per the book, not remembering that I clocked them differently, all the time swearing that the wires fit nicely before pulling them! That's how my mind would be blown! lol


Fortunately I haven't cut and installed my new set of cut-to-length wires yet. Once I get everything set, I'll put those on and I'll have a reference I can use.


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## geeteeohguy (Feb 2, 2008)

armyadarkness said:


> When I first got my car, the ignition had been severely neglected.
> 
> So, I pulled the cap and recorded the position of the rotor and vac can, pulled the dizzy and swapped it with an HEI, as Ive done MANY MANY times before, and put it back together. The car wouldnt run.
> 
> ...


I always mark the position of the rotor tab to a part on the engine before I lift out the distributor. When putting it back in, if it won't 'click down' into place that last quarter inch to return to the same exact position, I take a long slot screwdriver and turn the oil pump shaft slightly. The rotor tab on re-installation MUST be exactly where it was prior to pulling the distributor out of the block. Before going any further, I recommend eliminating the obvious issues (distributor position). Get the dizzy back to the factory location, get the firing order back to factory on the cap, and go from there. At least you will know that you won't have issues in that area.


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## kevin1727 (Aug 4, 2021)

Fuel filter and regulator installed. Tested vacuum at location in place of distributor line. It is "not" the timed port.








vacuum1







www.youtube.com





According to the video linked above about vacuum testing, it is worn valve guides. It's a newly rebuilt engine with new valve guides though.


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## kevin1727 (Aug 4, 2021)

At higher RPM.








vacuum2







youtube.com


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## kevin1727 (Aug 4, 2021)

Drove the car about a half hour. There is no improvement in the way the engine runs or the smoking. 
I'm trying to see if the builder will take the car back and sell it for me.


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## armyadarkness (Dec 7, 2020)

That's just ridiculous. I would be checking to see if the valves were adjusted properly.


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## armyadarkness (Dec 7, 2020)

And didn't this guy just build the motor? So if something's wrong it's something he did, no?


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## kevin1727 (Aug 4, 2021)

armyadarkness said:


> And didn't this guy just build the motor? So if something's wrong it's something he did, no?


His answer is that the carb is too big and needs a new 600cfm. He says some smoking is normal on these big high performance engines.


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## kevin1727 (Aug 4, 2021)

armyadarkness said:


> That's just ridiculous. I would be checking to see if the valves were adjusted properly.


I have no knowledge to do that. I'm just tired of dealing with it. I don't think it's the carb either. I think there is something else wrong. I've already passed my limit on dumping money into the car, upgrades, and tools. It's a really nice car but I can't afford it.


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## sameold01 (Jun 21, 2020)

You have a valve adjustment and or cam timing issue. My crower 60243 @50 228, 234 280, 290 I have 17" vacuum at idle. With your initial at 16 you should be closer to 18" at idle.
Step away from the car for a little bit maybe a week. This kind of stuff will drive you crazy.


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## Sick467 (Oct 29, 2019)

kevin1727 said:


> His answer is that the carb is too big and needs a new 600cfm. He says some smoking is normal on these big high performance engines.


Smoking from these engines is NOT normal. I have a mild 400 in a recent build and does not smoke a lick. My old 40,ooo mile 400 HP 400 didn't visibly smoke either...used some oil, but that IS normal in my experience.



kevin1727 said:


> I have no knowledge to do that. I'm just tired of dealing with it. I don't think it's the carb either. I think there is something else wrong. I've already passed my limit on dumping money into the car, upgrades, and tools. It's a really nice car but I can't afford it.


It sounds like it's time to set it aside and take a break. It also sounds like your builder is scrambling to make you go away. I don't know who you are dealing with and I don't mean them any disrespect, but I have dealt with folks that talk a big talk up front, supply a whisper [email protected], and then talk big again when it looks like it will get into their shorts. The advice you have been getting here has been very solid. I'd challenger your builder to come up with a loaner carb to prove his statements. Heck, if I had one, I'd send it to you.

It won't work, but at least it will put them in their place.

Valve adjustment don't take any special tools...just some you tube time and some help from the good folks here.

If I thought I could afford another classic...a 64 Pontiac would be IT. Take a breather and come back to it after you have stained the deck, fixed the roof, installed the pool you always wanted or whatever. A smoking car does not bring much due to the unknowns and if you fix it...you won't want to sell it.


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## Baaad65 (Aug 29, 2019)

I can't believe you want to sell that nice car after all the time work and money just because it needs some tuning. Is there another shop you can have it looked at and maybe determine if the idiot who did the motor messed something up? If he did he should fix it for free, he says the carb is to big but yet wants to order another one the same size? And it's not to big as many here have pointed out, you actually could use a bigger one like a 750cfm, it might need to be tuned or rebuilt if not new and who's paying for the new carb? And he's also wrong that big performance motors smoke, mine doesn't. Find another shop and don't let that hack touch your car before giving up, its to nice of a car. These cars are almost 60 years old and take a lot of up keep and tools but that's the hobby we chose to love...but sometimes it is maddening. Keep the faith brother ✊


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## armyadarkness (Dec 7, 2020)

kevin1727 said:


> His answer is that the carb is too big and needs a new 600cfm. He says some smoking is normal on these big high performance engines.


I have to say, this guy may be clinically insane. I have a mild 400 and Edelebrock recommended an 800 cfm carb. Thats what it was dyno'd with.

In stock form, from the factory, your car had a 750 cfm carb on it, so how now that its modified, is it being over fueled by a vacuum secondary 600? And didnt you just buy a new 750?

AFAIC, yo u need to document all of this, cut ties with this guy, and bring your car to be tuned by a tuner. Surely there must be a dyno or hot rod shop near by?


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## armyadarkness (Dec 7, 2020)

kevin1727 said:


> I have no knowledge to do that. I'm just tired of dealing with it. I don't think it's the carb either. I think there is something else wrong. I've already passed my limit on dumping money into the car, upgrades, and tools. It's a really nice car but I can't afford it.


It's an irreplaceable car that you have a tremendous investment in. It shouldnt need any more parts... it needs to be tuned! South Carolina must have hundreds of speed shops. And if you cant afford that, take a deep breath and we'll walk you through it.

Is the fuel regulator on yet?

What heads are on this thing? Do they have screw in studs? 

Its easy to adjust valves.


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## sameold01 (Jun 21, 2020)

These older pontiac engines even up to 1969 don't you torque the rockers to 20 foot lbs if the valvetrain is all stock?


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## armyadarkness (Dec 7, 2020)

sameold01 said:


> These older pontiac engines even up to 1969 don't you torque the rockers to 20 foot lbs if the valvetrain is all stock?


Im not the most qualified to asnwer that, but yes, to my knowledge thats true. 

One thing is clear, his new engine either has a hanging valve or too much fuel pressure.


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## kevin1727 (Aug 4, 2021)

Here's a photo of the plugs when I removed them after one hour of driving at mostly highway speed right after the 750 Edelbrock was installed. #1 and #6 are clean but the rest are dirty. Yes, #1 has a tiny chip or mold imperfection on the center insulator. If it is a carburetor problem why aren't all the plugs the same? Seems more like a valve or ring issue to me.


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## Jared (Apr 19, 2013)

kevin1727 said:


> His answer is that the carb is too big and needs a new 600cfm. He says some smoking is normal on these big high performance engines.


This is an unacceptable answer. My 461 is putting out somewhere around 500hp and it doesn't smoke.


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## kevin1727 (Aug 4, 2021)

What about the YouTube video on vacuum diagnosis with the vacuum gauge vibrating? My builder said that is normal opening and closing of the valves. The video online said it is leaking valve guide seals. Research online says leaking valve guide seals cause smoke on startup, at idle, and when starting off after idle. My car has those symptoms. 
Maybe a can of 


Advance Auto Parts - Down for Maintenance


I haven't found a speed shop willing to work on it. They're all looking for help and don't have the time. 
If anyone knows someone in upstate SC, I would be willing to give it a try but I'm sort of broke right now because of other issues. I don't want the builder messing with it.


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## kevin1727 (Aug 4, 2021)

I installed a 10um sintered metal fuel filter and the Mr Gasket fuel pressure regulator set to 4-1/2 psi. No change in performance or smoking.


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## Jared (Apr 19, 2013)

To me #1 and #6 don't look like they're firing at all. Hard to tell from a picture but they look too clean to me. I'm leaning towards the valve adjustment idea. Something is really wrong here. If it was a carb issue, all the plugs would look the same.


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## Sick467 (Oct 29, 2019)

sameold01 said:


> These older pontiac engines even up to 1969 don't you torque the rockers to 20 foot lbs if the valvetrain is all stock?


Yes, the stock hydraulic lifter V8 engines would have the rocker nuts torqued to 20ft-lb. My Motor's manual covers '67 to '73 and all the hydraulic lifter V8's are set the same as you mention...










However, I have had limited experience with the used original nuts backing off slightly (causing some clickity-clacking) and the two 400's that I have built got locking nuts. I set the valves with the motor running or by setting them on the stand with the valve on the low side of the cam and the "feel" method on pushrod twist resistance. Doing it with the motor running is easiest, and the messiest. The other method takes more time and a fair amount of turning the engine over by hand. IIRC, there are valve sequences that allow you to set the valves with minimal amounts of engine rotation. Either way, it's not hard.


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## kevin1727 (Aug 4, 2021)

Does anyone else see vacuum oscillations like I'm seeing at idle? The engine actually sounds okay to me. Maybe a little rough at idle? My V8 experience is limited to factory 305 and 350 Chevys with smooth, quiet idle. 








vacuum1







youtube.com


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## Baaad65 (Aug 29, 2019)

I think Jared is onto something those two plugs look way to clean like they're not firing but then again in the video it does sound good, if two cylinders weren't firing you'd see the motor shaking bad. Make sure you have spark to those cylinders. And if you had fuel pressure issues and the carb was out of adjustment of course the plugs will look bad. One more thing, can you determine if the smoke is black or blue? Black is to much fuel blue is oil, but black sooty tail pipes are normal.


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## sameold01 (Jun 21, 2020)

What kind of ignition set up do you have on this motor? points, hei?


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## Sick467 (Oct 29, 2019)

kevin1727 said:


> Does anyone else see vacuum oscillations like I'm seeing at idle? The engine actually sounds okay to me. Maybe a little rough at idle? My V8 experience is limited to factory 305 and 350 Chevys with smooth, quiet idle.
> 
> 
> 
> ...


1 - 1.5 in Hg vibration would be normal for my [email protected] 289/331, my mild Pontiac 400, and my moderately cheap gage. However, my builds have a few more inches of vacuum at idle. My cams are not very radical...The 289 is a street strip cam and the other is more of a RV cam.


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## kevin1727 (Aug 4, 2021)

Baaad65 said:


> I think Jared is onto something those two plugs look way to clean like they're not firing but then again in the video it does sound good, if two cylinders weren't firing you'd see the motor shaking bad. Make sure you have spark to those cylinders. And if you had fuel pressure issues and the carb was out of adjustment of course the plugs will look bad. One more thing, can you determine if the smoke is black or blue? Black is to much fuel blue is oil, but black sooty tail pipes are normal.


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## kevin1727 (Aug 4, 2021)

Sick467 said:


> 1 - 1.5 in Hg vibration would be normal for my [email protected] 289/331, my mild Pontiac 400, and my moderately cheap gage. However, my builds have a few more inches of vacuum at idle. My cams are not very radical...The 289 is a street strip cam and the other is more of a RV cam.


Is your vacuum gauge rapidly oscillating like mine? I'm getting 1.5 vibration range.


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## kevin1727 (Aug 4, 2021)

sameold01 said:


> What kind of ignition set up do you have on this motor? points, hei?


HEI, no points.


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## Sick467 (Oct 29, 2019)

kevin1727 said:


> Is your vacuum gauge rapidly oscillating like mine? I'm getting 1.5 vibration range.


It bounces like yours, jumping 1 to, maybe, 2 inches of Hg. I just split the difference for my reading. That is with my handheld, no-name, gage. I have a AutoMeter gage mounted in the dash for my 400 engine and it only bounces about a 1/4" Hg once warmed up (at about 14" Hg). The handheld gage will bounce on that engine, however. I have a cheap handheld gage, I guess.


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## Baaad65 (Aug 29, 2019)

kevin1727 said:


>


Maybe blue but hard to tell, how does it smell? Has the level dropped on the dipstick that you can tell? Did the builder break the motor in or did you, do we think the rings are seated, how many miles on the motor now???


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## Mine'sa66 (Oct 30, 2019)

kevin1727 said:


>


That looks more like oil smoke than fuel smoke. Add that to your vacuum gauge readings and your spark plug condition and I'd surmise you have some valve train issues.


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## Jared (Apr 19, 2013)

Speaking of engine oil, you may want to give yours a sniff test. Make sure you're not dumping raw fuel into the crank case.


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## sameold01 (Jun 21, 2020)

If we can figure out if your valvetrain is adjustable or torque the rockers to 20lb. I presume you have an adjustable valvetrain setup being your being your lift is over .450. with the cam your using. I have an easy way of adjusting valves that you can do in a couple hours by yourself with our help. Maybe pop a valve cover off so we can see if your willing to do that .


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## Jared (Apr 19, 2013)

This has been a long thread and we haven't gotten to the bottom of it yet. I looked back through and don't think it's been asked yet. Based on your build, I'm assuming your engine should be somewhere in the low 400hp range. You said you've driven it. Does it feel like it has the power it should? I broke in my engine with a 600cfrm carb, and even with the too small carb, the car was extremally fast.

I'm with @sameold01 If it were mine I'd want to pull the valve covers and see what's going on in there. Make sure all the rockers are moving like they should.


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## Baaad65 (Aug 29, 2019)

Do you have the build sheet showing all the parts used, bearing clearances, ring gaps as installed, what was done to the heads??? Maybe it was in an earlier thread idk. You could run a compression and leak down test easy enough with a rented tester, Oriellys takes a deposit then returns it so its a free rental. Also do you trust this builder that he did what he said he did with the motor, is he experienced with Pontiacs, did you research him?


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## kevin1727 (Aug 4, 2021)

Jared said:


> This has been a long thread and we haven't gotten to the bottom of it yet. I looked back through and don't think it's been asked yet. Based on your build, I'm assuming your engine should be somewhere in the low 400hp range. You said you've driven it. Does it feel like it has the power it should? I broke in my engine with a 600cfrm carb, and even with the too small carb, the car was extremally fast.
> 
> I'm with @sameold01 If it were mine I'd want to pull the valve covers and see what's going on in there. Make sure all the rockers are moving like they should.


I think the car is a dog for the engine size. It will NOT spin the tires. I haven't timed it but I'm certain my 2017 F-150 5 litre would outrun it.


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## kevin1727 (Aug 4, 2021)

I thought I noticed this noise the other day but wasn't sure. I thought it might be my fuel pressure regulator bouncing around on the valve cover so I made sure that wasn't it.
I drove the car a few miles today to get it warmed up well. Can you hear this intermittent tap/knock noise after I got back home?









Intermittent knock at idle?


Sounds like something tapping on the valve cover.




youtube.com


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## sameold01 (Jun 21, 2020)

Pull a valve cover and check whats going on . If you have adjustable valves I think they are too tight. I have a over .500 just a bit .502 on mine and I'm using the ram air valve cover gaskets 1/4 thick for rocker clearance. Check your oil does it smell like gas and I'm sure you know you need the hot rod zinc oil 10w40 and good filter WIX. If smell like gas drain your oil warm and lets take a look at valve adjustment.


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## Jared (Apr 19, 2013)

Idle is really rough for the cam profile you have in there. I'm thinking you may be down a couple cylinders. Best case is this is due to rocker adjustment or a bad vacuum leak (intake manifold or something like that). You can check for vacuum leaks pretty easy with a stethoscope or a length of vacuum line stuck in your ear (This does work, I've done it). Do you know how the cam was broken in? It is very possible to wipe one out if broken in improperly (or not broken in at all and allowed to sit at idle).


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## kevin1727 (Aug 4, 2021)

FYI - just trying stuff. 
I disconnected the PCV hose and plugged it. The vacuum gage is now steady and not vibrating at 12.


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## kevin1727 (Aug 4, 2021)

Jared said:


> Idle is really rough for the cam profile you have in there. I'm thinking you may be down a couple cylinders. Best case is this is due to rocker adjustment or a bad vacuum leak (intake manifold or something like that). You can check for vacuum leaks pretty easy with a stethoscope or a length of vacuum line stuck in your ear (This does work, I've done it). Do you know how the cam was broken in? It is very possible to wipe one out if broken in improperly (or not broken in at all and allowed to sit at idle).


I checked for vacuum leaks using starter fluid around the base of the carb and at the intake manifold to head points. I even plugged all the vacuum inlets on the carburetor. No change except I discovered that the gage oscillations go away when the PCV is not connected. 
The cam was broken in.


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## sameold01 (Jun 21, 2020)

No oil leaks at all? Is there a gasket or sealer on your valley pan for the lifters?


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## kevin1727 (Aug 4, 2021)

sameold01 said:


> No oil leaks at all? Is there a gasket or sealer on your valley pan for the lifters?


Zero oil leaks. Yes, I can see there is a gasket or sealant.


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## Baaad65 (Aug 29, 2019)

I wouldn't run it anymore until you pull the covers, sounds like a loose rocker as its intermittent and if comes off and apart you will want to sell the car.


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## Jared (Apr 19, 2013)

If I hadn't seen your plugs I'd be recommending that you check timing. While I think you may need to do that too, the plugs tell that you have something strange going on with at least two cylinders. Looking at the rockers will give you a ton of insight into possible issues. With both valve covers off, look to make sure that all the rockers are still where they belong. Turn the engine over and make sure they are all going up and down as they should. Either way, readjust the rockers. I did it slightly different than the video @sameold01 posted, but that method should work. Only difference is Comp recommends a half turn past zero lash for preload instead of the 3/4 the guy in the video used.


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## Jared (Apr 19, 2013)

Here's a video of a guy doing a Pontiac engine:


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## Sick467 (Oct 29, 2019)

I had a rocker slip off to the side of a pushrod/valve once. It sounded sporadic and tinny like your noise. Pop the valve covers before running it any more.


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## Mine'sa66 (Oct 30, 2019)

kevin1727 said:


> I checked for vacuum leaks using *starter fluid *around the base of the carb and at the intake manifold to head points. I even plugged all the vacuum inlets on the carburetor. No change except I discovered that the gage oscillations go away when the PCV is not connected.
> The cam was broken in.


Holy cow, do you mean carb cleaner?
Please DO NOT use starting fluid to look for vacuum leaks!!!


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## Mine'sa66 (Oct 30, 2019)

kevin1727 said:


> I thought I noticed this noise the other day but wasn't sure. I thought it might be my fuel pressure regulator bouncing around on the valve cover so I made sure that wasn't it.
> I drove the car a few miles today to get it warmed up well. Can you hear this intermittent tap/knock noise after I got back home?
> 
> 
> ...


Pull a valve cover and look, something is wrong


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## ponchonlefty (8 mo ago)

kevin1727 said:


> His answer is that the carb is too big and needs a new 600cfm. He says some smoking is normal on these big high performance engines.


um,no that's not accurate.he probably did not rebuild the heads properly.the guides are probably worn and need replaced. or machined incorrectly.


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## ponchonlefty (8 mo ago)

sameold01 said:


> These older pontiac engines even up to 1969 don't you torque the rockers to 20 foot lbs if the valvetrain is all stock?


yes.


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## kevin1727 (Aug 4, 2021)

In order to take that valve cover off, I'll need to remove the power brake booster. It's in the way.
How much trouble is that?


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## Baaad65 (Aug 29, 2019)

kevin1727 said:


> In order to take that valve cover off, I'll need to remove the power brake booster. It's in the way.
> How much trouble is that?


There's no way to jenga it out? I think the brake lines have to be taken off the master, unbolt from the firewall and maybe you can move it over enough but you'll have to blead the brakes and be careful brake fluid makes a great paint stripper. Then do yourself a favor and get an 8 or 9 inch dual booster and you won't have this problem again especially when you buy my old valve covers after I get the new ones 😄 I saw that coming and have an 8" dual booster and the brakes are great on mine.


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## Baaad65 (Aug 29, 2019)

....thinking some more maybe the brake lines would flex enough if you're really close to getting the cover off by unbolting the whole brake assembly from the firewall but be careful not to kink a line.


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## Jared (Apr 19, 2013)

I had to look close at your video to see how close the booster is to the valve cover. I'm thinking @Baaad65 s recommendation of just unbolting it and moving it aside should make enough room to sneak it out. Pull the other side first. Figure you had a clean plug on that side too.


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## RMTZ67 (Mar 12, 2011)

kevin1727 said:


> Here's a photo of the plugs when I removed them after one hour of driving at mostly highway speed right after the 750 Edelbrock was installed. #1 and #6 are clean but the rest are dirty. Yes, #1 has a tiny chip or mold imperfection on the center insulator. If it is a carburetor problem why aren't all the plugs the same? Seems more like a valve or ring issue to me.
> 
> View attachment 157287


Did you clean them before this run? Those two look awfully clean to me. Are you sure its smoke and not steam? Is the smoke white or black? Or did I miss that conversation?
For now, take the valve cover off the easy side , put some cardboard so oil wont drip all over and make us a video. Hopefully the cam is not bad. Who broke it in?


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## Baaad65 (Aug 29, 2019)

RMTZ67 said:


> Did you clean them before this run? Those two look awfully clean to me. Are you sure its smoke and not steam? Is the smoke white or black? Or did I miss that conversation?


Welcome to the party RM, ya that was 16 pages back 🤣 I'm just kidding you know and having some cheap wine, can't afford good stuff after the parts I've been buying 😉


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## armyadarkness (Dec 7, 2020)

It looks like the one plug isnt even firing... remember when your rotor was on cocked, that's what I suspected would happen. Has it been replaced?


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## armyadarkness (Dec 7, 2020)

kevin1727 said:


> What about the YouTube video on vacuum diagnosis with the vacuum gauge vibrating? My builder said that is normal opening and closing of the valves. The video online said it is leaking valve guide seals. Research online says leaking valve guide seals cause smoke on startup, at idle, and when starting off after idle. My car has those symptoms.
> Maybe a can of
> 
> 
> ...


Give me a call again tomorrow and lets get this sorted. I think its just a simple rocker arm


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## RMTZ67 (Mar 12, 2011)

Baaad65 said:


> Welcome to the party RM, ya that was 16 pages back 🤣 I'm just kidding you know and having some cheap wine, can't afford good stuff after the parts I've been buying 😉


I stopped reading prior and when I jump back on I seen the pic of the plugs lol. I will say that when I broke in my Camaro, I could not get it running right and had no balls. Come to find out cam was gone...so I agree with remove the valve covers and lets have a look. I'll try to keep up with the class next time.


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## Baaad65 (Aug 29, 2019)

armyadarkness said:


> Give me a call again tomorrow and lets get this sorted. I think its just a simple rocker arm


on cocked, ? Is that what she said or he said 🤔


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## kevin1727 (Aug 4, 2021)

armyadarkness said:


> Give me a call again tomorrow and lets get this sorted. I think its just a simple rocker arm


I was able to get the valve cover off without removing the brake booster.
Y'all guessed it right. Comments about the clean plugs were spot on too. 
Here's #1 cylinder:









Here's #6 cylinder:









A couple other rockers are like this:


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## Baaad65 (Aug 29, 2019)

Ya but is that with valve fully closed? The experts can weigh in but maybe the rich condition was caused by the motor not using all the fuel?


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## RMTZ67 (Mar 12, 2011)

Pull out the push rod on the one to see that its still in good shape.


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## kevin1727 (Aug 4, 2021)

RMTZ67 said:


> Pull out the push rod on the one to see that its still in good shape.


They're chewed up on the ends. But they are straight.


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## kevin1727 (Aug 4, 2021)

Pulled the plugs and looked at them. Except for #1 and #6 being wet with oil, all the other ones look much better after I added the fuel filter and regulator.


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## kevin1727 (Aug 4, 2021)

Baaad65 said:


> Ya but is that with valve fully closed? The experts can weigh in but maybe the rich condition was caused by the motor not using all the fuel?


The builder is still blaming the carburetor. He says the rich condition fouled the plugs, causing detonation which damaged the push rods. But the plugs are not fouled now.


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## RMTZ67 (Mar 12, 2011)

kevin1727 said:


> The builder is still blaming the carburetor. He says the rich condition fouled the plugs, causing detonation which damaged the push rods. But the plugs are not fouled now.


I would like to know if the lifters and cam are still good. Was it running like this from the get-go?


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## Baaad65 (Aug 29, 2019)

So I'm glad you found the problem but I would shift into documenting everything with pictures, every pushrod every peice of sludge in the heads before you pull everything apart and clean anything. I hate to say it but now you have to be suspicious about the whole build so you need to build a case if this wasn't built correctly. I'm sure you paid a lot of money for this and there's no excuse for this happening on a brand new motor, do you have a build sheet of every part with numbers and every machining operation. Maybe you can replace the rods and it will all be good for a 100,000 miles maybe not. I've been in court with a contractor before and it helped with my stack of pictures and documentation. Sorry if it sounds like I'm jumping to conclusions but I'm saying just preserve the evidence that's all.


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## Baaad65 (Aug 29, 2019)

kevin1727 said:


> The builder is still blaming the carburetor. He says the rich condition fouled the plugs, causing detonation which damaged the push rods. But the plugs are not fouled now.


I never heard such a line of bullshit in my life, no detonation is happening with a rich condition like that and two plugs not firing. If all the plugs were white maybe, he's on the ropes because he knows he didn't do the job right. Tell him your contacting the BBB and hiring a lawyer to recoup your investment and then see what his reaction is. Time to switch to south paw Rocky!


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## kevin1727 (Aug 4, 2021)

RMTZ67 said:


> I would like to know if the lifters and cam are still good....from the engine break-in. Was it running like this from the get-go?


It's always been low power and smoking. I never noticed the knocking noise before but I never looked and listened really closely either. I didn't check much until just before the carb and plugs were replaced by the builder Aug 30th. I've had the car since May 3rd but hadn't driven it much. Only about 350 miles so far because there were lots of little things to fix on the car in the beginning.


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## RMTZ67 (Mar 12, 2011)

kevin1727 said:


> It's always been low power and smoking. I never noticed the knocking noise before but I never looked and listened really closely either. I didn't check much until just before the carb and plugs were replaced by the builder Aug 30th. I've had the car since May 3rd but hadn't driven it much. Only about 350 miles so far because there were lots of little things to fix on the car in the beginning.


Apart from taking it back to the builder, I would see if any of the forum members that live near you can assist you in maybe taking the intake off to take a look at your cam and lifters. I am assuming that if it is still under warranty he owns it. No matter what he says. Like Baddd said take pics and keep the forum posted...a judge would see its obvious the guys here are more capable of diagnosing your issues, than your engine builder...w/o even seeing your car lol. Take a deep breath....most of us have been there somewhat.


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## PontiacJim (Dec 29, 2012)

kevin1727 said:


> The builder is still blaming the carburetor. He says the rich condition fouled the plugs, causing detonation which damaged the push rods. But the plugs are not fouled now.



Bottom line in reading this post........your engine builder if FULL OF SHIT! Period.

You have 2 spark plugs that are not firing. You have 1 spark plug that looks wet. A rich condition is NOT going to cause detonation, just the opposite, a lean condition can cause detonation. Detonation would also show up on your plugs as small flecks from the aluminum from the piston melting. Detonation does not damage pushrods as the detonation occurs during the combustion process when both valves are closed. Detonation that bad would have been heard very easily. Bad timing can also cause detonation, but again, you would definitely hear it if it was that bad that it bent pushrods.

Coil bind can bend pushrods or the spring retainer hitting the valve guide. You can use a feeler gauge for this. As far as how much room should be between the coils, .060" is a good number.

The plugs do appear to be running rich, and that is a carb issue - not size issue, so don't believe his horseshit. 600CFM is fine for a street application and will work. The factory Q-jet was 750 CFM and some later Q-jets were 800CFM. The smoke you see may be from an over rich condition, but it should be black. If the engine was not broken in correctly, the rings may have not seated well or glazed the cylinder walls and you may end up with an engine that uses oil - but oil smoke is more a light blue and lingers. White smoke is typically auto trans fluid or anti-freeze. 

Pontiac stock bottleneck rocker arm studs get torqued down to 20-25 ft lbs. My experience with installing old, or even the new "crimped" rocker arm nuts is that they will back off. I used new crimp nuts on a previous 400CI build and had the nut back off and rocker go sideways just like yours. I bent the pushrod as well. Another one had also backed off but not to the point of the rocker going sideways. I took them off and went with the poly locks - end of problem. My rocker arm did not go sideways and pushrod bend because the engine was detonating! Such bullshit.

If you are using the 1.65 ratio roller rocker tips and high lift cam, you need to elongate the pushrod holes or the pushrods can hit and bend - or not seat as they should in the rocker arm cup. It is important to have the correct pushrod tip for the rocker arm used. Using the 1.65's will lift the valve higher and you want to have the correct valve springs and spring height. Coil bind can bend pushrods or the spring retainer hitting the valve guide because wrong springs, weak springs, or too short of a spring installed height. You can use a feeler gauge for this. As far as how much room should be between the coils, .060" is a good number.

If the pushrod tips are chewed up, you now have metal in the engine which is not a good thing, sorry to say.

Not trying to discourage you, but you have a clown working on your car and he is not going to want to be responsible for your engine and throw bullshit at you to try and side step any mistakes he may have done. You can't prove it unless you take the engine to another reputable engine builder, let him tear it down, and inspect it and give you his opinion on what may have been done incorrectly. Then and only then will you have any hard evidence and ammunition to go after him. Right now it is his word against you and he has the upper hand - even if it is bullshit he is throwing at you.


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## Baaad65 (Aug 29, 2019)

So I asked before do you have the build sheet on exactly what was done? Hate to give you more anxiety but I knew a transmission shop that would change the fluid, paint the trans and charge for a rebuilt or new one! Did you research this shop? At this point I would document everything, put all the rockers to torque spec and see how it runs and tune the idle mixture with the vacuum gauge...I bet that gauge will be steady. Then you can determine if anything else is wrong like the cam being wiped out. Also I would do a compression and leak down test, get all your ammunition together before confronting the shop.


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## sameold01 (Jun 21, 2020)

Maybe invite the engine builder to read this thread. Good job Kevin1727! Did the builder offer you any warranty on paper?


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## kevin1727 (Aug 4, 2021)

Assuming the valves, cam, and lifters are okay, what do I need to buy to fix this problem?
Poly-Locks?
Push Rods?
Is this something I can do without a lot of special tools?
Do I have to reset valve lash when I replace the push rods?


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## armyadarkness (Dec 7, 2020)

kevin1727 said:


> The builder is still blaming the carburetor. He says the rich condition fouled the plugs, causing detonation which damaged the push rods. But the plugs are not fouled now.


That's a blatant lie. 

If you recall earlier, I was discussing rocker adjustments and another member mentioned "arent they all torque to yeild". One of the exceptions to that is roller rockers, which you have. 

I suspect the builder simply torqed them, which is just asking for trouble. Roller need poly locks!

If you need help getting him to adhere to his obligations, call me.


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## armyadarkness (Dec 7, 2020)

kevin1727 said:


> Assuming the valves, cam, and lifters are okay, what do I need to buy to fix this problem?
> Poly-Locks?
> Push Rods?
> Is this something I can do without a lot of special tools?
> Do I have to reset valve lash when I replace the push rods?


Call me and I'll help you sort it all out. I think your cam and lifters will be fine.

Poly locks wouldve prevented this, so you need them and new pushrods. That entire job requires a single 9/16 wrench and an allen key. 

This is an easy thing to correct.

Your position with the builder should be that you had Pontiac experts evaluate the situation and that every detail has been recorded here in the file. You simply want what you paid for, and if he refuses, I can arrange to have a GM dealership give a written assessment of what occurred. Then you can simply file and get all of your money back.

But at this critical juncture, dont be hasty. Don't say anything more to the builder than you need to... and dont sell the car.


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## kevin1727 (Aug 4, 2021)

Okay, I need to clarify about the builder. He is a close relative and I can't destroy the relationship. There are also some extenuating family health issues that require I give him some leeway. 

He does build very nice cars. I have seen them and ridden in them. He says he will fix everything but I've had the car since early May and it's been a continuous string of issues from the AC install, wiring errors, broken or substandard parts, body assembly, and all these engine/carburetor issues. Selling the car would end the conflict, but I also realize I might go through fixing lots of problems with any other car I find unless I spend $100k. I just want a driver car, not a trailer queen.

I've already been firm with him about not swapping to the 600cfm carburetor and a few other items. 

The knowledge and information y'all have imparted to me is giving me the power I need to get him to fix things right. Yes, he has been a jerk about how much he knows a few times, but what I've learned here has put him in his place when he veers off on the shade-tree mechanic route. This forum has been invaluable, even if I have to sort through a little not-quite-right information.

I hope I can get this latest issue fixed with the help here and make sure it is done correctly. If I can do it without the builder, that is okay with me.


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## armyadarkness (Dec 7, 2020)

Glad you mentioned it!

In that case, lets get a pushrod length measurement...

And see what we can do to find you some new pushrods. Are the rockers all okay?

I suspect the cam and lifters will be fine.

Rollers really need polys, so we need to get them too. Installing it all is an entry-level job and it takes less than an hour. 

You'll need:

A socket to remove the valve covers.
Valve cover gaskets
Permatex Ultra Grey
A 9/16 wrench
An allen key


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## armyadarkness (Dec 7, 2020)

Then just let this builder go about his business, and let us guide your tuning.


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## armyadarkness (Dec 7, 2020)

kevin1727 said:


> He is a close relative and I can't destroy the relationship.


Yeah... tough, if not impossible to deal with family.


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## Baaad65 (Aug 29, 2019)

armyadarkness said:


> Glad you mentioned it!
> 
> In that case, lets get a pushrod length measurement...
> 
> ...


Also something picked up in the Noise thread is he needs a spring cap on #5 right? That will require a little more work and tools to keep the valve from dropping.


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## Baaad65 (Aug 29, 2019)

Maybe stick to one thread also and abandon the "Noise" thread so it doesn't get confusing and something gets missed.


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## armyadarkness (Dec 7, 2020)

sameold01 said:


> These older pontiac engines even up to 1969 don't you torque the rockers to 20 foot lbs if the valvetrain is all stock?


So now knowing what we know... yeah, obviously the valvetrain wasnt stock. It had rollers without poly's, which to me is a waste. And yes, if they were used/ old and torqued to 20, then that was the problem... Yeah, he could use regular lock nuts, but they at least needed to be new.

If he does get poly locks, we need to be sure that his valve covers will clear them.

This should be a cheap, easy job, just need to plan it right.


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## Baaad65 (Aug 29, 2019)

Also I would definitely do a couple of oil and filter changes and while you're getting that stuff I highly recommend a magnetic drain plug, it's cheap insurance and let's hope there's no pieces missing off those push rods.


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## RMTZ67 (Mar 12, 2011)

Need to drain the oil, maybe pour some diesel over the heads to flush out any metal particles.removing the intake and do the same might be good as well. Magnet drain plug and filter magnet. The metal is the iffy part.


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## RMTZ67 (Mar 12, 2011)

Baaad65 said:


> Also I would definitely do a couple of oil and filter changes and while you're getting that stuff I highly recommend a magnetic drain plug, it's cheap insurance and let's hope there's no pieces missing off those push rods.


We were thinking along the same line at the same time. That's what showing up to class does lol.


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## kevin1727 (Aug 4, 2021)

I've abandoned the noise thread. 

Okay, what are my next steps?

I'm guessing remove all the rocker arm nuts and rocker arms. Do I need to keep them all in order so they go back exactly where they came from?
Then remove all the push rods?

The rocker arms are new. They are from Comp Cams marked "165". 
The rocker arm studs are 7/16" thread. What Poly Lock do I need to buy?











Yes, I was looking at that one valve spring without a cap. The cap is broken loose and slid down the spring against the head. That is the video I posted way above called "Loose Rocker". Can I buy just a new cap?


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## ponchonlefty (8 mo ago)

kevin1727 said:


> Assuming the valves, cam, and lifters are okay, what do I need to buy to fix this problem?
> Poly-Locks?
> Push Rods?
> Is this something I can do without a lot of special tools?
> Do I have to reset valve lash when I replace the push rods?


if it damaged the push rods then inspect the rockers for damage. look to see if the heads have been clearanced for the 1.65 rocker.you need to check everything . paul spotts on ebay has polylocks or butler will set you up with what you need.


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## armyadarkness (Dec 7, 2020)

kevin1727 said:


> Yes, I was looking at that one valve spring without a cap. The cap is broken loose and slid down the spring against the head. That is the video I posted way above called "Loose Rocker". Can I buy just a new cap?


But the valve didnt drop? You abandoned the old thread, and now the pictures are gone... Shouldve left it up for reference.


Your rocker arms *dont* need to go back where they came from, but make sure none of them are damaged in the pushrod pocket.
You need 7/16 Poly locks, but they might interfere with your valve covers, especially since you're experiencing clearance issues with the brake booster. So, you might be better off with new oem style lock nuts.
Yes, the spring cap can be replaced, but you need to ensure the valve doesnt drop while doing so... which is fairly easy.
Assuming that your pushrods are correct, order replacements for the bad ones.


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## kevin1727 (Aug 4, 2021)

armyadarkness said:


> But the valve didn't drop? You abandoned the old thread, and now the pictures are gone... Shouldve left it up for reference.


The valve and spring look fine. It was just the cap that got chewed around the top. Maybe the top retainer on the valve spring too?

I didn't delete the other thread. I'm just not posting there anymore.


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## Baaad65 (Aug 29, 2019)

Are all the pieces of the spring cap there? And maybe when you dump the oil get a magnet and drag it around on the oil pan to the drain hole to make sure you collect any items that shouldn't be there.


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## kevin1727 (Aug 4, 2021)

Baaad65 said:


> Are all the pieces of the spring cap there? And maybe when you dump the oil get a magnet and drag it around on the oil pan to the drain hole to make sure you collect any items that shouldn't be there.


Quite a bit missing.


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## Baaad65 (Aug 29, 2019)

Yikes, well maybe they made there way to the bottom of the pan...get a magnet ready when you dump the oil and strain the oil. So does your builder know about this latest discovery and is he going to back you up on the parts? I know it's a sticky situation.


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## kevin1727 (Aug 4, 2021)

Would any of these work?









Rocker Arm Adjusting Nuts; High Energy™ Polylocks, 7/16" Stud


• Designed for ultimate strength and locking force• High Energy™ and Magnum polylocks are best for moderate lift and spring pressure applications • Hi-Tech™ Polylocks work well in all high end race applications • The stud girdle polylocks are precision




www.compcams.com












Rocker Arm Adjusting Nuts; Hi-Tech™ Polylocks, 7/16" Stud


COMP Cams®




www.compcams.com






https://www.summitracing.com/parts/cro-86050s-16?seid=srese1



I'm thinking the CompCams Hi-Tech for compatibility with the CompCams rockers.
But the Crower ones are listed as short. They are 1/8" shorter.


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## Jared (Apr 19, 2013)

Sorry about being late to the party today. First off, you're making the right decision. Close friends and family are more important than any car. Hopefully any metal that made it through the engine didn't cause too much damage. You may get lucky, you may not. There may not be much missing from that cap. It looks mushroomed out to me.

Now onto your engine. Did it look like the rocker was hitting the cap? If so, you need to find out why. Also, find out if the heads were clearanced for the 1.65 rockers. If they were, great, if not the easiest cheapest and option would be to pick up a set of 1.5 rockers and measure the correct pushrods for the new rockers. You will want to do this regardless. You have a flat tappet cam shaft so the only special tools you need to measure is one of these:



https://butlerperformance.com/i-24868533-comp-adjustable-pushrod-length-checker-5-16-8-500-9-800-cca-7902.html?ref=category:1459671



A pair of these:



https://butlerperformance.com/i-31643318-comp-light-checking-springs-set.html?ref=category:1459671



and one of these:



https://butlerperformance.com/i-31644101-valve-spring-compressor-head-on-stud-mount-steel-chrome-3-8-in-and-7-16-in-rocker-studs-each.html?ref=category:1459671



You will also need an air line with the spark plug threads on one end to pressurize the cylinder (or cylinders) you use to measure. Basically, you remove the valve springs and install the test springs. Set the length of the push rod length tool so that the roller tip is in the very middle of the valve stem. Order the correct length pushrods. I colored the top of the stems with sharpie and turned the engine over a few revolutions to ensure I had the correct length. It'll be a little harder to do with the engine on the stand, but it's doable. 

Here's what you want to see for the measurement. This was mine after breaking in the cam but before installing the inner springs.


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## Jared (Apr 19, 2013)

Also, after you get this put back together with the correct pushrods, check the valve springs for coil bind as @PontiacJim recommended. I know we are throwing a lot at you at once. I'm far for an expert at this but did assemble the top end of my engine myself. I don't want to guess on the poly locks. I'm running the Comp gold rockers on mine and they came with the correct poly locks.

None of this is hard to do, it just takes time. Old cars can be really rewarding and really frustrating. Mine has spent more time on stands in my garage than actually moving under it's own power. I have more miles on my back climbing under it than I've put on the clock.


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## ponchonlefty (8 mo ago)

kevin1727 said:


> Would any of these work?
> 
> 
> 
> ...


yes, i think they will. but you need to know how much clearance on your valve covers.


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## Sick467 (Oct 29, 2019)

I have read that many folks have poly lock nut interference issues with the thicker roller rockers and stock-like valve covers. An option is to go back to stamped rockers as I know they have polylocks that fit under stock valve covers on my 67 and my 70-76 franken-motor.

As you know, getting the stock valve covers off the engine can be a tight operation. Much taller valve covers means removing them will be a chore.

I would use some putty (or I hear a ball of tin foil works too)...measure the distance from the top of the stud to the top of and installed roller rocker (not the nut, but where the nut seats to the rocker),record that measurement, place the putty on the top of the rocker stud, set the valve cover (with gasket) on, push down on it to compress the ball of putty/foil, remove the valve cover, measure the room you have from the top of the stud to the top of your valve cover, and then search for polylocks that might live in that space...

Distance from the rocker/nut seat to the top of the stud *PLUS* the distance from the top of the stud to the top of your valve cover. Measuring the wad-o-stuff properly is not an exact science since it may push down around the stud and leave you with a hole, but can be done with some confidence. It may take several tries to get the wad-o-stuff the right size so that it does not squish too much and make the measurement difficult.

This is the available room you have for the polylocks...the tricky part is determining IF the set screw will stick out the top of the nut (when installed) and need more room. All you need is the set screw length and gathered measurements from above to figure this out.

For someone who has never done this sort of thing, it can read pretty confusion...it's not hard and once you have done it...you can use this concept in many other places. I'd ne glad to discuss it over the phone...PM me if you want...I'm glad to see you digging into this!


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## kevin1727 (Aug 4, 2021)

The saga continues....

Damaged cap.









Push rods. The three damaged rods were different from the rest. All the others had ball ends, but the damaged ones did not. Builder said it don't matter to have different ones but I told him apparently it does. I plan to buy a whole new set instead of letting the builder "find" some in his shop to replace the damaged ones. I only have a tape measure, but I'm measuring exactly 9-1/8". 









Some of the debris I removed. This looks like machining debris, not push rods pieces. The vast majority of what stuck to the magnet was more like fine sawdust.









This is what I heard. Push rod coming up and tapping the valve cover.









Everything else looks fine. I don't see any damage to any of the other caps, the springs, or the valve stem retainers.


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## ponchonlefty (8 mo ago)

kevin1727 said:


> The builder is still blaming the carburetor. He says the rich condition fouled the plugs, causing detonation which damaged the push rods. But the plugs are not fouled now.


thats not true.


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## Baaad65 (Aug 29, 2019)

kevin1727 said:


> The saga continues....
> 
> Damaged cap.
> View attachment 157317
> ...


Sooo what has the builder said about all this?


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## Baaad65 (Aug 29, 2019)

I've seen those spring caps before but not familiar with them, are they two pieces and how would the cap get beat up if that rocker was still on..or was it so loose the rocker went sideways beating it up? How long have you noticed the noise because you said you got it going in May?


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## Jared (Apr 19, 2013)

I didn't have a micrometer that was big enough to measure the pushrod on mine either so I used an adjustable T square and a micrometer to get the measurement as close as possible. I used the T square to measure full length, then used the micrometer to measure from a full inch mark to the adjuster to get as accurate as a measurement as I could. Based on what you can tell, did it look like the correct length was in there? You're going to have to pull the valve spring with the bad cap off anyway. Easy enough to make sure the geometry is correct while your at it.


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## Jared (Apr 19, 2013)

This goes without saying but if you end up going with different rockers, you will need to measure pushrod length. If you poled guys on here measurements would be all over the map with the different set ups.


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## PontiacJim (Dec 29, 2012)

kevin1727 said:


> The saga continues....
> 
> Damaged cap.
> View attachment 157317
> ...



I already pointed out this member's previous experience with the pushrods.









Central Virginia Machine Service (CVMS) Negative Review


WARNING! Do not send your engine to this hack! Well after almost a year of waiting to get this engine back from Jim L. @ CVMS including tearing it back down to a long block to fix things like rusted tins, cracked hub, leaking timing cover etc. I again had noise coming from the rockers and...




www.gtoforum.com





The shop that rebuilt the engine the 2nd time stated: " He found that the wrong push rods had been installed"

Another member also posted this: "I've seen the ends of stock pushrods chewed up before, and enough times that I won't put them back in an engine. They might live 250,000 miles mated to their original counterparts, but start changing things and increasing spring pressures and they crumble away within a few hundred miles. I haven't seen a problem with the originals that have the ball pressed into the ends like your bottom pushrod in the photo."

Hmmm, why did the ball end pushrods survive and the only three round tops get destroyed? You are sure you had oil going to the rocker arms? Look at the rocker arm cups to make sure they are good and not somehow made incorrect or not formed well.

Are those factory pushrod guide plates? I did read a post that said the Comp Cams pushrod guide plates were a little off and hit the sides of the pushrods. Any abnormal wear marks on the sides of the pushrods?

That piece in the photo is the OIL SPLASH GUARD. It is not a retainer or "cap." It simply keeps oil from splashing onto the valve stems. Pontiac uses a little more stem clearance than other makes to lubricate the valve stem. The splash guard keeps excessive oil off the stem.

The busted guard means the lifter has opened the valve high enough to clamp the guard between the head and spring retainer and beat the spring retainer right through the guard. These are often left off with a high lift cam for the reason you are seeing. If one is busted, my guess is others will be following. You cannot just remove them as they fit between the spring retainer and spring and act somewhat as a shim. If removed, the spring will effectively become "taller" which can mean a lowered spring pressure when the valves are closed. Too low on the closed spring pressure may lead to valves bouncing off their seats - this is why you want to match spring pressures, open/closed, to the cam/lift..

Most will choose to use Viton seals which maintain better oil control without the splash guards - but this means machining down the valve guides smaller in diameter so as to install the Viton seals. If you simply remove the splash shields, you may find the engine smoking /burning oil from any excess oil finding its way down the valve stem - sorta like when valve seals go and you start the car up and a puff of smoke dumps out the exhaust for a minute or two. So too late in the build to be machining the valve guides.

I will be surprised if you did not do any damage to the engine with the metal particles. Remove your oil filter,, dump what oil you can into a clean container and look for metal flecks. Then cut the top off the oil filter and pull out the filter media and look at it. This will tell you if you have metal particles in the engine. These particles will wipe out the oil pump, bearings, rear main seal, and score up the cylinder walls - among other things. You can try and flush the engine and see what happens and just go from there. Nothing to lose at this point. My oil pump check valve got stuck open with a piece of junk under it. Never had good oil pressure and kept losing it knowing I was in for an engine tear down. Finally after 7 years and 20K + miles, oil pressure went to 0. That was the end of that build.

My suggestions:

Get rid of the 1.65 roller rockers - apparently too much lift, probably don't have the correct matching valve springs (?), and someone never checked for coil bind or other clearances. Install a set of new 1.52 stamped steel rocker arms. You can go with the 1.5 roller tips if you choose. BUT, with the 7/16" Big Block rocker arm studs, you want to use the poly locks - stamped steel or roller tip.

Get an adjustable pushrod so you can check for the CORRECT pushrod length to get your rocker arm geometry correct. Do not guess on this one. I would get all new* ball end* pushrods based on the correct length needed. BUT, you want to use a solid lifter to get the correct length and that means pulling the intake/valley pan and replacing a hydraulic lifter with the solid lifter and then go about getting the correct pushrod length. BEFORE you feel this is more work, my concern here is that you stated the pushrod was hitting the valve cover. I would want to look at my lifter to make sure the spring clip that holds the guts in the lifter did not pop off and the lifter guts come apart. it would also be a good time to look at the bottoms of the lifters and your cam lobes to see it any metal particles got in there and caused any damage. OR, you could use a bore scope and look down the pushrod hole to check the lifter to make sure it did not com apart or has popped up and out and is laying in valley pan.

If all looks good and you get the correct pushrod length - which may be as stock - then reassemble the valley cover & intake. I would check every splash shield for damages/cracks. Replace the broken one. Install the new pushrods, 1.5 rockers, poly locks and adjust the valves. Put a white mark on each pushrod at the top where you can see it. The pushrod must be spinning with the engine running as this means the lifter is spinning on the cam lobe as it should be. If you don't see a pushrod spinning, it may be too tight/loose, need a little boost by manually spinning it with forefinger/thumb to get it going, or you have a bad cam lobe/lifter. I prefer to adjust the valves with the engine running - zero lash them as it is called and covered here on the forum.

Then watch your oil pressure as any metal that may have gotten in, if any did, can wipe out the oil pump. Bad oil pressure and it is game over - time to tear the engine apart.

Hopefully it will turn out all good, but take the time to check everything out. You don't want to damage the engine beyond repair when you could have taken it apart and replaced the wear parts.

Keep us posted.


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## Baaad65 (Aug 29, 2019)

kevin1727 said:


> The saga continues....
> 
> Damaged cap.
> View attachment 157317
> ...


Is there that much missing on those three push rods or are they that much shorter than the rest if so that's a lot. Looks like he grabbed whatever rods were laying around the shop.


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## Baaad65 (Aug 29, 2019)

PontiacJim said:


> I already pointed out this member's previous experience with the pushrods.
> 
> 
> 
> ...


I read that whole machine shop thread last night...what a nightmare 🤦‍♂️


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## PontiacJim (Dec 29, 2012)

Baaad65 said:


> I read that whole machine shop thread last night...what a nightmare 🤦‍♂️


What a disappointment after the shop had such a good reputation and then went down hill. The second rebuild went well. The OP contacted me a few months after the car was running and he was frustrated again and ready to sell the car. More engine issues - but it turned out to simply be a valve had gotten too tight and a valve adjustment got him back on the road and happy again.  I think we all have that frustrating moment and want to throw up our hands and walk away. LOL


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## ponchonlefty (8 mo ago)

Baaad65 said:


> I've seen those spring caps before but not familiar with them, are they two pieces and how would the cap get beat up if that rocker was still on..or was it so loose the rocker went sideways beating it up? How long have you noticed the noise because you said you got it going in May?


those are factory and fit the retainers. a'lot of racers just use the retainers. because of that very reason. i think those are like splash shields.


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## Jared (Apr 19, 2013)

The test weight valve springs will act the same as a solid lifter for checking pushrod length. They are so soft that the plunger on the lifter will not be depressed no matter what position the lifter is on the cam shaft. Basically, they are just strong enough to hold the valve closed and not much else. I preferred using them over trying to identify a solid lifter that was exactly the same as the hydraulic lifters I was using. Pick the wrong solid lifter and your measurements will be off. 

This seems to be a personal choice. There are a few ways that will yield the same results.


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## armyadarkness (Dec 7, 2020)

ponchonlefty said:


> yes, i think they will. but you need to know how much clearance on your valve covers.


THIS!


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## armyadarkness (Dec 7, 2020)

PontiacJim said:


> Get rid of the 1.65 roller rockers - apparently too much lift, probably don't have the correct matching valve springs (?), and someone never checked for coil bind or other clearances. Install a set of new 1.52 stamped steel rocker arms. You can go with the 1.5 roller tips if you choose. BUT, with the 7/16" Big Block rocker arm studs, you want to use the poly locks - stamped steel or roller tip.


I agree that if the engine wasnt prepped for the 1.6 rockers, it's going to be an issue... And, I do recall you telling me back in the day that I needed to use poly's on my 670's... so I bought the full rollers that @BearGFR recommended, and they came with poly's.

THAT BEING SAID!!!

Even with tall VC's, I had some contact... and I have a mini-brake-booster, so I can get my VC's on and off with ease.

Trying to use a tall cover with the full sized booster, is going to be a problem... 

For these reasons, stock stamped 1.5's make the most sense.


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## armyadarkness (Dec 7, 2020)

PontiacJim said:


> I think we all have that frustrating moment and want to throw up our hands and walk away. LOL


Youve seen me go through it many times


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## kevin1727 (Aug 4, 2021)

The push rods match what is spec'd for the engine. 9.13


ponchonlefty said:


> yes, i think they will. but you need to know how much clearance on your valve covers.


Looks like plenty of clearance. Top of the stud is 1.5" and the valve cover is 2.5" deep. I'm more concerned that the poly lock is long enough.


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## ponchonlefty (8 mo ago)

kevin1727 said:


> The push rods match what is spec'd for the engine. 9.13
> 
> Looks like plenty of clearance. Top of the stud is 1.5" and the valve cover is 2.5" deep. I'm more concerned that the poly lock is long enough.


i looked up the part number 4606-16 is supposed to work with stock rockers and roller tip. they make a 5/16 valve cover gasket to give a little more clearance. paul spotts sells on ebay under fbpaul.he has some. im not pushing the guy but i have bought from him before.hope this is helpful.


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## armyadarkness (Dec 7, 2020)

kevin1727 said:


> Looks like plenty of clearance. Top of the stud is 1.5" and the valve cover is 2.5" deep. I'm more concerned that the poly lock is long enough.


A typical "tall" VC is 3"... Some are 2.75"

Im just trying to save you any more aggravation!

As for pushrod clearance, the critical checkpoint when using 1.6 ratio's, is between the pushrod and head... because 1.6's will move the PR closer to the head.


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## armyadarkness (Dec 7, 2020)

If your builder didnt clearance the head for 1.6s, the pushrods couldve hung up on the head, causing the rocker arms to jump off of them.


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## armyadarkness (Dec 7, 2020)

But that would be apparent because the sides of the pushrods would be galled and scarred


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## armyadarkness (Dec 7, 2020)




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## kevin1727 (Aug 4, 2021)

armyadarkness said:


> But that would be apparent because the sides of the pushrods would be galled and scarred


Not galled and scarred, but polished. Is this not normal?


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## kevin1727 (Aug 4, 2021)

armyadarkness said:


> A typical "tall" VC is 3"... Some are 2.75"
> 
> Im just trying to save you any more aggravation!


I'm measuring inside clearance to match from the top surface of the gasket on the head to the top of the stud.


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## Baaad65 (Aug 29, 2019)

I think it depends where that polished area lands, is it where the guide plates are or the pushrod hole in the head. I don't think anything should be rubbing that much.


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## kevin1727 (Aug 4, 2021)

armyadarkness said:


> If your builder didnt clearance the head for 1.6s, the pushrods couldve hung up on the head, causing the rocker arms to jump off of them.


My guy said I must be mistaken about the rockers being marked 1.65. He said they are supposed to be 1.52. He says he normally has his engine builder do a short block but on my car he was trying to save time and let the engine builder do the long block. 

I sent a photo of the rocker number to my builder. So he is upset and very apologetic right now. He's even saying the carburetor must be okay. 

So it looks like we're doing new rocker arms, push rods, poly locks, and one new valve spring when he gets back in town.


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## kevin1727 (Aug 4, 2021)

Baaad65 said:


> I think it depends where that polished area lands, is it where the guide plates are or the pushrod hole in the head. I don't think anything should be rubbing that much.


The areas near the top with the black ring are at the guide plates. The areas farther down are inside the head.


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## armyadarkness (Dec 7, 2020)

__





Loading…






butlerperformance.com


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## armyadarkness (Dec 7, 2020)

As I mentioned, maybe more than you need, but its what bear and I use.


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## armyadarkness (Dec 7, 2020)

Definitely looks like there was contact with the head.


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## Baaad65 (Aug 29, 2019)

kevin1727 said:


> My guy said I must be mistaken about the rockers being marked 1.65. He said they are supposed to be 1.52. He says he normally has his engine builder do a short block but on my car he was trying to save time and let the engine builder do the long block.
> 
> I sent a photo of the rocker number to my builder. So he is upset and very apologetic right now. He's even saying the carburetor must be okay.
> 
> So it looks like we're doing new rocker arms, push rods, poly locks, and one new valve spring when he gets back in town.


That's good but is he willing to at least pay for the parts and you'll cover the labor? Hopefully this fixes everything and there's no damage to the motor. The carburetor IS probably ok but still to small, look into a 770 Street Avenger with an electric choke and vacuum secondary's that's what I started out with and it was a good carb. Or an Eddie


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## Baaad65 (Aug 29, 2019)

armyadarkness said:


> __
> 
> 
> 
> ...


That's what my motor came with before I went with the Scorpion Race 1.65


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## Baaad65 (Aug 29, 2019)

I can't remember if you gave the cam and spring specs because that would be helpful to know, along with all the specs of the motor like pistons.


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## armyadarkness (Dec 7, 2020)

Baaad65 said:


> That's good but is he willing to at least pay for the parts and you'll cover the labor? Hopefully this fixes everything and there's no damage to the motor. The carburetor IS probably ok but still to small, look into a 770 Street Avenger with an electric choke and vacuum secondary's that's what I started out with and it was a good carb. Or an Eddie


The builder is handling the valvetrain and he already has a new 750 eddy on there


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## armyadarkness (Dec 7, 2020)

Baaad65 said:


> That's what my motor came with before I went with the Scorpion Race 1.65


That makes sense, since it's what Butler recommends and they built your engine.


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## kevin1727 (Aug 4, 2021)

Baaad65 said:


> That's good but is he willing to at least pay for the parts and you'll cover the labor? Hopefully this fixes everything and there's no damage to the motor. The carburetor IS probably ok but still to small, look into a 770 Street Avenger with an electric choke and vacuum secondary's that's what I started out with and it was a good carb. Or an Eddie


We're all good right now. He's doing all the labor and parts for free at my house. I'm only paying for upgrade to poly locks.


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## Baaad65 (Aug 29, 2019)

armyadarkness said:


> The builder is handling the valvetrain and he already has a new 750 eddy on there


Guess I missed that, last I heard he had a 600cfm and the builder wanted to order a new 600.


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## Baaad65 (Aug 29, 2019)

kevin1727 said:


> We're all good right now. He's doing all the labor and parts for free at my house. I'm only paying for upgrade to poly locks.


That's great news


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## armyadarkness (Dec 7, 2020)

Baaad65 said:


> Guess I missed that, last I heard he had a 600cfm and the builder wanted to order a new 600.


Yeah, the thread has been all over the place, but no, he has a new 750


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## RMTZ67 (Mar 12, 2011)

Question....would it be necessary for him to do the breakin after installing factory rockers? or the cam and lifters should be set? Or is he going back to rollers?


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## RMTZ67 (Mar 12, 2011)

Baaad65 said:


> Guess I missed that, last I heard he had a 600cfm and the builder wanted to order a new 600.


Maybe playing hookey that day.


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## RMTZ67 (Mar 12, 2011)

armyadarkness said:


> Yeah, the thread has been all over the place, but no, he has a new 750


This has been interesting to say the least.


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## RMTZ67 (Mar 12, 2011)

Oops


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## Jared (Apr 19, 2013)

kevin1727 said:


> We're all good right now. He's doing all the labor and parts for free at my house. I'm only paying for upgrade to poly locks.


Glad this worked out for you and you were able to keep your relationship with your builder intact. 

One thing to consider. The stock spec pushrods only work on a completely stock engine build. Add roller rockers, or any other modifications, to the mix and that goes out the window. Changing the rocker studs from the bottle neck style to the screw in style changes this. Push rods on mine measured out to 9.450 inches which is way longer than stock. Based on the valve stem marks after breaking in the cam, the measurement was correct. The only thing this will slow down is ordering the pushrods after you have everything else on hand. The little bit of extra time is worth it at this point to make sure you get it right.


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## PontiacJim (Dec 29, 2012)

kevin1727 said:


> The areas near the top with the black ring are at the guide plates. The areas farther down are inside the head.



Exactly! Those pushrods were hitting the head. As pointed out by *Army*, the difference between the 1.5's and 1.65 is the pushrod cup is moved closer in towards the rocker arm stud which changes the fulcrum. In addition, it also causes more stress on the rocker arm stud at the pushrod has to push much straighter up on the rocker arm and that additional force pushes on the stud. One reason a stock bottle neck rocker arm stud can snap off when using the 1.65's and a larger lift cam that requires heavier springs. The RA IV engine did not use the bottle neck studs using the "041" cam, they used a 7/16" stud and a specific nut/lock nut/oil dripper/lock nut set-up from the factory. But, the heads were also clearanced with the elongated pushrod holes for the 11/16" pushrods as part of the factory head so the pushrods did not rub.

*Jared* is correct in using the aftermarket light valve springs on one set of valves on 1 cylinder to get your rocker arm geometry correct. You may be fine with what you have once you get the 1.5 rockers and the stock length pushrods will be what you need.

Just make sure you get as much of the metal pieces as you can. I might even put a strong magnet on the bottom of the pan below the oil pick-up screen to catch any tiny bits before the get sucked up and pass through the oil pump. Again, watch that oil pressure. 

Stick with us and we will get you straightened out.


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## PontiacJim (Dec 29, 2012)

RMTZ67 said:


> Question....would it be necessary for him to do the breakin after installing factory rockers? or the cam and lifters should be set? Or is he going back to rollers?



I would put some engine assembly lube on the tips of pushrods, on the rocker arm balls, and pour a little oil over the rocker arms. Cam and lifters should already be broken in.


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## Baaad65 (Aug 29, 2019)

Anybody else think a motor flush is a good idea? Guess you have to run it so kinda defeats the purpose. Only used that once in my BIL's 472 Caddy that was willed to him by his grandmother and sat for a long time. Don't know if anyone uses that stuff anymore? But I sure would be buying a magnetic drain plug.


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## RMTZ67 (Mar 12, 2011)

Baaad65 said:


> Anybody else think a motor flush is a good idea? Guess you have to run it so kinda defeats the purpose. Only used that once in my BIL's 472 Caddy that was willed to him by his grandmother and sat for a long time. Don't know if anyone uses that stuff anymore? But I sure would be buying a magnetic drain plug.


I used to run a gallon of diesel thru my engines and let it idle for one minute to kind of clean it out. Did it work? Not sure. Did it hurt? Not that I could tell. I bought two filter magnets and put one on my filter and one under the pan as as jim mentioned above, when I broke in my motor in case things went south...they are still there. Maybe run some cheap (Ha Ha) oil thru it, then drain the oil, run the diesel thru it then one more cheap oil...then the good stuff.


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## Baaad65 (Aug 29, 2019)

Diesel fuel? Wouldn't that wash everything to bare metal then score things? I know it has a lower ignition temp but that would make me nervous. Maybe pour some real thin oil all through the heads and drain it with a magnet in place, if there's something loose hopefully it will flow down into the pan. Good call on the magnet on the filter I never thought of that 👍


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## RMTZ67 (Mar 12, 2011)

Baaad65 said:


> Diesel fuel? Wouldn't that wash everything to bare metal then score things? I know it has a lower ignition temp but that would make me nervous. Maybe pour some real thin oil all through the heads and drain it with a magnet in place, if there's something loose hopefully it will flow down into the pan. Good call on the magnet on the filter I never thought of that 👍


I cant be the only guy here that did it. Diesel likely had more lubricant then. Add a quart of rislone to the diesel. 
The used filter use to have a qt of oil in it as well. Idle for (1) minute


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## Baaad65 (Aug 29, 2019)

RMTZ67 said:


> I cant be the only guy here that did it. Diesel likely had more lubricant then. Add a quart of rislone to the diesel.
> The used filter use to have a qt of oil in it as well. Idle for (1) minute


If you say so 👍


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## Jared (Apr 19, 2013)

RMTZ67 said:


> I cant be the only guy here that did it. Diesel likely had more lubricant then. Add a quart of rislone to the diesel.
> The used filter use to have a qt of oil in it as well. Idle for (1) minute


I've seen this done, but usually as a last resort on an engine that is completely gummed up. I'd be a bit hesitant on a fresh build. I'm not sure there is a great solution to get metal out of a fresh engine other than what's already been recommended, a few very strong magnets stuck in key locations. Maybe a few very short term oil changes.

That's the route I would take with it and hope for the best. Maybe keep it in the back of my mind that this build may only be good for a few years and plan for another in the future. Base that on oil pressure and sound. If it starts to get low or make internal engine noises, maybe time for a rebuild. Cheaper to do it before it drops to zero, or drops to zero and you keep running it.

With all of this in mind, I would not sell this car just because of this for a few reasons. First being it's a beautiful car that would be really hard to replace. Let's face it. there are way more GTOs left than Tempests and LeMans'. Second, and just as important, in good conscience, would you be able to sell this to someone else without telling the buyer everything you know about it which will affect the value. I know I wouldn't. It would keep me up at night. Third is that potential future rebuild will not sting near as much if you see it coming down the pipeline. You get to keep that what if spark going. I owned my car for 7 years when the engine let go. I had a larger engine in the back of my mind that entire time. Come in 2020, a couple loud bangs resulting in a 5 piece crankshaft and that dream is now a reality.

Sorry for rambling. I'm up early this morning and am a bit bored waiting to go to work. Have a great day guys!

...and good luck to @kevin1727. Keep us posted. We're all pulling for you and will help in any way we can.


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## armyadarkness (Dec 7, 2020)

Baaad65 said:


> Anybody else think a motor flush is a good idea? Guess you have to run it so kinda defeats the purpose. Only used that once in my BIL's 472 Caddy that was willed to him by his grandmother and sat for a long time. Don't know if anyone uses that stuff anymore? But I sure would be buying a magnetic drain plug.


No, because it's kerosene... which is okay to break up sludge, but on a new motor, the oil itself is the flush. He just needs to clear the debris, change the parts, change the oil, let it run in the driveway for 20 minutes, and change the oil again.

Then put 100 miles on it and change it again.


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## armyadarkness (Dec 7, 2020)

Baaad65 said:


> Diesel fuel? Wouldn't that wash everything to bare metal then score things?


What did you think FLUSH was? It's just diesel/ kersosene, which are both a form of oil and can lubricate at very low rpms. Neither can handle a load and neither would be good on anything new.


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## armyadarkness (Dec 7, 2020)

RMTZ67 said:


> I cant be the only guy here that did it. Diesel likely had more lubricant then


You're not the only guy. Anyone who ever used Gunk Motor Flush, was running diesel in their oil.


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## armyadarkness (Dec 7, 2020)

Jared said:


> I've seen this done, but usually as a last resort on an engine that is completely gummed up. I'd be a bit hesitant on a fresh build. I'm not sure there is a great solution to get metal out of a fresh engine other than what's already been recommended, a few very strong magnets stuck in key locations. Maybe a few very short term oil changes.
> 
> That's the route I would take with it and hope for the best. Maybe keep it in the back of my mind that this build may only be good for a few years and plan for another in the future. Base that on oil pressure and sound. If it starts to get low or make internal engine noises, maybe time for a rebuild. Cheaper to do it before it drops to zero, or drops to zero and you keep running it.
> 
> ...


I believe that he'll be fine, after all, as many of us know, these engines were put through Hell by their neglecting owners, back when they were new, and they're still here today.


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## Sick467 (Oct 29, 2019)

I have found minor amounts in machine shavings in, let's say, half of the 5 V8's I have rebuilt. The shavings were from the machine shop, I'm sure and were found in the oil filter after the first oil change. I bought a oil filter can opener just to check them out. It happens. For the most part, these oiling systems are made to catch these bits and pieces. That does not take away the worry when you know there's junk in there. I like Army's plan to do the initaial much more than recommended oil changes just to mitigate the worry. Magnets at the oil drain plug and on the filter too! No where else that could keep the bits staying in the engine upon the oil change.


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## Baaad65 (Aug 29, 2019)

armyadarkness said:


> What did you think FLUSH was? It's just diesel/ kersosene, which are both a form of oil and can lubricate at very low rpms. Neither can handle a load and neither would be good on anything new.


Like I said I used it once in the 80's...can't remember why I opened the refrigerator so how would I remember what the flush was made of 🤣


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## RMTZ67 (Mar 12, 2011)

Ya, I understand the hesitancy with diesel, but I would be more worried about metal than diesel. Either way, Kevin1727 will more than likely get plenty of use out of it with minimal cost to the engine and family.


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## Sick467 (Oct 29, 2019)

NOT that I have done this...If a flush would help ease the mind...I would not hesitate to run diesel or kerosene through it manually. Meaning fill it up, fill it up real high so that it gets the pistons and crank as wet as possible, pull the plugs, and use the distributor hole to run the oil pump with a drill...rotating the engine by hand while someone else runs the drill (all the while seeing diesel coming out at the rockers). IIRC you have to modify an old dizzy to take a drill chuck since part of the the dizzy shaft acts like an upper galley passage restriction. Without the dizzy, you can't get oil/diesel to the top of the engine. Come to think of it, I'd run the oil pump without the modified dizzy at first, by using a piece of round stock ground to fit the pump shaft. This would allow any junk to dump back to the pan sooner and not go to the upper engine...then use the dizzy to finish the flush. I think I just removed the gear and the upper guts so that a drill could be chucked to the top. There was some grinding I had to do to it, but can't remember what I went up to the loft to get...lol. I have it hanging on the wall, I'll check later when I head to the shop and post a pic if you want...just remind me. lol again!

This would allow a nice flushing that you could filter with a paint filter and piece of t-shirt as it was drained. No friction, no combustion, no heat...just flushing. The paint filter would tell you if it was necessary. If the filter shows bits...I'd take the filtered diesel and pour it back into the engine until it came out without any more bits.. I would repeat this by flushing with some cheap oil to get the diesel out and to prime the system with oil. The only thing that I can think that could go goofy is the high level of diesel fill might cause some diesel to escape out the dip stick tube hole or otherwise...not a killer, just a bit messy if it even happened.


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## Baaad65 (Aug 29, 2019)

He could also go buy an oil pump priming shaft like I did for 20.00 😉


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## armyadarkness (Dec 7, 2020)

Yes, many of these flushing methods are adequate for various applications, but at this point, he has already run the engine after all of this occurred.

Anything too big to pass will be in the VC's... anything small enough to leave the VC's will be in the oil pan. 

The builder, will be replacing the rockers, pushrods, and whatever else was damaged, then snaking whatever metal out of the pan that they can get.

I recommended that he pull the intake and valley pan for the installation of the new parts, so that the cam and lifters could be inspected, and then the final rocker adjustment could easily be made by verifying that the valves were closed.

At that point, any cleaner or marvel oil could simply be poured over everything with the oil drain plug open.

At the end of the day, he's not doing this work, the builder is, and despite the ball being dropped, based on my knowledge of the situation, the builder will do right by him.


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## geeteeohguy (Feb 2, 2008)

OK, I have to pipe in here. As a guy who has had decades of experience with commercially sold 'engine oil flush' kits, I DO NOT recommend them for use on ANY engine. On a newer engine, they strip oil and lube from rings and bearings, resulting in possible damage and premature wear. In the old gunked up engines, they are very effective at loosening the gum and tar and sludge so that it can circulate and plug oil galleys and oil pump pickups, resulting in spun bearings and ruined engines. Engine oil flush is yet another 'snake oil' product developed to generate easy revenue by repair dealers, and nothing else. The power steering flushes, brake flushes, transmission flushes, etc. are about the same. NO manufacture of vehicles recommends an engine flush....at least not since the 1930's. Have seen many engines damaged and many dollars wasted. That said, Fuel Injection and cooling system flushes are effective and prudent. End of rant.


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## Jared (Apr 19, 2013)

geeteeohguy said:


> OK, I have to pipe in here. As a guy who has had decades of experience with commercially sold 'engine oil flush' kits, I DO NOT recommend them for use on ANY engine. On a newer engine, they strip oil and lube from rings and bearings, resulting in possible damage and premature wear. In the old gunked up engines, they are very effective at loosening the gum and tar and sludge so that it can circulate and plug oil galleys and oil pump pickups, resulting in spun bearings and ruined engines. Engine oil flush is yet another 'snake oil' product developed to generate easy revenue by repair dealers, and nothing else. The power steering flushes, brake flushes, transmission flushes, etc. are about the same. NO manufacture of vehicles recommends an engine flush....at least not since the 1930's. Have seen many engines damaged and many dollars wasted. That said, Fuel Injection and cooling system flushes are effective and prudent. End of rant.


I agree with this.


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## ponchonlefty (8 mo ago)

Sick467 said:


> I have found minor amounts in machine shavings in, let's say, half of the 5 V8's I have rebuilt. The shavings were from the machine shop, I'm sure and were found in the oil filter after the first oil change. I bought a oil filter can opener just to check them out. It happens. For the most part, these oiling systems are made to catch these bits and pieces. That does not take away the worry when you know there's junk in there. I like Army's plan to do the initaial much more than recommended oil changes just to mitigate the worry. Magnets at the oil drain plug and on the filter too! No where else that could keep the bits staying in the engine upon the oil change.


when you get it back from the machining you need to take brushes through the oil galleries and wash with mild soap. then assemble at least that is the way i do it.


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## geeteeohguy (Feb 2, 2008)

ponchonlefty said:


> when you get it back from the machining you need to take brushes through the oil galleries and wash with mild soap. then assemble at least that is the way i do it.


Yes. Or laundry detergent. They make brushes for this, many gun-cleaning brushes and rods work great. (shotgun cleaning kit from Outers, etc. ) Brushing and rinsing the gallies and blowing them out clean is a MUSH. Then make sure to install all 3 oil galley plugs....the two behind the timing chain and that pesky one behind the freeze plug on the passenger rear side of the block. Many machine shops don't even remove that particular plug if they aren't familiar with Pontiacs, and leave it in. Remove it (hex key) and clean out the passage. On an old engine, sludge can form a slug at the end of the passage since it's a dead-end, and you will get lifter oiling issues on # 6 and #8 cylinders.


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## geeteeohguy (Feb 2, 2008)

*MUST (no edit function on this forum that I can find)


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## Baaad65 (Aug 29, 2019)

geeteeohguy said:


> *MUST (no edit function on this forum that I can find)


The three dots on the top right side of your post one is an edit button....I have to use it all the time 🤪


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## Baaad65 (Aug 29, 2019)

How far is he tearing this down ? I thought pushrods, rockers and fix one valve spring maybe the intake and valley pan.


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## PontiacJim (Dec 29, 2012)

RMTZ67 said:


> I used to run a gallon of diesel thru my engines and let it idle for one minute to kind of clean it out. Did it work? Not sure. Did it hurt? Not that I could tell. I bought two filter magnets and put one on my filter and one under the pan as as jim mentioned above, when I broke in my motor in case things went south...they are still there. Maybe run some cheap (Ha Ha) oil thru it, then drain the oil, run the diesel thru it then one more cheap oil...then the good stuff.


Kerosene is an old school method - often used by farmers. The older engines did not have oil filters and those that did, it was an often optional or add-on "by-pass" filter and only filtered a small portion of the oil. Photo of the 1948 International 6 with the by-pass filter which is connected to an oil pressure passage in the engine, filters through a cotton "sock" which basically looks like a toilet paper roll of yarn, and drains out the bottom into the oil pan.

Kerosene was used to flush the older engines. Some would just add a quart to the warmed up engine and let the engine idle only for about 10 minutes, then drain. Some would add the kerosene and drive the car - which seems to more than not cause more problems or damaged the engine. If you did not do this regularly and just added it after long miles, more of a chance of dislodging a lot if sludge/junk and plugging oil passages.

I have used, and still do on my 2015 Hyundai, Ford ATF. I warm the engine, add 1/2 Qt, idle for about 10 minutes, then drain. The variable timing on the Hyundai is controlled by a valve that has a small orifice where oil is used in changing the timing. If the small hole gets plugged with sludge, variable timing does not work as it should. So I used the ATF as a cleaner. Other cars of the past with the 5/6 Qt engines, I would add 1 Qt and let idle for 10 minutes or so. Never drive it and put a load on the engine as that is where problems can arise as it thins the oil. But, it does help keep the engine internals clean and unplugged. Again, if it has never been done, then I would use 1/4 Qt for a couple changes, then 1/2 Qt, and the a full Qt. You don't want to loosen any built up sludge/scale too quickly and plug up any small oil passages and have another engine problem on your hands.

Also leared this lesson. *NEVER EVER EVER* use a valve/piston spray into the air intake tube or throttle body with an aluminum cylinder wall engine! All the built up deposits on the valves and piston tops will break up and dislodge - just like the spray can cleaner states! HOWEVER, all the hardened deposits act as sandpaper on the cylinder walls of an aluminum engine and WILL score the cylinder walls. I went from 2200 miles to a quart (@ 163,000 miles) to 600 miles to a quart of oil overnight! There is no cure for this except an engine rebuild or replacement. So now I add a quart of oil ever 2 weeks and will never do another oil change again at this rate - just a filter every 4,000 miles. My car will not pass emissions so I now have to go through all the BS to get a yearly waiver. I thought the days of aluminum cylinders and lessons learned ended with the Chevrolet Vegas. No steel cyl liners and my machinist says no to even consider installing them as the engine was not designed for them - he told me I was F'd. LOL Dad had a '65 Chevy Impala 283CI he bought new and by 1978 it used a Qt every 100 miles, but the cheapo FleetWood oil back then was something like 69 cents a quart and the car was only used locally around town - until my brother blew up the engine, and installed a Corvette 327 for $150.00 with Dad being told it was another 283 with a 4-Bbl. LOL


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## Jared (Apr 19, 2013)

Baaad65 said:


> How far is he tearing this down ? I thought pushrods, rockers and fix one valve spring maybe the intake and valley pan.


As usual, this thread has gone slightly off the rails and we are now helping with things the OP doesn't need help with. This is now tech support for newly machined blocks. Come on Baaad! Can't you keep track? I have a slide rule, a graphing calculator, and a spread sheet going for this thread.


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## armyadarkness (Dec 7, 2020)

Jared said:


> As usual, this thread has gone slightly off the rails and we are now helping with things the OP doesn't need help with. This is now tech support for newly machined blocks. Come on Baaad! Can't you keep track? I have a slide rule, a graphing calculator, and a spread sheet going for this thread.


This was my fear yesterday and why I posted about it.

The OP has some strong family business that he's tending to, which bleeds into this mess, so his head is already overwhelmed, Im sure.

And he's expressed a few times in this thread that his knowledge, tools, and experience are limited.

I think it's *awesome* that this forum is filled with so many members who're trying to help, but we need to let @kevin1727 get the repairs done and then report back, before we can be of any more help. Otherwise, we're just adding to the confusion and burying the critical, relevant facts that this thread contains, under a mountain of fluff.


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## Sick467 (Oct 29, 2019)

Even though this thread is more than the OP needs/wants...It's full of great newbie advise that even get's into things that seasoned hobbyist can use. I've have worried some that the OP might get overwhelmed with all of our responses, but at least this thread didn't get as far into the weeds like some threads do. Threads are two fold...the OP needs help, and most forum members have a need to help. I know I enjoy sharing as much, or more, than getting answers. Maybe I should say... the fewer times that I need help and get it...it's really Great. The many times I offer help, it's really great too.


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## armyadarkness (Dec 7, 2020)

@kevin1727 Just reported to me that the repairs are already done and the car is as it should be!


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## kevin1727 (Aug 4, 2021)

Replaced all the wrong and defective parts, set the valve timing. Vacuum now steady at 15"Hg, idle is smoother, and no smoke. It sounds much better too. Car runs really great now and has no trouble spinning tires. There is a little hesitation when stepping on the gas that we have to work out but otherwise it's a day/night difference.

Thank you to everyone for all your help and suggestions, especially those telling me to not sell the car.


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## Baaad65 (Aug 29, 2019)

Jared said:


> As usual, this thread has gone slightly off the rails and we are now helping with things the OP doesn't need help with. This is now tech support for newly machined blocks. Come on Baaad! Can't you keep track? I have a slide rule, a graphing calculator, and a spread sheet going for this thread.


Ok I'll hang up and watch from the sidelines 😉


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## RMTZ67 (Mar 12, 2011)

Hopefully you can still make a car show or two before winter sets in.


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## 67ventwindow (Mar 3, 2020)

Baaad65 said:


> Ok I'll hang up and watch from the sidelines 😉


 What no breathers?????


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## Jared (Apr 19, 2013)

Baaad65 said:


> Ok I'll hang up and watch from the sidelines 😉


I was joshing you Baaad. It's not everyday I get to make a nerdy joke around here. You never know when the OP will need breather advice (or pictures).


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## kevin1727 (Aug 4, 2021)

So glad my car is now running good. Took it out for a little cruise today.


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## Sick467 (Oct 29, 2019)

Very glad it has turned out good...I have been kicking myself for not making an offer when you were down...lol Those 64's are fantastic and yours is a looker!


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## Baaad65 (Aug 29, 2019)

Man that's beautiful ! Aren't you glad you didn't sell it...until the next problem 😄 Are those American Racing VN501 wheels like mine? I love the big Tempest and the 428 badging 👍 Did you ever consider a gto hood? Glad it all worked out and hopefully your relationship is still in tacked with the builder. Boy this thread kept everyone on the edge of their lawn chairs 😉


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## PontiacJim (Dec 29, 2012)

Baaad65 said:


> Man that's beautiful ! Aren't you glad you didn't sell it...until the next problem 😄 Are those American Racing VN501 wheels like mine? I love the big Tempest and the 428 badging 👍 Did you ever consider a gto hood? Glad it all worked out and hopefully your relationship is still in tacked with the builder. Boy this thread kept everyone on the edge of their lawn chairs 😉


It is perfect the way it is, very smooth. Like the painted post, really brings out the roof drip rail moldings.


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## kevin1727 (Aug 4, 2021)

Baaad65 said:


> Man that's beautiful ! Aren't you glad you didn't sell it...until the next problem 😄 Are those American Racing VN501 wheels like mine? I love the big Tempest and the 428 badging 👍 Did you ever consider a gto hood? Glad it all worked out and hopefully your relationship is still in tacked with the builder. Boy this thread kept everyone on the edge of their lawn chairs 😉


Yes, American Racing VN501. I thought they had a similar retro look to the Rally II wheels.
I remember your photo with those wheels when I was deciding what wheels I wanted. I'm glad I got them.
Haven't looked at doing a GTO hood for it, but a lighter one would be nice, LOL.


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## kevin1727 (Aug 4, 2021)

PontiacJim said:


> It is perfect the way it is, very smooth. Like the painted post, really brings out the roof drip rail moldings.


Thank you for that suggestion this past year! Welded strips to replace the aluminum trim just like you said to do. I like the little less chrome. Just enough now to set off the lines.


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## kevin1727 (Aug 4, 2021)

Baaad65 said:


> ....hopefully your relationship is still in tacked with the builder.....


Yes, it was delicate, but everyone's knowledge here helped me convince him it wasn't a carburetor problem. 
Y'all helped save both my car and that relationship.


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## kevin1727 (Aug 4, 2021)

RMTZ67 said:


> Hopefully you can still make a car show or two before winter sets in.


It's perfect weather right now for them. Mostly cruise-ins going on. I might try to hit one tomorrow. I feel like I'm safe driving the 45 minutes to get there now.


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## Baaad65 (Aug 29, 2019)

Not to kill your buzz but did you do a couple of oil and filter changes and if so did you find any interesting in the oil or filter?


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## Baaad65 (Aug 29, 2019)

....by the way I love the stance of the car too, that's how have mine now 👍


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## RMTZ67 (Mar 12, 2011)

kevin1727 said:


> It's perfect weather right now for them. Mostly cruise-ins going on. I might try to hit one tomorrow. I feel like I'm safe driving the 45 minutes to get there now.


Nothing left to it, but to do it.... Enjoy.


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## kevin1727 (Aug 4, 2021)

Baaad65 said:


> Not to kill your buzz but did you do a couple of oil and filter changes and if so did you find any interesting in the oil or filter?


Doing that after I get my filter today. I've been unable to find one in stock locally so I order them online. This will be the fourth oil change in less than 500 miles on the car. I was thinking about driving a little more today to make sure everything is washed to the oil pan and the cylinders are blown out more. I'm pretty sure I got whatever came off the push rods when I ran a magnet around the valve springs. It was a lot of debris there and I don't believe what's left will be any problem. 
I have a high power magnet on a small probe that I'll put through the oil drain hole and see if anything is in the pan. I'm sure I'll get something from the original machining too.


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## kevin1727 (Aug 4, 2021)

Checked rockers again after driving. They are all good so the poly locks are doing their job. 
Checked compression. All cylinders are 135psi cold plus or minus 3psi.


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## kevin1727 (Aug 4, 2021)

Next problem to solve is the hesitation.
Reminder, 750cfm Edelbrock, 428 with performance cam.

It's really hard to get moving without stalling. Under 900 rpm and I just tickle the throttle to get moving, the rpm drops and will stall unless I let off the gas. Once it's fully hot it's better but still hesitates. 

Vacuum is
12.5 at 1,000 rpm.
11.5" at 900 rpm.
10.5 at 800 rpm. I start noticing the metering rods moving at this point.
10" at 700 rpm. More metering rod movement.
9" at 600 rpm. Metering rods chattering all the way up and down at this point as the engine rpm varies plus/minus 20 rpm.
7" at 500 rpm. This is the lowest car will idle with the idle screw backed out all the way.

Base timing is 16 degrees.
I've checked thoroughly and there are no vacuum leaks.

I set idle in park to 850 rpm.
Idle is between 600 and 700 when in gear. I'm thinking the jets are opening too much in comparison to the throttle plates at this vacuum and flooding the engine when I tickle the gas and the vacuum drops even more.

I'm guessing that's why the car will jump if I give it half throttle and get past the hesitation point when it's fully warmed?

That means I need stiffer springs in the jets? Edit: OOPS, I meant weaker springs to keep the jets closed more.


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## Sick467 (Oct 29, 2019)

It sounds like the accelerator pump needs adjusted. My Edelbrock (#1407) has three holes for the accelerator pump lever. My engine had a slight bog when giving it the initial gas pedal to take off from a stop light (normal old man driving). Once it bogged a bit and the gas pedal was pushed a bit further, it would recover and act like nothing was wrong. I ended up moving the accelerator lever to the topmost hole and adjusted the accelerator pump screw per their instructions. This made a big improvement; the bog was still there occasionally. As a last-ditch effort, I straightened the accelerator pump lever out just a bit...bog gone. The next step was changing something in the pump/carb...I think springs, but I did not have to go there.

The accelerator pump helps the carb make the transition from the idle circuit to the mid-range circuit. Mine was not pumping enough gas to make the transition.


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## kevin1727 (Aug 4, 2021)

Sick467 said:


> It sounds like the accelerator pump needs adjusted. My Edelbrock (#1407) has three holes for the accelerator pump lever. My engine had a slight bog when giving it the initial gas pedal to take off from a stop light (normal old man driving). Once it bogged a bit and the gas pedal was pushed a bit further, it would recover and act like nothing was wrong. I ended up moving the accelerator lever to the topmost hole and adjusted the accelerator pump screw per their instructions. This made a big improvement; the bog was still there occasionally. As a last-ditch effort, I straightened the accelerator pump lever out just a bit...bog gone. The next step was changing something in the pump/carb...I think springs, but I did not have to go there.
> 
> The accelerator pump helps the carb make the transition from the idle circuit to the mid-range circuit. Mine was not pumping enough gas to make the transition.


I've tried all three positions without any difference. I may have to take the top of the carb off to inspect it. It's a new carb though.


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## Jared (Apr 19, 2013)

The Edelbrock carbs are fairly easy to tune. No need to remove the carb to do most changes to them. You can play around with different metering rod sizes and spring rates in about 3 minutes without removing the carb from the car. A 500 rpm idle may be too low for the cam you're running. My cam is a few ticks more radical than yours and mine won't idle any lower than ~850 rpm.

16 degrees initial advance may be too much. You may want to find out what the timing is at ~3000 rpm and dial it back a few degrees. You don't need any special tools to do this, or a degreed damper. You can measure the circumference of the damper with a sewing tape measurer. Divide that measurement by 360 and multiply is by 36. Put a thin line on the damper at that measurement and see where it lands on your timing tab when you are fully advanced. Most important thing here. If you "borrowed" the sewing tape from your wife, you better return it before she realizes what you did with it.


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## kevin1727 (Aug 4, 2021)

Jared said:


> The Edelbrock carbs are fairly easy to tune. No need to remove the carb to do most changes to them. You can play around with different metering rod sizes and spring rates in about 3 minutes without removing the carb from the car. A 500 rpm idle may be too low for the cam you're running. My cam is a few ticks more radical than yours and mine won't idle any lower than ~850 rpm.
> 
> 16 degrees advanced may be too much. You may want to find out what the timing is at ~3000 rpm and dial it back a few degrees. You don't need any special tools to do this, or a degreed damper. You can measure the circumference of the damper with a sewing tape measurer. Divide that measurement by 360 and multiply is by 36. Put a thin line on the damper at that measurement and see where it lands on your timing tab when you are fully advanced. Most important thing here. If you "borrowed" the sewing tape from your wife, you better return it before she realizes what you did with it.


If I set for 850 in gear, that's almost 1,100 in park and it slams the transmission. It will idle at 500 but it's a rough idle. That's why I went with the 850 in park. I can use 900 too but it doesn't make any difference in the hesitation.

I've got a dial back timing light so all I need is the zero mark on timing.

I don't have the extra springs and metering rods. Those were in a kit that my builder has. I'll have to get the kit from him next week to try different combinations.

I'll try retarding the timing next. Just finished some accelerator pump checks. Everything looks good inside the carb.


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## Jared (Apr 19, 2013)

kevin1727 said:


> If I set for 850 in gear, that's almost 1,100 in park and it slams the transmission. It will idle at 500 but it's a rough idle. That's why I went with the 850 in park. I can use 900 too but it doesn't make any difference in the hesitation.
> 
> I've got a dial back timing light so all I need is the zero mark on timing.
> 
> ...


Ah, Forgot yours was an automatic. Sounds like you have that set correctly. 1100 is too high and you'd risk dieseling when you shut it down at that rpm. Your 500 rpm probably feels pretty similar to mine at 850. Again, should be fine.

This is the fun part of the project. Dialing it in takes time. Try to resist the urge and make too many changes at once, and take detailed notes on the effects of each change you make. It took me the first 500 miles on my new engine to get it set where the car was happy. And that 500 miles consisted of a lot of 10 mile drives coupled with quite a bit of disappointment.


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## kevin1727 (Aug 4, 2021)

Okay, the last change I was made was the accelerator pump. Reading another thread on the forum said they straightened out the accelerator pump arm a little. I did that and the hesitation is a lot less. When checking the accelerator pump I noticed there is a long slot along the side of the pump housing wall and straightening the arm probably got me a little lower and past the slot?


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## PontiacJim (Dec 29, 2012)

kevin1727 said:


> Okay, the last change I was made was the accelerator pump. Reading another thread on the forum said they straightened out the accelerator pump arm a little. I did that and the hesitation is a lot less. When checking the accelerator pump I noticed there is a long slot along the side of the pump housing wall and straightening the arm probably got me a little lower and past the slot?


You probably want to go bigger on the accelerator squirter on the 428/big cam. The ones out of the box are probably too small for your application. You can buy a kit with three different sizes. I'd put the biggest in first then see if that fixes it.





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www.summitracing.com


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## armyadarkness (Dec 7, 2020)

This is what I was talking about on Friday. It's easy to get so excited when you complete a goal, that you forget all of the other ones in line behind it.

Lately Ive been hearing from a lot of guys in the forum, who're chasing their tails because they over look a big, obvious, incompatible-part or setting.

My engine with 670 heads/ 93 octane takes a lot of base timing to smooth out the idle. With the same cam you have (I believe), I idle at 750-780, happy as a clam.

As for the base settings on that carb... assuming there are no vacuum leaks and that the choke is definitely set properly (yes Ive seen Eddy carbs where the choke was set to only open half way), then you'll:

Hook up the vacuum gauge and set the idle mixtures for the highest vacuum.
Install the lightest springs available in the needle jets, regardless of anything else. With your vac that low, the needles will come out of the seats before you want them.
Drop a size on the needles. If that doesnt do it, go up a size on the mains and needles.
What dizzy do you have? Vacuum advance? And yes, as Jim said, largest pump shot.

Keep in mind that with the AVS2 carbs, the air valve is also adjustable!


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## Sick467 (Oct 29, 2019)

kevin1727 said:


> Okay, the last change I was made was the accelerator pump. Reading another thread on the forum said they straightened out the accelerator pump arm a little. I did that and the hesitation is a lot less. When checking the accelerator pump I noticed there is a long slot along the side of the pump housing wall and straightening the arm probably got me a little lower and past the slot?


 Straightening the rod out a bit just takes some of the slop out of the mechanism and causes the pump to react a bit sooner, pushing fuel a bit sooner, and thwarting the stumble. I must have been on the edge of needing a different squirter (as PontiacJim mentioned), but got away with just tweaking the rod.

I'm not carb expert, but I think the changing the springs and metering rods effects a different circuit, not the idle to low range. I'd put my money on the squirter.


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## armyadarkness (Dec 7, 2020)

Sick467 said:


> I'm not carb expert, but I think the changing the springs and metering rods effects a different circuit, not the idle to low range. I'd put my money on the squirter.


The needles sit in the main jets, so they control cruise and the transition from idle mixture to mains.

The needle springs are what push the needles out of the mains, and engine vacuum is what keeps the needles in the seats. You want the spring rating to be half what your idle vacuum is. If the springs are too stiff, then the needles will come out to early and dump too much fuel... springs too soft and the needles wont come out soon enough.

This is why you often hear that the springs in an Eddy dont affect mixture, they only affect drivability. The needles are what set off idle and cruise.

In addition to the accelerator pump, they're a very good spot to look for a stumble off idle.


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## armyadarkness (Dec 7, 2020)

Idle circuit is set by the mixtures first, and then the idle adjustment.
Off idle and cruise are controlled by the pump and then primarily the needles. "How much fuel" is momentarily determined by pump shot length (which hole is the link in?) and then constantly controlled by the needles. "When and how" you get the needles, is determined by the springs.
Once the needles are out of the seats, the size of the main jets controls cruise to mids.
Secondaries are obviously for WOT.
Most importantly, one change to any of these things, can cause everything else to need resetting. Carbs were carefully designed so that each area overlapped the next, so you may think you have a perfect setting, which is actually masking the real problem.

If your idle mixture is to high, you can cheat it with a high idle setting. Mains too small can be masked with needles to small...

It's very important to understand it all. Have an AFR gauge and an onboard vacuum gauge (if possible). Take notes on changes and settings and address one area at a time.

WOT is easy to tune, because there's not much going on there. When you're going 70 mph and nail it, if the car responds well, then your air flap and secondaries are probably great. 

Idle and cruise are the most critical, becasue coming off those to areas is where you're most going to notice an issue. If you're going to race, it's most likely going to be off the line or a roll on from highway cruise.

This is why you hear that most carb issues are timing related, which isnt really true, but certainly worth noting.

It's why dizzy's without vac cans are horrible for the street. From a performance stance, they're absolutely useless unless you're at WOT the entire time.

At idle and cruise, a vac can add's at least (and preferably) 10 degrees of advance, so you can add more fuel, and when you stomp on the gas at idle or from a 50 mph cruise, that advance and fuel are what make you win,lose, or stall.


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## Sick467 (Oct 29, 2019)

armyadarkness said:


> The needles sit in the main jets, so they control cruise and the transition from idle mixture to mains.
> 
> The needle springs are what push the needles out of the mains, and engine vacuum is what keeps the needles in the seats. You want the spring rating to be half what your idle vacuum is. If the springs are too stiff, then the needles will come out to early and dump too much fuel... springs too soft and the needles wont come out soon enough.
> 
> ...


I stand corrected and educated...Thanks Army!


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## armyadarkness (Dec 7, 2020)

Sick467 said:


> I stand corrected and educated...Thanks Army!


You werent far off. The accel pump is certainly there, specifically for that reason... to address stumbles, but like I went on to say, it's easy to mask carb issues with the wrong adjustments, and on that note...

Although the squirter is made to address "off idle" transitions, no squirter setting that there is, on any Eddy or Holley, will make up for having the wrong needles and mains.

This is why AFR gauges are so good. EXAMPLE:

Cruising down the highway at 75 mph, my vacuum is at 22hg, the oil pressure is 70psi, temp is 160 degrees, engine is purring harmoniously with a 14:1 AFR.

I nail the gas and my AFR drops to 8:1, and then immediately goes to 13.2:1

What this tells me is that my AFR's are good, but my transition from cruise to secondaries is off, so I know that either my squirter or air flap need adjustment. If OTOH, my AFR stayed rich after punching it, then I would know my secondaries were too big.

Carters/ Edelbrocks somehow developed a rep for not being performance oriented, but many GTO's came with them from the factory. Any carb which is adequetly sized and gives you total control over idle, cruise, mid range, and WOT, can be tuned to perfection if you just know where and when you should be paying attention.


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## geeteeohguy (Feb 2, 2008)

Very nice little write-up, Army. Succinct, to the point, and accurate. For a Weights and Measures guy, you're pretty sharp on the Tune and Fuel, IMO! LOL....
Seriously, well stated.


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## Sick467 (Oct 29, 2019)

For somebody who has lifelong careers in so many non-auto related fields (lol), armyadarkness has it going on with tuning. I'm glad to be a member here alongside him! Among others, of course!


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## Baaad65 (Aug 29, 2019)

Sick467 said:


> For somebody who has lifelong careers in so many non-auto related fields (lol), armyadarkness has it going on with tuning. I'm glad to be a member here alongside him! Among others, of course!


You just want a ride on his Kubota Judge 🤣


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## kevin1727 (Aug 4, 2021)

armyadarkness said:


> This is what I was talking about on Friday. It's easy to get so excited when you complete a goal, that you forget all of the other ones in line behind it....


Oh, there are so many things to do. 



armyadarkness said:


> What dizzy do you have? Vacuum advance? And yes, as Jim said, largest pump shot.


HEI distributor (no points), with air can.
How much advance should I get from the vacuum? I'm seeing about 5 degrees at idle (850rpm in park). Since I'm not getting a lot of vacuum, should I adjust the air can on the dizzy to make up for that?


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## armyadarkness (Dec 7, 2020)

geeteeohguy said:


> Very nice little write-up, Army. Succinct, to the point, and accurate. For a Weights and Measures guy, you're pretty sharp on the Tune and Fuel, IMO! LOL....
> Seriously, well stated.


My mentor used to joke that the only qualification for being a weights and measures officer was that you could fog a mirror. While it seemed like a joke at the time, in my career, I found that the majority of my fellow officers could not possibly have passed that test. Nevertheless, it was civil service, so you really only needed to "know someone" to get the job... being alive wasnt a requirement.. in fact, Im quite sure that New Jersey has had many dead people on the civil service tests!

Fortunately for me, my neighbor owned the local speedshop when I was a kid, and he also owned Predator Carburetors (as well as Steffs Oil Pans, Hamburgers Oil Pans, and SLP Performance... they were all in my little town), and me and all my buddies worked there. So going on to a career in calibration, was harmonious.

Unfortunately, I was never able to apply any of it to my own cars, because my timing was off, but spending the last few years on this forum has brought it all full circle. Usually you get the knowledge first and then the experience. It was in reverse of that for me... but I learn something new here every day.


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## armyadarkness (Dec 7, 2020)

Sick467 said:


> For somebody who has lifelong careers in so many non-auto related fields (lol), armyadarkness has it going on with tuning. I'm glad to be a member here alongside him! Among others, of course!


As I mentioned, I was obsessed with cars as a kid and worked in speed shops, which is where I learned to weld. Through my career in law enforcement/ consumer protection, I kept doing all of that behind the scenes. And then of course, as a result I was in charge of all of the auto related fraud for the state... since literally none of the other officers knew what the Hell they were looking at. I had to inspect and license 25 dealerships, 160 gas stations, 125 tankers, and 370 repair facilities annually, and resolve all consumer complaints against them.

There were only 100 of us in the whole state, and 90% of them were college kids that wouldnt know a wrench from a toaster, so everything fuel or auto related came through me. The stories I could tell!

27 years of inspecting/testing/calibrating jewelry, forensic, and pharmaceutical lab equipment, fuel pumps, slot machines, parking meters, and money counters taught me a lot. You had to fully understand how everything worked, in order for you to spot when the operators were trying to cheat with them.

And since @PontiacJim taught me everything there is to know about GTO's, if I can just figure out redheads, I can finally run against Yoda for Jedi Council


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## armyadarkness (Dec 7, 2020)

kevin1727 said:


> Oh, there are so many things to do.
> 
> 
> 
> ...


In my opinion, you're not going to get optimal performance out of your setup with that dizzy... nevertheless, it will do the job nicely!

And....... Are we so sure that you dont have a lot of vacuum? I know you didn't before, but that was valve related and we have now fixed that. You should have 15hg of vac, and shoot for 10 degrees of advance off the can. 

Yes, you can "try" to adjust the vac can on the dizzy... assuming that it's the adjustable type, however, keep in mind that adjustable cans are ONLY adjustable for the AMOUNT of timing, and NOT WHEN you get it. Its not always an issue, but it can be.


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## kevin1727 (Aug 4, 2021)

armyadarkness said:


> In my opinion, you're not going to get optimal performance out of your setup with that dizzy... nevertheless, it will do the job nicely!
> 
> And....... Are we so sure that you dont have a lot of vacuum? I know you didn't before, but that was valve related and we have now fixed that. You should have 15hg of vac, and shoot for 10 degrees of advance off the can.
> 
> Yes, you can "try" to adjust the vac can on the dizzy... assuming that it's the adjustable type, however, keep in mind that adjustable cans are ONLY adjustable for the AMOUNT of timing, and NOT WHEN you get it. Its not always an issue, but it can be.


The numbers I posted on #277 above are after the push rods were fixed and rockers adjusted. About 11" at idle of 850rpm. I read elsewhere that with the valve lift and 4 degrees retarded cam I'm running, that number may be typical.








Engine Vacuum Troubleshooting


Years ago, a good friend introduced me to using a vacuum gauge to diagnose engine problems, in fact, it was often the first tool he would reach for when confronted with a poorly running engine.




www.classiccarrestorationclub.com


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## armyadarkness (Dec 7, 2020)

kevin1727 said:


> I read elsewhere that with the valve lift and 4 degrees retarded cam I'm running, that number may be typical.


Sounds odd to me, but Im far from a cam expert. Id like to see what your vac is, once your timing curve is optimized.

Dont we have the same cam?


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## kevin1727 (Aug 4, 2021)

armyadarkness said:


> Sounds odd to me, but Im far from a cam expert. Id like to see what your vac is, once your timing curve is optimized.
> 
> Dont we have the same cam?


I haven't messed with the full timing curve. I'm just working on the low speed hesitation right now (under 1,000 rpm) where the advance springs don't make much difference if any at all. There's not much to adjust. Idle mixture, accelerator pump, and timing, right? I can't get to the air can diaphragm internal adjustment (if there is one) unless I rotate the distributor since the air can is pointing at the head. I don't see any difference in the hesitation when moving the vacuum advance from ported to non-ported. 

Here's the typical scenario: I'm driving up my gravel road at 10 to 15 mph and the road rises slightly. I cannot get up the rise unless I either approach it at 20mph or I give it more than a little throttle and spin tires up the rise. I have to drive in a gear that gives me 1,500 rpm or more to go up any rise. It will not go up any hill at 1,000 rpm or lower and will stall under slight throttle. Playing with the accelerator pump arm helped quite a bit so I'm leaning towards getting the bigger accelerator pump jets. I'm going to open the carb and lubricate the accelerator pump right now. I saw that here.








Hesitation or Bog?


Click this link to return to eBay



jgronoj.weebly.com





The idle mixture screws don't make any noticeable difference between 3/4 and 2-1/2 turns so I set to 1-1/2 turns. This seems odd to me. 

Vacuum is proportional to rpm. I don't hit 20" until 1,600rpm.

I'm at 17 degrees base timing and 22 degrees with vacuum line connected to the distributor with 11" vacuum at 850 rpm. I don't know why my vacuum is so low. I can plug every port on the carburetor and it is the same. I've tried spraying starter fluid all around the intake areas and plugged ports and can't find a leak. Where else can there be a leak?

Here's my cam.


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## armyadarkness (Dec 7, 2020)

kevin1727 said:


> I haven't messed with the full timing curve. I'm just working on the low speed hesitation right now (under 1,000 rpm) where the advance springs don't make much difference if any at all. There's not much to adjust. Idle mixture, accelerator pump, and timing, right? I can't get to the air can diaphragm internal adjustment (if there is one) unless I rotate the distributor since the air can is pointing at the head. I don't see any difference in the hesitation when moving the vacuum advance from ported to non-ported.
> 
> Here's the typical scenario: I'm driving up my gravel road at 10 to 15 mph and the road rises slightly. I cannot get up the rise unless I either approach it at 20mph or I give it more than a little throttle and spin tires up the rise. I have to drive in a gear that gives me 1,500 rpm or more to go up any rise. It will not go up any hill at 1,000 rpm or lower and will stall under slight throttle. Playing with the accelerator pump arm helped quite a bit so I'm leaning towards getting the bigger accelerator pump jets. I'm going to open the carb and lubricate the accelerator pump right now. I saw that here.
> 
> ...


Your cam is much smaller than mine is and so I do not think that your vacuum is correct at all. If I have 15 with this, you should have 18 with that... 

Are we sure the valves were adjusted right? What procedure did you use?

If you have no vacuum leaks, then you might have a tight rocker


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## kevin1727 (Aug 4, 2021)

armyadarkness said:


> Are we sure the valves were adjusted right? What procedure did you use?


At #1 TDC, I adjusted all the rocker arm nuts by hand until I felt resistance on the push rod rotation. I could tell when the lifter spring was being compressed so I was careful to avoid doing that. Using a big wrench on the flywheel, I hand turned the engine approximately 90 degrees and repeated checking the push rods and nuts. Continued turning the engine 90 degrees at a time and checking for loose push rods until I completed two full engine rotations. Turned each nut 1/2 turn to preload the lifters and installed poly lock set screws and tightened. Turned each nut 1/16 to 1/8 turn to securely lock the nuts down.


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## armyadarkness (Dec 7, 2020)

Im thinking you may have a few tight valves. 

I know youre anxious to be done with this mess, but your vacuum should be higher than it is (IMO).

The issue with adjusting the way you did is if the lifters bleed down while doing it, you could be tricked into thinking that you have yet to achieve preload, when in fact, you already have.

It took me a very long time to learn this lesson, the HARD WAY!

Could I talk you into trying to pop the valve covers and checking them again with the engine running and a vacuum gauge hooked up?


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## kevin1727 (Aug 4, 2021)

armyadarkness said:


> Im thinking you may have a few tight valves.
> 
> I know youre anxious to be done with this mess, but your vacuum should be higher than it is (IMO).
> 
> ...


The lifters were probably all bled down because I did the adjustment on a cold engine. I could see that by pressing on the push rods to compress the lifter springs. 

I'll try starting with the valve covers off but if oil is flying, I'm stopping. 

What's the procedure if oil is not flying?


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## Baaad65 (Aug 29, 2019)

kevin1727 said:


> The lifters were probably all bled down because I did the adjustment on a cold engine. I could see that by pressing on the push rods to compress the lifter springs.
> 
> I'll try starting with the valve covers off but if oil is flying, I'm stopping.
> 
> What's the procedure if oil is not flying?


I just made cardboard shields about 4" high that tucked in the head up against the springs and wrapped up the sides, you're not revving the motor hardly at all. I didn't have any mess and leave one cover on while you do the other one.


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## kevin1727 (Aug 4, 2021)

Baaad65 said:


> I just made cardboard shields about 4" high that tucked in the head up against the springs and wrapped up the sides, you're not revving the motor hardly at all. I didn't have any mess and leave one cover on while you do the other one.


Okay, NOT splashing any oil at all. I can put rags above the plugs to catch any drips.

I'm guessing this is the procedure:
Back out the poly lock screws.
Adjust each rocker arm nut out until the rocker starts tapping then tighten 1/2 turn and lock it down with the set screw.

Right?


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## armyadarkness (Dec 7, 2020)

kevin1727 said:


> The lifters were probably all bled down because I did the adjustment on a cold engine. I could see that by pressing on the push rods to compress the lifter springs.
> 
> I'll try starting with the valve covers off but if oil is flying, I'm stopping.
> 
> What's the procedure if oil is not flying?


Unless your builder incorporated some restrictor, oil could be flying, but it's worth it.

Make some card board shields and do one side at a time. Whatever mess there is will be a laughing matter, once your tune is right!

If you hook up a vac gauge and loosen them one at a time while its warm and running, then adjust them, youll actually see the vac increasing and decreasing, based on your technique.


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## armyadarkness (Dec 7, 2020)

kevin1727 said:


> Okay, NOT splashing any oil at all. I can put rags above the plugs to catch any drips.
> 
> I'm guessing this is the procedure:
> Back out the poly lock screws.
> ...


Yes. Loosen one at a time, when it begins to clatter, snug it and lock it. 

When I did mine, my vac went from 12 to 18!


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## Baaad65 (Aug 29, 2019)

kevin1727 said:


> Okay, NOT splashing any oil at all. I can put rags above the plugs to catch any drips.
> 
> I'm guessing this is the procedure:
> Back out the poly lock screws.
> ...


September 20, 2022


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## Baaad65 (Aug 29, 2019)

armyadarkness said:


> Unless your builder incorporated some restrictor, oil WILL BE FLYING!
> 
> Make some card board shields and do one side at a time. Whatever mess there is will be a laughing matter, once your tune is right!
> 
> If you hook up a vac gauge and loosen them one at a time while its warm and running, then adjust them, youll actually see the vac increasing and decreasing, based on your technique.


Well idk how yours is but mine didn't have oil flying even revving it to 1000rpms....see video 👍


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## armyadarkness (Dec 7, 2020)

You might have oil restrictors, my friend. Butler built your engine and they're certainly aware of the issue, over oiling the top end. You may have special lifters or push rods.


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## armyadarkness (Dec 7, 2020)

Baaad65 said:


> Well idk how yours is but mine didn't have oil flying even revving it to 1000rpms....see video 👍


I have oil restrictors


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## kevin1727 (Aug 4, 2021)

armyadarkness said:


> Yes. Loosen one at a time, when it begins to clatter, snug it and lock it.
> 
> When I did mine, my vac went from 12 to 18!


Is 1/2 turn preload okay? I have read anywhere from 1/4 to 2 turns depending on stud thread pitch. These are 7/16-20 so one full turn is .050". Plus I turn almost 1/8 turn after tightening the set screws.


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## armyadarkness (Dec 7, 2020)

FYI, a half turn past zero lash is commonly used, but it's equally acceptable to only do 1/4 turn.


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## armyadarkness (Dec 7, 2020)

kevin1727 said:


> Is 1/2 turn preload okay? I have read anywhere from 1/4 to 2 turns depending on stud thread pitch. These are 7/16-20 so one full turn is .050". Plus I turn almost 1/8 turn after tightening the set screws.


I was answering that as you typed... For the record, I only use 1/4


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## kevin1727 (Aug 4, 2021)

armyadarkness said:


> I was answering that as you typed... For the record, I only use 1/4


Okay, I'll check back in a while with the results! Wish me luck.


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## Baaad65 (Aug 29, 2019)

armyadarkness said:


> You might have oil restrictors, my friend. Butler built your engine and they're certainly aware of the issue, over oiling the top end. You may have special lifters or push rods.
> [/QUOTE Idk maybe but neither of the descriptions on Butler's site say they are oil restricting.


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## armyadarkness (Dec 7, 2020)

As I mentioned, Butler would be intimately aware of this... They wouldnt mention on a build sheet that they installed oil restrictors, they would list part numbers for the lifters and push rods that they used.

For example, they dont list cam specs on a build sheet, just what cam was used.

You would have to go look up part numbers to find out if they had restrictor characteristics.

READ THIS from start to finish




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Loading…






butlerperformance.com


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## armyadarkness (Dec 7, 2020)




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## kevin1727 (Aug 4, 2021)

armyadarkness said:


> I was answering that as you typed... For the record, I only use 1/4


I must have done okay the first time because every one of them start clattering when I loosened them 1/2 turn. 
I tried 1/4 turn preload but there was still a slight noise on a few of them so I went with 1/2 turn. 
Vacuum is the same as before.


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## armyadarkness (Dec 7, 2020)

Then Im baffled. That vacuum sounds super low for that cam.


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## armyadarkness (Dec 7, 2020)

Did you get a new cap and rotor yet?


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## kevin1727 (Aug 4, 2021)

armyadarkness said:


> Did you get a new cap and rotor yet?


No. They are okay except that the square post on the rotor is now round but otherwise it's okay. 
I don't remember if I mentioned that before but I remounted the rotor correctly and then moved all the plugs wires around 180 degrees to match.


----------



## kevin1727 (Aug 4, 2021)

20220920 135934 x264


Adjusting rocker arm nuts




youtube.com


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## armyadarkness (Dec 7, 2020)

kevin1727 said:


> No. They are okay except that the square post on the rotor is now round but otherwise it's okay.
> I don't remember if I mentioned that before but I remounted the rotor correctly and then moved all the plugs wires around 180 degrees to match.


I know you corrected it, and maybe Im just being paranoid, but when gapping spark plugs; stock is .035", which is 1/32 of an inch, and a performance gap is .050, which is less than 1/16 of an inch.

What Im getting at is that the difference between those two is only 15 thousandths of an inch! 

If you ran that cap with the rotor misaligned, it couldve easily damaged it beyond what you'd want, but not enough to keep it from running. I know you said it looked okay. I hope so.

When do you expect to get the jet kit?

Hopefully Jim will chime in with his opinion of your vacuum, later this evening


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## kevin1727 (Aug 4, 2021)

armyadarkness said:


> I know you corrected it, and maybe Im just being paranoid, but when gapping spark plugs; stock is .035", which is 1/32 of an inch, and a performance gap is .050, which is less than 1/16 of an inch.
> 
> What Im getting at is that the difference between those two is only 15 thousandths of an inch!
> 
> ...


The rotor was not misaligned. It was seated completely and I've looked at the rotor and cap very closely. I cannot see any issue. I checked it very carefully. The plugs are all gapped at .045. 
Plan to get the jet kit this Friday when I take the car over to the windshield guy to check out why the brand new windshield is cloudy. Yes, a lot of other issues.


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## Jared (Apr 19, 2013)

I have my plugs gapped to 0.045" too. Also running a HEI distributer. 0.035 would be correct for a points distributer, too small of a gap for a HEI.


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## Baaad65 (Aug 29, 2019)

I have mine at 0.034 with a MSD R2R, I thought I read something from PJ and in the Tuning to Win book that it is a good gap?


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## Baaad65 (Aug 29, 2019)

Here's what I found on the FBO site, he wrote the Tuning to Win book.


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## Jared (Apr 19, 2013)

Baaad65 said:


> I have mine at 0.034 with a MSD R2R, I thought I read something from PJ and in the Tuning to Win book that it is a good gap?


It probably is for the distributer you're using. HEI needs a bigger gap.


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## PontiacJim (Dec 29, 2012)

kevin1727 said:


> The numbers I posted on #277 above are after the push rods were fixed and rockers adjusted. About 11" at idle of 850rpm. I read elsewhere that with the valve lift and 4 degrees retarded cam I'm running, that number may be typical.
> 
> 
> 
> ...



Explain to me why you are running the cam 4 degrees retarded??


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## kevin1727 (Aug 4, 2021)

PontiacJim said:


> Explain to me why you are running the cam 4 degrees retarded??


I do not know. That is the engine builder. I don't remember if my builder told me or if I read it that it helps power at higher end?


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## kevin1727 (Aug 4, 2021)

PontiacJim said:


> Explain to me why you are running the cam 4 degrees retarded??


I texted my builder. He says it allows for more spark advance.
Can you tell from the cam spec I posted if it's machined that way or if it's installed that way?


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## Jim K (Nov 17, 2020)

PontiacJim said:


> Explain to me why you are running the cam 4 degrees retarded??


Glad you asked that question Jim.. I was pondering a response to ask that question.. I know mine (From Crower) is 4 Deg advanced ground and was told Pontiacs respond well with a little advance grind on the cams.


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## Jared (Apr 19, 2013)

Jim K said:


> Glad you asked that question Jim.. I was pondering a response to ask that question.. I know mine (From Crower) is 4 Deg advanced ground and was told Pontiacs respond well with a little advance grind on the cams.





kevin1727 said:


> I texted my builder. He says it allows for more spark advance.
> Can you tell from the cam spec I posted if it's machined that way or if it's installed that way?


I'm pretty sure that the paperwork that comes with the Comp Cams also indicate a 4 degree advance on their Pontiac grinds. That's what I remember from when I put my engine together. Based on communication from the builder, it sounds like the cam was installed this way. Depending on the timing set, you can select a bunch of options for advancing or retarding the valve timing. Now the question is was it set just 4 degrees retarded from the straight up position or 8 degrees off from straight up to make it 4 degrees retarded. I'm not an expert on this but this could be the reason for lower than expected vacuum.


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## Jared (Apr 19, 2013)

This could also be why the timing was set more advanced than what is normal for a Pontiac.


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## Baaad65 (Aug 29, 2019)

Jared said:


> It probably is for the distributer you're using. HEI needs a bigger gap.


More than the MSD with a reluctor wheel? I thought HEI was the same as all the electronic ignitions.


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## PontiacJim (Dec 29, 2012)

kevin1727 said:


> I do not know. That is the engine builder. I don't remember if my builder told me or if I read it that it helps power at higher end?


Probably a bad move on the advice from your builder. This changes the cam's valve events. Retarding the cam "softens" the bottom RPM's if you have a car with a lot of traction/tire spinning. It does supposedly give you more top end power at higher RPM's, but do you plan to spin the engine to 6K? Did you plan on racing the car or cruising?

Not sure what your compression ratio is, but if stock, the 110 LSA Comp Cams may have not been a good selection as the 110 LSA has a tendency to build more cylinder pressure - which works good on low compression engines.

Is your torque converter stock? You may need more stall to help you out, something like a 2,500 stall where it can put the cam/engine higher up into its power band and pull much better.

The Comp Cams has a ground in 4-degree advance. The advance improves low end power and throttle response. Advancing the cam will close the intake sooner, which builds lower rpm cylinder pressure. Retarding does the opposite. The 110 LSA cams typically build more cylinder pressure at the lower RPM's Maybe that was the thinking?

The cam card says to install the ICL @ 106 degrees which means the cam is 4-degrees advanced. If you retarded the cam 4-degrees then the cam's ICL would be 110 degrees or what is called "straight up."

So changing the valve events may be part of the "soggy" bottom end and lower vacuum readings.

*Cam retard:

Retarding the camshaft (the intake & exhaust valves both open & close later) has these general effects:

» cranking pressure is reduced 
» tendency to knock at low speed is reduced 
» low speed power is reduced 
» idle speed is probably reduced 
» idle smoothness is increased 
» peak torque may be reduced, but at higher RPM 
» peak power may be increased 
» intake valve to piston clearance increased 
» exhaust valve to piston clearance reduced 
» traction (for 1/4 mile racing) is increased 
» overlap duration is not affected, but engine vacuum may change 
» idle and low speed exhaust note is softer, due to both later intake closing and exhaust opening *


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## PontiacJim (Dec 29, 2012)

kevin1727 said:


> I texted my builder. He says it allows for more spark advance.
> Can you tell from the cam spec I posted if it's machined that way or if it's installed that way?


MORE BS - where does this all come from????? Argh!

Ignition timing ONLY has to do with when the spark plug lights. The distributor may be driven by the cam gear BUT, the distributor rotates freely and can be rotated in any position to set the timing wherever you want, regardless of whether the cam is advanced, retarded or straight-up. Just because they share the same word of "timing" doesn't mean they are referring to the same MEANING of what "timing" is.





__





How does cam timing affect ignition timing?


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Does Cam Timing Affect Ignition Timing?


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## Baaad65 (Aug 29, 2019)

Soooo to fix this does he just have to remove the timing cover and timing chain gear and adjust the cam? And I know that's a big "just".


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## kevin1727 (Aug 4, 2021)

PontiacJim said:


> MORE BS - where does this all come from????? Argh!
> 
> Ignition timing ONLY has to do with when the spark plug lights. The distributor may be driven by the cam gear BUT, the distributor rotates freely and can be rotated in any position to set the timing wherever you want, regardless of whether the cam is advanced, retarded or straight-up. Just because they share the same word of "timing" doesn't mean they are referring to the same MEANING of what "timing" is.
> 
> ...


I know exactly what you're saying. My builder is just saying that whether the cam design is advanced or retarded, then the spark advance may need to be set differently for best performance.


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## kevin1727 (Aug 4, 2021)

Jared said:


> I'm pretty sure that the paperwork that comes with the Comp Cams also indicate a 4 degree advance on their Pontiac grinds. That's what I remember from when I put my engine together. Based on communication from the builder, it sounds like the cam was installed this way. Depending on the timing set, you can select a bunch of options for advancing or retarding the valve timing. Now the question is was it set just 4 degrees retarded from the straight up position or 8 degrees off from straight up to make it 4 degrees retarded. I'm not an expert on this but this could be the reason for lower than expected vacuum.


My paperwork doesn't show 4 degrees. It only says specs are for the cam installed at 106 Intake Center Line. 
Not sure how that correlates to 4 degrees.








Xtreme Energy 224/230 Hydraulic Flat Cam for Pontiac 265-455


Xtreme Energy 224/230 Hydraulic Flat Tappet Cam for Pontiac 265-455. Good for street machines. 2000+ stall. Slightly rough idle.




www.compcams.com


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## kevin1727 (Aug 4, 2021)

Baaad65 said:


> Soooo to fix this does he just have to remove the timing cover and timing chain gear and adjust the cam? And I know that's a big "just".


LOL. 
Yeah, what about all that s**t in the way?


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## kevin1727 (Aug 4, 2021)

Jared said:


> This could also be why the timing was set more advanced than what is normal for a Pontiac.


My guy says my timing light must be bad. He says the timing was set to 11 degrees base. I haven't touched it but I'm measuring between 16 and 17 on my Actron CP7529.


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## kevin1727 (Aug 4, 2021)

Jared said:


> It probably is for the distributer you're using. HEI needs a bigger gap.


Isn't it the coil that determines the energy?


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## Baaad65 (Aug 29, 2019)

kevin1727 said:


> LOL.
> Yeah, what about all that s**t in the way?


Well if you don't have to take the cam out which I don't think you do then it's "just" the fan, pulleys and cover plus two hoses. Think you could leave the radiator in but that's not a big deal if you want more room.


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## kevin1727 (Aug 4, 2021)

I'm almost back to the point where this whole thread started. Frustrated that I can't find the problem and stuck between my lack of knowledge and tools and taking it back to the builder who I don't want to deal with. 

Although with everyone's help here I am able to do a whole lot more than when I started. And together we found and fixed a MAJOR problem. 

I would have never thought I'd be adjusting the valve lash with the engine running and valve covers off. Not to mention adjusting the toe-in, installing a fuel regulator, and replacing the turn signal switch. 

You all have been GREAT. I've also learned a lot from searching and reading the forums too so it hasn't just been this one huge thread teaching me. 

I just need to keep plugging away. Several car shows coming up. Maybe I can find resources there too. Maybe even someone who will see what it's doing and know right off what's wrong.


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## armyadarkness (Dec 7, 2020)

PontiacJim said:


> Explain to me why you are running the cam 4 degrees retarded??


When I read it, I was afraid to ask. I assumed it was a Pro-Tip


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## RMTZ67 (Mar 12, 2011)

kevin1727 said:


> I'm almost back to the point where this whole thread started. Frustrated that I can't find the problem and stuck between my lack of knowledge and tools and taking it back to the builder who I don't want to deal with.
> 
> Although with everyone's help here I am able to do a whole lot more than when I started. And together we found and fixed a MAJOR problem.
> 
> ...


If you can install a turn signal switch, you can do anything lol.


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## Baaad65 (Aug 29, 2019)

This IS a great forum and I've learned so much and still learn something almost everyday. So do you think the builder would fix the cam problem seeing all this information or is he going to say I didn't install the cam wrong I just did it a different way? You could take him for a ride and ask "do think this is right" a car with that motor can't make it up a hill. And all this time he thought the carb was the problem...doesn't sound like it now. Maybe it's time for a little break like was suggested before but don't give up, these smart guys here got your back...I'm just not one of them....yet 👍


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## armyadarkness (Dec 7, 2020)

kevin1727 said:


> LOL.
> Yeah, what about all that s**t in the way?


At the end of the day, it's not a lengthy job, but lets not go there yet.


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## armyadarkness (Dec 7, 2020)

kevin1727 said:


> My guy says my timing light must be bad. He says the timing was set to 11 degrees base. I haven't touched it but I'm measuring between 16 and 17 on my Actron CP7529.


If you have an MSD box, dont expect a digital timing light to cooperate!


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## armyadarkness (Dec 7, 2020)

I think the next step is to clarify with the builder that the cam was installed correctly, dot to dot, and that his statement "the cam is retarded" is merely him referring to what he believed was built into the cam.


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## RMTZ67 (Mar 12, 2011)

armyadarkness said:


> If you have an MSD box, dont expect a digital timing light to cooperate!


What happened to the days when you set your base timing with a taillight harness and bulb?


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## kevin1727 (Aug 4, 2021)

PontiacJim said:


> Explain to me why you are running the cam 4 degrees retarded??


After a whole bunch of texts with my builder I'm convinced he didn't make the cam decision nor install it. It was all done by his engine builder.


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## kevin1727 (Aug 4, 2021)

armyadarkness said:


> I think the next step is to clarify with the builder that the cam was installed correctly, dot to dot, and that his statement "the cam is retarded" is merely him referring to what he believed was built into the cam.


I think you are right. 
I will have to get the contact information of the engine builder. I don't think my builder really knows any more than the cam part number from CompCams.


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## armyadarkness (Dec 7, 2020)

Baaad65 said:


> So do you think the builder would fix the cam problem


We havent determined that theres a cam problem. There's a lot of information flying around here and it's easy to go down a deep rabbit hole. As I said early on, lets pull out the splinter before we decide to amputate.


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## RMTZ67 (Mar 12, 2011)

So would using a piston stop to find true TDC shed any light on his cam position?


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## armyadarkness (Dec 7, 2020)

kevin1727 said:


> I think you are right.
> I will have to get the contact information of the engine builder. I don't think my builder really knows any more than the cam part number from CompCams.


As Jim mentioned, cam manufacturers build timing into the cam and then state that on the card/ instructions. This is easy to confuse and easily misunderstood. 

There are three guys on this forum right now, trying to run dizzys on the street, without vac advance cans, and chasing their tales because their cars dont run right... This is definitely a case of where the internet is not our friend.

This is not the time for old wives tales and hearsay, it's time to systematically check each part of the equation until the error is revealed, That will determine the repair.

Picking up a wrench without first having all of the appropriate data, test results, and planning, is just asking for a lot of big problems.


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## armyadarkness (Dec 7, 2020)

RMTZ67 said:


> So would using a piston stop to find true TDC shed any light on his cam position?


I suppose that's a round about way. The piston at TDC should put the timing mark at zero. The cam couldve been degreed? It's hard to imagine that anyone with the skill to degree a cam, would install rockers without verifying clearance.


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## RMTZ67 (Mar 12, 2011)

armyadarkness said:


> I suppose that's a round about way. The piston at TDC should put the timing mark at zero. The cam couldve been degreed? It's hard to imagine that anyone with the skill to degree a cam, would install rockers without verifying clearance.


Not sure what Kevins reference for timing is but, when I bought a new balancer from butler the timing mark was not close to tdc. They offered to send me a new one but I settled for the piston stop and timing tape,,,,the rest is history.


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## PontiacJim (Dec 29, 2012)

kevin1727 said:


> My paperwork doesn't show 4 degrees. It only says specs are for the cam installed at 106 Intake Center Line.
> Not sure how that correlates to 4 degrees.
> 
> 
> ...



4-degrees is typically built right into the cam by the cam grinder. So the spec used when dialing in the cam is the 106 degrees Intake Center Line (ICL).

To determine if a camshaft has ground-in advance, subtract the Intake Centerline from the Lobe Separation Angle. 
For example, a camshaft has an intake centerline of 106° and an LSA of 110°.

*110° - 106° = 4° ground-in advance*

Not trying to discourage you or throw in the towel, just trying to sort through some of the issues that are not making sense. Seems like a number of inaccurate motorhead locker room chatter that is not based on facts, but buddies getting together at the track and passing along bad info and no one knowing any better to call them out on it.

Not a big deal IF you had to go in and dial in the cam, BUT, I would try and speak with the actual engine builder and see if he has any notes or remembers what he set the cam at. He may also have a reason as to why he retarded the cam if he indeed did retard it. But at this point, I would not assume the cam was retarded and it may just be a wrong assumption altogether. It would have to be for a specific reason that a builder would retard a cam rather than install it per the cam card.

So find this out if you can and then report back and we can go from there. If everything is on the up and up, then we can go back with the carb adjustments and/or timing to see if we can get the engine more responsive and crisp.


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## PontiacJim (Dec 29, 2012)

RMTZ67 said:


> What happened to the days when you set your base timing with a taillight harness and bulb?


That was pre-internet and when we were poor speed freaks! How did we ever live without cell phones? LOL


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## Jared (Apr 19, 2013)

kevin1727 said:


> Isn't it the coil that determines the energy?


Yes. Figure that the original coil used would have less power going to it than your HEI does. I am no expert at this but did a lot of reading on this before I set mine up. Everything I could find indicated a larger spark gap for HEI. I found reference to gaps as small as 0.040 and as large as 0.048. I split the difference and called it a day. Car seems to like it. I have not played around tweaking the gap to look for very minor improvements.

This all being said, I will not speak for folks running other forms of electronic ignition. Their needs could be different. I was gearing up to run HEI so that's what I focused my research on.


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## armyadarkness (Dec 7, 2020)

PontiacJim said:


> 4-degrees is typically built right into the cam by the cam grinder. So the spec used when dialing in the cam is the 106 degrees Intake Center Line (ICL).


Exactly my thought, and I suspect that this is simply being misunderstood.


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## armyadarkness (Dec 7, 2020)

PontiacJim said:


> Not trying to discourage you or throw in the towel, just trying to sort through some of the issues that are not making sense. Seems like a number of inaccurate motorhead locker room chatter that is not based on facts, but buddies getting together at the track and passing along bad info and no one knowing any better to call them out on it.


This is what I was referring to yesterday. Learning anything requires practical, scientific, theoretical, and working knowledge. No one of those things is going to bring you full circle, because you need them all.

It's one thing to read something on the internet, it's another to understand it, and it's another to be able to conduct it.

When I picked my cam, I spent days on the internet, studying famous Pontiac cams, then I spent day on the internet and Butlers website researching, then I spent weeks going back and forth with @PontiacJim about them.

But then I had to sort through all of it and use the advice and options, to determine what was best for my needs. I didnt arbitrarily pick what someone else recommended... but if I didnt spend so much time learning first, then I wouldve had no choice but to do so.

Let me tell you, I still dont understand 75% of it, but Im wise enough to only take on what I can handle. You have to have a plan, a method, and persistence, and learn from your mistakes. If you do, you'll achieve your goals, and if you don't, it wont just be a GTO that you suck at.


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## kevin1727 (Aug 4, 2021)

I've got to take a break for a while to spend time with the other half and try to get more information from engine builder.
Going to get the front end aligned and the windshield checked out in the meantime.

My plans for the hesitation:
lube the accelerator pump (need to know what kind of lube).
measure total timing and maybe adjust spark timing.
try lighter springs for carb jets.


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## armyadarkness (Dec 7, 2020)

Yes... with vacuum that low, oem springs for that Eddy would lift the needles out of the seats VERY/ TOO quickly


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## Baaad65 (Aug 29, 2019)

kevin1727 said:


> I've got to take a break for a while to spend time with the other half and try to get more information from engine builder.
> Going to get the front end aligned and the windshield checked out in the meantime.
> 
> My plans for the hesitation:
> ...


Don't know if you bought a new timing light but I have an Innova digital light and really like it. And yes keep the other half happy, that's way more important than cam shaft problems


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## Philski (Aug 17, 2019)

kevin1727 said:


> I've got to take a break for a while to spend time with the other half and try to get more information from engine builder.
> Going to get the front end aligned and the windshield checked out in the meantime.
> 
> My plans for the hesitation:
> ...


 Hory smokes! I started reading this with Frustrated With Builder. I couldn't put it down until I got here... I should be out in my barn welding and grinding on my own project! I've seen all the excellent advice and tips by knowledgeable people on here. So glad to see you get your car corrected to this point. One thing bothers me though. I may have missed it, but has anyone asked where you're hooking up the vacuum advance hose from the distributor ? It needs to be hooked up to the port above the throttle plates to work correctly. I may be stating the obvious here, but I'm following the basic rules of troubleshooting, "never assume anything".😗


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## kevin1727 (Aug 4, 2021)

Philski said:


> Hory smokes! I started reading this with Frustrated With Builder. I couldn't put it down until I got here... I should be out in my barn welding and grinding on my own project! I've seen all the excellent advice and tips by knowledgeable people on here. So glad to see you get your car corrected to this point. One thing bothers me though. I may have missed it, but has anyone asked where you're hooking up the vacuum advance hose from the distributor ? It needs to be hooked up to the port above the throttle plates to work correctly. I may be stating the obvious here, but I'm following the basic rules of troubleshooting, "never assume anything".😗


Glad it's been a page turner. It was for me too.

I tried it ported and not-ported, and it doesn't make any difference. Seems to me it should make some difference but I don't notice it.


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## armyadarkness (Dec 7, 2020)

Like I said... easy to mask some issues with others.


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## Jared (Apr 19, 2013)

kevin1727 said:


> *I've got to take a break for a while to spend time with the other half* and try to get more information from engine builder.
> Going to get the front end aligned and the windshield checked out in the meantime.
> 
> My plans for the hesitation:
> ...


Highlighted. The most important part of these projects! You gotta keep your better half happy. You know, for the next time you set off all the CO monitors in the house while breaking in a new cam shaft in the driveway with the garage door open and she's inside on a zoom work meeting. I "know a guy" that happened to and the wife thought it was funny.

All joking aside. I want to add that I respect the way you're going about this. A lot of other guys would be hopping mad, ready to throw in the towel, or both. Keep at it. You'll get this dialed in and running exactly how you want it. Like I said a bunch of posts ago, mine wasn't running that f=great when I first got it back on the road either. I slowly worked at it until I got it running the way I wanted it to. It took me a few weeks and ~500 miles to do it.


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## Baaad65 (Aug 29, 2019)

Jared said:


> Highlighted. The most important part of these projects! You gotta keep your better half happy. You know, for the next time you set off all the CO monitors in the house while breaking in a new cam shaft in the driveway with the garage door open and she's inside on a zoom work meeting. I "know a guy" that happened to and the wife thought it was funny.
> 
> All joking aside. I want to add that I respect the way you're going about this. A lot of other guys would be hopping mad, ready to throw in the towel, or both. Keep at it. You'll get this dialed in and running exactly how you want it. Like I said a bunch of posts ago, mine wasn't running that f=great when I first got it back on the road either. I slowly worked at it until I got it running the way I wanted it to. It took me a few weeks and ~500 miles to do it.


I think I remember that guy, wasn't he on the right coast  He was that guy I think ready to set fire to it and I bet there's some screwdrivers in the wall too but everyone here jumped to the rescue to keep him from selling it.....I hope he doesn't regret us one day


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## Baaad65 (Aug 29, 2019)

Philski said:


> Hory smokes! I started reading this with Frustrated With Builder. I couldn't put it down until I got here... I should be out in my barn welding and grinding on my own project! I've seen all the excellent advice and tips by knowledgeable people on here. So glad to see you get your car corrected to this point. One thing bothers me though. I may have missed it, but has anyone asked where you're hooking up the vacuum advance hose from the distributor ? It needs to be hooked up to the port above the throttle plates to work correctly. I may be stating the obvious here, but I'm following the basic rules of troubleshooting, "never assume anything".😗


Are you trying to start a civil war with ported or non ported vacuum


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## geeteeohguy (Feb 2, 2008)

Most Pontiacs were set up originally with manifold vacuum to the advance on the distributor. This gave a cooler running engine at low and idle speeds and good advance at cruise speeds where the intake manifold vacuum is still high. I have always run manifold vacuum on my first-gen GTO's, as set-up from the factory. Some engines seem to prefer ported vacuum, though.


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## Jared (Apr 19, 2013)

Baaad65 said:


> I think I remember that guy, wasn't he on the right coast  He was that guy I think ready to set fire to it and I bet there's some screwdrivers in the wall too but everyone here jumped to the rescue to keep him from selling it.....I hope he doesn't regret us one day


I think he was on the right coast now that you mention it. I seem to remember it more of a near panic attack when he thought he wiped out a new cam because it wouldn't fire because "that guy" had the wires 180 degrees off. No screw drivers were harmed during the process. My, err I mean that guy's, kid's vocabulary will never be the same though.


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## PontiacJim (Dec 29, 2012)

geeteeohguy said:


> Most Pontiacs were set up originally with manifold vacuum to the advance on the distributor. This gave a cooler running engine at low and idle speeds and good advance at cruise speeds where the intake manifold vacuum is still high. I have always run manifold vacuum on my first-gen GTO's, as set-up from the factory. Some engines seem to prefer ported vacuum, though.


The ported was a by-product as emission standards were being pushed hard on these cars.


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## Philski (Aug 17, 2019)

Baaad65 said:


> Are you trying to start a civil war with ported or non ported vacuum


Nah.🥸 I just think that if you're running a non-adjustable vacuum advance, there's no since in having full advance at idle.


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## armyadarkness (Dec 7, 2020)

Jared said:


> Highlighted. The most important part of these projects! You gotta keep your better half happy. You know, for the next time you set off all the CO monitors in the house while breaking in a new cam shaft in the driveway with the garage door open and she's inside on a zoom work meeting. I "know a guy" that happened to and the wife thought it was funny.
> 
> All joking aside. I want to add that I respect the way you're going about this. A lot of other guys would be hopping mad, ready to throw in the towel, or both. Keep at it. You'll get this dialed in and running exactly how you want it. Like I said a bunch of posts ago, mine wasn't running that f=great when I first got it back on the road either. I slowly worked at it until I got it running the way I wanted it to. It took me a few weeks and ~500 miles to do it.


It took me a year and a half and several thousand miles to get it worked out


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## armyadarkness (Dec 7, 2020)

geeteeohguy said:


> Most Pontiacs were set up originally with manifold vacuum to the advance on the distributor. This gave a cooler running engine at low and idle speeds and good advance at cruise speeds where the intake manifold vacuum is still high. I have always run manifold vacuum on my first-gen GTO's, as set-up from the factory. Some engines seem to prefer ported vacuum, though.


I run mine off the intake and sometimes at Cruise my vacuum gets up in the high twenties


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## Baaad65 (Aug 29, 2019)

armyadarkness said:


> I run mine off the intake and sometimes at Cruise my vacuum gets up in the high twenties


Me 2, and like I've learned here you only want 10° that's where I locked mine at.


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## ponchonlefty (8 mo ago)

Baaad65 said:


> Soooo to fix this does he just have to remove the timing cover and timing chain gear and adjust the cam? And I know that's a big "just".


if the cam is not dialed in right then yes.


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## Baaad65 (Aug 29, 2019)

I'm not derailing this exciting mystery novel but since kev is taking a break and it was brought up I thought I would share this from Don Gould from FBO Systems who wrote "Tuning To Win". I've talked to him once and have the book and set up my curve to his advice, lot of good info at his site 4secondsflat.com especially spark plug reading. Not saying this is gospel but it works for me and seems to make good sense. I would recommend reading the tech articles and such on the site and get the book....and he has a sense of humor with a tell it like it is quality. Now back to our regularly scheduled drama 😉 Ported vacuum source, Constant manifold vacuum source explained, the difference between ported and manifold vacuum.


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## armyadarkness (Dec 7, 2020)

As we see in here daily, no two cars are alike. This is why the full understanding of the process, is much more important than the process itself.

If you just give advice that you heard or advice that worked for you, it could easily work against another member... but if you understand the science and theory behind what youre doing, then you can give the person the skills that they need to resolve thier own issue. That's the "teach a man to fish" principle.

And I would say that this forum is very dedicated to that purpose.

If someone asked me what to set their vacuum advance at, I wouldnt say "10", I would ask about all of their other settings and readings, and then explain why it mattered and what they should expect. In fact, typically when a member posts that they just want the answer and not the explanation, I dont even answer. It's like a trap... I prefer to walk around it.

Every one of us could solve any problem that there ever was, if the single answer to it was written on the wall. Unfortunately, the answer is never that obvious... and that's when scientific understanding comes in. By the process of elimination, you conduct tests until you find the error. However, the more popular method of problem solving, seems to be "throwing shit at the wall and seeing what sticks". The issue there is that you have to then wade through a pile of shit to get your answer.

As informative as this thread has been to those following, it'll be useless to anyone who finds it next year, because it's very unlikely that they'll read through 20 pages of confusion to find the answer.

The day Kevin posted this thread, I gave him my number. A few pages into the thread, he called me and I told him to pull the dizzy cap and valve covers. That night he discovered a misinstalled rotor, and the next morning he discovered the rocker arms had fallen off... So 5 minutes worth of science was the equivalent of 2 weeks of guessing.

As I said before, I know everyone is here to help, but the best way to help isnt always to give the answers. As jared mentioned, Im quite impressed that Kevin rolled up his sleeves and faced this problem head on. With that determination, success is guaranteed.


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## geeteeohguy (Feb 2, 2008)

Spark plug 'reading' is not what it once was with leaded gas. You can still tell if it's rich or lean or is burning oil, but not much else. The advent of AFR gauges is a true godsend to those who don't have decades to get a 'feel' for adjusting fuel mixtures. Same goes for dyno tuning in general. You can realize a very sharp state of tune with the right equipment even if you are not a 'pro'. As a former 'pro', repairing vehicles on flat-rate salary, I had to be accurate and timely to make money. I learned to fix any known faulty parts or components FIRST and establish a vehicle baseline and go from there. Still works today. One step at a time.


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## Philski (Aug 17, 2019)

armyadarkness said:


> As we see in here daily, no two cars are alike. This is why the full understanding of the process, is much more important than the process itself.
> 
> If you just give advice that you heard or advice that worked for you, it could easily work against another member... but if you understand the science and theory behind what youre doing, then you can give the person the skills that they need to resolve thier own issue. That's the "teach a man to fish" principle.
> 
> ...


OK. I yield to experience and knowledge. Sometimes I speak when I should just listen. Sometimes, what I think I know isn't all I need to know, that much I know. 😜 I never had any high performance or muscle cars when I was growing up or raising a family. I've always repaired my own cars and done extensive work on them, but I never had any performance cars until I got my first '86 Corvette in '98. So, anyhoo, when I finally do get to the day when I get ready to put the old 400 back in mine, I may be asking questions about building it


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## armyadarkness (Dec 7, 2020)

Lol. Experience and knowledge are rarely used to describe me... But I do advocate for a unified understanding of mechanicals, vs just repeating what you hear.

There are things that I know plenty about... cams, timing, and Pontiac tricks were not included.

I was very fortunate that I was able to come to this forum, as a blank slate, with extensive scientific and mechanical skills, eager to learn and with open ears. The corvette forums would not have been so generous as this community. 

At the end of the day, it's not what you know that wins the race, it's your determination to the goal. Im glad that so many people came out in this thread to help.


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## kevin1727 (Aug 4, 2021)

OK, I have a blind builder. And two calibration kits with lots of mismatched parts.

Jets in the carb were stock but had two different size metering rods. LOL 

Instead of stock calibration, I am going 1 step leaner on the primary. Stock jets on secondary.

Lubed the accelerator pump.

Cleaned dirt out of a couple of jets on the primary.

The springs in the kit look like the coloring has come off most of them. I measured and sorted the springs by wire diameter and overall length. I can only determine any color on the ones that appear purple (top) and orange (2nd). The top three are .017 wire diameter and the bottom one .015 which I guess is the weakest.
Spring ratings are supposed to be:

Silver 8"
Pink 7"
Orange 5"
Yellow 4"
Blue 3"

Any idea the ratings of these pictured?


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## kevin1727 (Aug 4, 2021)

Stock spec jets are .110 and stock rods are .075 x .047
1 step leaner are .107 jets and .073 x .037 rods
I calculated the cross sections. The leaner setup is a smaller cross section only at vacuum when the rods are down. It is actually larger at low vacuum when the rods are up on the small steps.


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## Baaad65 (Aug 29, 2019)

Well I guess that explains your carb problems 🤦‍♂️ sorry no help I'm a Holley/Quickfuel guy.


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## kevin1727 (Aug 4, 2021)

Baaad65 said:


> Well I guess that explains your carb problems 🤦‍♂️ sorry no help I'm a Holley/Quickfuel guy.


Proof will be in the test but I agree that these seemed like significant findings.


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## PontiacJim (Dec 29, 2012)

Baaad65 said:


> I'm not derailing this exciting mystery novel but since kev is taking a break and it was brought up I thought I would share this from Don Gould from FBO Systems who wrote "Tuning To Win". I've talked to him once and have the book and set up my curve to his advice, lot of good info at his site 4secondsflat.com especially spark plug reading. Not saying this is gospel but it works for me and seems to make good sense. I would recommend reading the tech articles and such on the site and get the book....and he has a sense of humor with a tell it like it is quality. Now back to our regularly scheduled drama 😉 Ported vacuum source, Constant manifold vacuum source explained, the difference between ported and manifold vacuum.


Hmmm.

*FBO:* The Vacuum Can needs to be adjusted to pull enough timing in the motor to allow it to burn the today's fuel and limiters installed to set the part throttle cruise timing numbers so they don't pull the timing too high and cause a lean miss at cruise, it's a delicate balancing act to get it all correct.

*PJ:* Not neccesarily a correct concept. You can adjust your Intial Timing at the balancer to pull more timing than stock and then adjust/limit the vacuum advance total by purchasing a vacuum can with limited advance OR use a stop. Or, you can keep the factory Initial timing and keep the factory can advance OR a combination thereof depending on your engine build. What is not written is you want to limit the Total Mechancial Advance *PLUS* the Vacuum Advance to around 50 degrees combined while cruising on part/light throttle or off the throttle coasting. A lean miss could be possible (usually your engine will "surge" if over advanced by the vacuum advance). if the timing is "over advanced". This is why we often suggest knowing what all your timing parameters are - Initial with no vacuum advance, Total advance at "X" RPM without vacuum advance, and then how much additional advance the vacuum can provides PLUS at what Hg the vacuum advance begins to function.

*FBO*: "*Ported vacuum:* when the ported starts to do it's job and advances the the timing to the total stroke of the vacuum can arm, usually 12-18* (without Limiters) so now have your total of 34* PLUS the stroke of the Canister arm of say 16* _net result=50* of total timing under hard acceleration _and your motor WILL "Detonate"."

*PJ:* Engine vacuum drops to near 0 under hard acceleration and drops back down to 34 degrees as set-up by your Total mechanical advance - so that statement is incorrect.

Oh man, this paragraph is a mess:

*FBO:* "*Now to Constant: * At idle/part throttle cruise you have high vacuum, the carb is nearly closed causing a restriction which creates the high vacuum level. Under this light load condition and lean AF ratios the motor needs more timing to burn the fuel (Lean Mixtures take Longer to Burn than rich mixtures) - *PJ: TRUE. FBO:* so you need more timing at idle and cruise to burn the fuel correctly and completely. *PJ: TRUE.* *FBO:* When you stomp the throttle you have NO manifold Vacuum so you have NO vacuum timing and at NO time under high load will it ever advance more than the mechanical "All In" numbers. *PJ: TRUE. FBO: *Stop pointing your finger at the carb for rich idle and top end lean conditions. - *PJ: Huh? *So a rich idle can be eliminated by simply advancing your timing? And a top end lean condition can also be cured by adjusting my timing? Very cool, I will remember this when one of our members states his carb is running rich at idle or leaning out on the top end - it's not a carb adjustment of the idle circuits or the need for larger jets, its your timing. *FBO:* *It's In Your Distributor Tuning! *If your Buddy tells you to hook your Hot Rod distributor to Ported Vacuum, find a new friend because that guys advice is going to blow your crankshaft through the oil pan.* PJ: What?* Blow my crankshaft through the oil pan? Maybe that's why there are no cars from the mid-1970's and up that used Ported Vacuum to reduce emissions - they all blew their crankshaft through the oil pans. * FBO:* Same goes for the guy who say's to disconnect it, they obviously have no idea of how it works or what it does or why we use it. *PJ:* Go looking for a vacuum advance can/distributor on a race car. Guess Pontiac did not know how one worked either when they installed a dual point distributor with no vacuum advance on the 1956 Pontiac 285HP engine or 421 SD engines, the Ford HP engines 352-390-406-427-'67 Shelby 428 and 289 hipos all had no vacuum advance, the Corvette 283 and 409/425 HP had no vacuum advance, and the list of factory cars goes on. A vaccum advance can *is always recommended* on this Forum because it can aide in a cooler running engine, and better gas mileage, BUT, you can run without one and take your chances.

*FBO:* "we have Mopar and GM vacuum cans that will read 7" of vacuum. most stock or aftermarket Vac cans will only read down to about 15", the odd one (1 out of 100) will read to 12"

*PJ:* I can buy GM vacuum cans for the lower vacuum engines on RockAuto, so not as exclusive as a supplier as they think they are. Modified engines with more cam that generate less than 15” Hg. of vacuum at idle need a vacuum advance can that’s fully-deployed at least 1”, preferably 2” of vacuum less than idle vacuum level so idle advance is solid and stable. The B28/Echlin #VC-1810/AC-Delco #D1312C/Autozone DV1810 advance can provides 15 degrees of advance, but is fully-deployed at only 8” of vacuum. Most stock vacuum advance cans aren’t fully-deployed until they see about 15” Hg. Those cans don’t work very well on a modified engine having less than 15” Hg.and produce a rough idle, the stock vacuum can will “dither” in and out in response to the rapidly-changing manifold vacuum of a lumpy cam and constantly varying the amount of vacuum advance, which in turn can create an unstable idle.


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## PontiacJim (Dec 29, 2012)

Philski said:


> OK. I yield to experience and knowledge. Sometimes I speak when I should just listen. Sometimes, what I think I know isn't all I need to know, that much I know. 😜 I never had any high performance or muscle cars when I was growing up or raising a family. I've always repaired my own cars and done extensive work on them, but I never had any performance cars until I got my first '86 Corvette in '98. So, anyhoo, when I finally do get to the day when I get ready to put the old 400 back in mine, I may be asking questions about building it


The more I research and learn, the more I realize that I didn't really know as much as I thought - so with this perspective, I have learned that there are no absolutes and no Pontiac experts who know it all. I am open to listening without judgment as to whether it is fact or fiction or something in between unless I KNOW. To KNOW about something is to have no more questions because they have all been answered - proving fact or fiction. If someone cannot answer all my questions, then they don't KNOW either.


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## Baaad65 (Aug 29, 2019)

PontiacJim said:


> Hmmm.
> 
> *FBO:* The Vacuum Can needs to be adjusted to pull enough timing in the motor to allow it to burn the today's fuel and limiters installed to set the part throttle cruise timing numbers so they don't pull the timing too high and cause a lean miss at cruise, it's a delicate balancing act to get it all correct.
> 
> ...


 The first thing I said is that it's not the gospel that everyone should follow but the guy has been tuning cars for a long time and I have his cell number if you want to talk to him about it. I may be dumb and gullible but it just seems to make sense, I had my curve like most but now I have it like he recommended, a 14° bushing with 22° on the balancer and my vac can limited to 10° (which I learned here) and it runs cooler and faster than my wife to a half off sale at DSW ! so that's all I have to go by, no track testing or dyno testing. He gives advice to our kind of motors not just race motors, and a few of the members have his book. I just copied his article on timing because it was brought up and thought I would share what is working for me and I know there are a thousand different opinions on this that's all. Now maybe I looked at things differently than you did on some of his theories idk, like having a more advanced timing at idle when those of us with carburetors that are dribbling fuel into the intake and
getting a pooling effect especially with a dual plane like a lot of us have when there's no air velocity. Secondly the crankshaft through the oil pan comment probably is meaning from detonation and yes when you stomp the throttle I know the vac can cuts out but it takes a second so maybe he was a little over the top with that. Third, why didn't those motors you described have a vacuum advance, maybe in '56 they didn't know much about it but certainly by the 60's they did, were they race motors..no so idk why they didn't use it heck Butler didn't have one on my motor when I got it because they said it was a wild card. They certainly knew about adjustable cans or limiters although MSD didn't have one for the R2R dist but I got a proto type limiter from them. And I agree that rich and lean conditions are mostly carb related but don't you think what he is saying is that advanced timing at idle when cylinder pressures are low will burn off more fuel and aren't detrimental but when timing is advanced to much at high rpms results in detonation because of a lean condition? I'm not trying to say he's the be all end all of tuners I just love learning from all these discussions 👍


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## kevin1727 (Aug 4, 2021)

I think I'm missing the blue spring. The spring with the most widely spread coils is the yellow one so that would be the dark colored spring in my kit. 
I've got about 10-1/2" of vacuum at 850 rpm idle , and about 9" vacuum in gear so I'm looking at either the orange or yellow spring, right?
EDIT: forgot the photo


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## Jim K (Nov 17, 2020)

Kevin, I would go with the yellow. If you have something more radical than a factory (milder) cam then your vacuum signal might not be rock steady. You can try the orange springs, but I would check them by opening the metering rod/spring cover with the engine idling and see if there is any "bounce" of the metering rod while using the orange springs. That can throw you off when trying to tune it.


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## kevin1727 (Aug 4, 2021)

Jim K said:


> Kevin, I would go with the yellow. If you have something more radical than a factory (milder) cam then your vacuum signal might not be rock steady. You can try the orange springs, but I would check them by opening the metering rod/spring cover with the engine idling and see if there is any "bounce" of the metering rod while using the orange springs. That can throw you off when trying to tune it.


Thanks. That's what I'm thinking too. I tried the orange springs. The rods stayed down pretty well but jumped up with a little throttle tickle.


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## Jim K (Nov 17, 2020)

kevin1727 said:


> Thanks. That's what I'm thinking too. I tried the orange springs. The rods stayed down pretty well but jumped up with a little throttle tickle.


You may at first experience a leaner condition on initial acceleration using the yellow springs but most often times, using the richest hole position on the power piston rod, or larger diameter squirt nozzel(s) off the power piston can help that. This is where the "fine tuning" comes in for your application.


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## PontiacJim (Dec 29, 2012)

Baaad65 said:


> The first thing I said is that it's not the gospel that everyone should follow but the guy has been tuning cars for a long time and I have his cell number if you want to talk to him about it. I may be dumb and gullible but it just seems to make sense, I had my curve like most but now I have it like he recommended, a 14° bushing with 22° on the balancer and my vac can limited to 10° (which I learned here) and it runs cooler and faster than my wife to a half off sale at DSW ! so that's all I have to go by, no track testing or dyno testing. He gives advice to our kind of motors not just race motors, and a few of the members have his book. I just copied his article on timing because it was brought up and thought I would share what is working for me and I know there are a thousand different opinions on this that's all. Now maybe I looked at things differently than you did on some of his theories idk, like having a more advanced timing at idle when those of us with carburetors that are dribbling fuel into the intake and
> getting a pooling effect especially with a dual plane like a lot of us have when there's no air velocity. Secondly the crankshaft through the oil pan comment probably is meaning from detonation and yes when you stomp the throttle I know the vac can cuts out but it takes a second so maybe he was a little over the top with that. Third, why didn't those motors you described have a vacuum advance, maybe in '56 they didn't know much about it but certainly by the 60's they did, were they race motors..no so idk why they didn't use it heck Butler didn't have one on my motor when I got it because they said it was a wild card. They certainly knew about adjustable cans or limiters although MSD didn't have one for the R2R dist but I got a proto type limiter from them. And I agree that rich and lean conditions are mostly carb related but don't you think what he is saying is that advanced timing at idle when cylinder pressures are low will burn off more fuel and aren't detrimental but when timing is advanced to much at high rpms results in detonation because of a lean condition? I'm not trying to say he's the be all end all of tuners I just love learning from all these discussions 👍


Vacuum Advance has been around long time. My '48 International has vacuum advance - it moves the distributor body within the engine block, not the points plate inside the distributor. Many HP engines did not use vacuum advance as they were aimed more for all out racing, even though they were sold to the public. Pontiac knew what they were doing - th typical non-285HP engine used a single point distributor with vacuum advance. FBO may be a fine outfit and know what they are doing, BUT, for someone who is unfamiliar with distrib. timing or its purpose, then the things I pointed out are somewhat in question and/or not so accurately explained. I did not like how they inferred "if your buddy says" that your buddy was an idiot or didn't know what he was talking about. There are times, even on a Hotrod, where ported vacuum may work better. There are times when no vacuum advance can work better - it all depends on the engine build and its use/application, and that was never spoken. A rich or lean carb condition could be the problem needing solving and not considering it and seemingly implying it is a distrib issue is not 100% correct. Again, as you have seen here, there is a process of checks/tests to go through to get to the point were you can start looking at the distrib. as the cause or fix of your engine fuel issues - and this should have been mentioned. And making it sound like you want to use them to get your "correct" vacuum can because you can't, is a bit misleading.

The article is a bit skewed and is certainly a marketing piece to steer your to them for your timing set-up, or parts/pieces. But my point overall is from the perspective of that guy/enthusiast who wants to learn/understand the timing features of his set-up and how to best adjust it for his particular engine build. This write-up lacks a bit of accuracy. Maybe the FBO test/tune guy did not write this article and someone else did - which can often be the case. So the inaccuracies are not on the part of FBO, but whomever wrote it up. But then the unknowing newbee or enthusiast read it and takes it to heart and then passes this info to another and then we have mis-information and we are right where FBO talks of when "if your buddy........".

So not a slam at FBO per say, as I don't know them. I do have their FBO ignition box on my '73 Fury and it works great and does exactly as they claimed. My critique is of the article which lends itself to implicate FBO as maybe not being as knowledgeable as I know they are. They are well spoken of and used in the Mopar community with me being one of those proponents for their products.

Like many things, auto or general, write-ups and explanations can found on the internet 100 times over by 100 people who want to post "that" information either to be helpful or get their name on the net. But when certain companies/people who sell a product, offer a service, or are looked to for advice, they need to be as thorough and accurate as they can be so the reader is fully informed with as many of the facts/steps/info as possible to promote a successful outcome - and sometimes that can require a lengthy break down or long article to fully explain or get that info across to the reader, and many internet articles don't do that or are simply thrown together by an author who gets paid to post an article because that's how they make money - and I have read many of these by web authors who make their income this way and don't necessarily know much about the subject.

*If you can't dazzle them with brilliance, baffle them with bullshit.*


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## Baaad65 (Aug 29, 2019)

PontiacJim said:


> Vacuum Advance has been around long time. My '48 International has vacuum advance - it moves the distributor body within the engine block, not the points plate inside the distributor. Many HP engines did not use vacuum advance as they were aimed more for all out racing, even though they were sold to the public. Pontiac knew what they were doing - th typical non-285HP engine used a single point distributor with vacuum advance. FBO may be a fine outfit and know what they are doing, BUT, for someone who is unfamiliar with distrib. timing or its purpose, then the things I pointed out are somewhat in question and/or not so accurately explained. I did not like how they inferred "if your buddy says" that your buddy was an idiot or didn't know what he was talking about. There are times, even on a Hotrod, where ported vacuum may work better. There are times when no vacuum advance can work better - it all depends on the engine build and its use/application, and that was never spoken. A rich or lean carb condition could be the problem needing solving and not considering it and seemingly implying it is a distrib issue is not 100% correct. Again, as you have seen here, there is a process of checks/tests to go through to get to the point were you can start looking at the distrib. as the cause or fix of your engine fuel issues - and this should have been mentioned. And making it sound like you want to use them to get your "correct" vacuum can because you can't, is a bit misleading.
> 
> The article is a bit skewed and is certainly a marketing piece to steer your to them for your timing set-up, or parts/pieces. But my point overall is from the perspective of that guy/enthusiast who wants to learn/understand the timing features of his set-up and how to best adjust it for his particular engine build. This write-up lacks a bit of accuracy. Maybe the FBO test/tune guy did not write this article and someone else did - which can often be the case. So the inaccuracies are not on the part of FBO, but whomever wrote it up. But then the unknowing newbee or enthusiast read it and takes it to heart and then passes this info to another and then we have mis-information and we are right where FBO talks of when "if your buddy........".
> 
> ...


I get it and they do seem to cater to the Mopars, also the book does have quite a few typos too. I do like his sense of humor about fuel filters that I posted a while back. Like I said it's working for me...your results may vary 😉


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## armyadarkness (Dec 7, 2020)

kevin1727 said:


> Stock spec jets are .110 and stock rods are .075 x .047
> 1 step leaner are .107 jets and .073 x .037 rods
> I calculated the cross sections. The leaner setup is a smaller cross section only at vacuum when the rods are down. It is actually larger at low vacuum when the rods are up on the small steps.


Remember, the kit doesnt address each setting... you can make whatever combo that you like. So if you like, just go one size BIGGER on the needles, which will lean you out.

What Im trying to say is that the needles and primaries arent necessarily in sets.

As for the springs, your vacuum is supper low, so just put the lightest springs in and try it. Remember, they're not going to richen or lean, they just determine "when" you get the primaries. This is why it's important to understand what each part does and when.

I will say that at first glance, Eddy's instructions are not so great, and they vary among several different manuals.


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## armyadarkness (Dec 7, 2020)

kevin1727 said:


> I think I'm missing the blue spring. The spring with the most widely spread coils is the yellow one so that would be the dark colored spring in my kit.
> I've got about 10-1/2" of vacuum at 850 rpm idle , and about 9" vacuum in gear so I'm looking at either the orange or yellow spring, right?
> EDIT: forgot the photo
> 
> View attachment 157679


Spring rating should be half your vacuum. So you want no more than a 6... but again, if you go heavier, it's not going to kill you, it's just going to bring on the primaries before their time.


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## armyadarkness (Dec 7, 2020)

Jim K said:


> You may at first experience a leaner condition on initial acceleration using the yellow springs but most often times, using the richest hole position on the power piston rod, or larger diameter squirt nozzel(s) off the power piston can help that. This is where the "fine tuning" comes in for your application.


I wouldnt go heavier than yellow for his vacuum


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## kevin1727 (Aug 4, 2021)

I've tried the lightest springs but no improvement, maybe even a little worse. I'm going in the other direction next. 
I also tried increasing the vacuum advance a couple degrees and backing off the initial timing the same amount. No difference. With such a low idle vacuum, the vacuum advance isn't doing much at that point. 
None of the changes have raised the vacuum. I'm still at 10-1-/2 to 11" depending on the idle speed.


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## armyadarkness (Dec 7, 2020)

kevin1727 said:


> I've tried the lightest springs but no improvement, maybe even a little worse.


Which likely means you're too lean! 

As Ive said... this can be deceiving because some setting can mask the real culprit!

Soft springs will keep the needles in the seats longer, so you might think that getting them out "faster" is the fix, when in fact, your needles are too big... which will also show as lean.

The problem is, you'll never fix lean needles by changing springs.

I have to say... any cam that's radical enough to knock your vacuum down to 10hg, is gonna want gas! I personally think you're tuning in the wrong direction.

My 400 with 15hg of vacuum has an 800 CFM Eddy, which Ive richened up at least 5 settings from base, and Im still on the lean side!


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## armyadarkness (Dec 7, 2020)

kevin1727 said:


> I've tried the lightest springs but no improvement, maybe even a little worse. I'm going in the other direction next.
> I also tried increasing the vacuum advance a couple degrees and backing off the initial timing the same amount. No difference. With such a low idle vacuum, the vacuum advance isn't doing much at that point.
> None of the changes have raised the vacuum. I'm still at 10-1-/2 to 11" depending on the idle speed.


Have you tried to bump up base timing?


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## kevin1727 (Aug 4, 2021)

armyadarkness said:


> Remember, the kit doesnt address each setting... you can make whatever combo that you like. So if you like, just go one size BIGGER on the needles, which will lean you out.
> 
> What Im trying to say is that the needles and primaries arent necessarily in sets.
> ............


I went by the numbered suggestions in the tuning instructions. I know if I just change the needles, I could be making large differences. The numbered suggestions are small changes. The step I made is richer with the needles up and leaner with the needles down. 

From my experience with this builder I'm trusting the base carb settings more. It's more likely my builder did something wrong. As I found with the two different size needles he had installed. 

The carb is supposedly new. The accelerator plunger is orange which I read is from an older design and the new one is blue. There are supposedly a couple other changes that were made by Edelbrock that are incorporated if I buy a $20 upgrade kit. I'm going to try the heavy springs and if that doesn't help, I may get that kit. 

I can't do too much test driving until I get the car aligned Oct 3rd. It is chewing up the front tires since my builder fixed the front suspension springs and took out the dropped spindles. It was toed in a LOT, and I adjusted the best I could with a tape measure.


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## kevin1727 (Aug 4, 2021)

armyadarkness said:


> Which likely means you're too lean!
> 
> As Ive said... this can be deceiving because some setting can mask the real culprit!
> 
> ...


Yes, I'm suspecting too lean.

The change I made gives me a slightly richer mix with the needles up (power mode) and slightly leaner with the needles down (cruise mode).

I put stiffer springs in but haven't driven it yet. Found this note in the tuning instructions:
"If your vehicle has a mid-throttle driveability problem that is encountered as the throttle is gradually opened, but then goes away upon further opening, it may be possible to eliminate the lean spot by using a stronger Step-Up Spring "


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## kevin1727 (Aug 4, 2021)

armyadarkness said:


> Have you tried to bump up base timing?


I lowered the base timing to 14 and increased the vacuum advance up two degrees. At low vacuum idle, I'm only seeing the 14 degrees. I'm making changes that seem to be more "average" or towards stock.


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## armyadarkness (Dec 7, 2020)

kevin1727 said:


> I'm making changes that seem to be more "average" or towards stock.


Once you added a cam that was only going to give you 10hg of vacuum, a stock tune was taken from your options.

You're now in the "advance as much as possible, without detonation", aisle. 

If you want that thing to run smooth and cool at idle, you cant go skimping on the timing.

Personally, I'd disconnect the vac can and plug the line, then turn the dizzy for a nice smooth idle... readjust the idle speed screw, reset the mixtures, and see how it runs. Dont back off until you either get detonation or starter kick back.

Yes, you can go on the soft side of timing, but you may then have trouble with cooling and/ or octane.


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## kevin1727 (Aug 4, 2021)

armyadarkness said:


> Once you added a cam that was only going to give you 10hg of vacuum, a stock tune was taken from your options.
> 
> You're now in the "advance as much as possible, without detonation", aisle.
> 
> ...


Following your suggestion, I can get up to about 28 degrees advance before the engine grunts on cranking. I lowered to 22 and cranking is okay, but just a little grunt. The more I advanced the timing, the more I had to lower the idle screw to maintain 850rpm.
That does bring the vacuum up a little to a solid 11", maybe 11-1/2".
I never found a "smooth" idle point.

EDIT:
At 22 degrees advance, the base + mechanical timing tops out at 40 degrees. Is that too high?


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## kevin1727 (Aug 4, 2021)

I took a test drive. The hesitation is almost gone. It makes the transition from idle to power without spinning gravel and also chugs up my hill okay.

Here's the idle video:


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## armyadarkness (Dec 7, 2020)

kevin1727 said:


> At 22 degrees advance, the base + mechanical timing tops out at 40 degrees. Is that too high?


Mine is almost 40, as well. As long as it's not pinging, then don't sweat it. 

This is why the dizzy's that I recommend work so well. You can keep a base timing that works, and then change the centrifugal to suit the engine as well... With an HEI, you set your initial to be what the engine loves, but then if the total is too high, you have to back off on the initial.

This forces you to make compromises. 

But 11 or 12 initial should be good.


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## kevin1727 (Aug 4, 2021)

armyadarkness said:


> ....
> But 11 or 12 initial should be good.


But I'm at 22 base. So I'm only getting 18 mechanical. It hits 40 degrees at about 2,400 rpm and doesn't go higher when I rev to 3,000.
Difficult to switch between rpm and advance on my timing light while trying to hold the throttle steady and the light on the mark. That fan blade is a nasty steel meat slicer.

These numbers match what my builder measured. About base 14 and total 32 that I could see over his shoulder.


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## geeteeohguy (Feb 2, 2008)

These cars with a stock distributor and stock timing curve will run 48-50 degrees advanced at low rpm light cruise. If too lean, they will detonate, even under very light load. BTDT, many times.


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## armyadarkness (Dec 7, 2020)

kevin1727 said:


> But I'm at 22 base. So I'm only getting 18 mechanical. It hits 40 degrees at about 2,400 rpm and doesn't go higher when I rev to 3,000.
> Difficult to switch between rpm and advance on my timing light while trying to hold the throttle steady and the light on the mark. That fan blade is a nasty steel meat slicer.


You need to stop considering the vacuum advance in your base timing


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## armyadarkness (Dec 7, 2020)

Your HEI probably has 20 mechanical advance, so with an initial timing of 14, your total would be 34 degrees.

When you said it was 40, did you read that with a timing light, or are you adding initial + vacuum + mechanical, to deduce it?


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## armyadarkness (Dec 7, 2020)

If you wish to find out how much total advance you have, disconnect the vacuum advance, pull the dizzy cap, take the springs off the weights, start the car and read it with a dial back.

Never include the vacuum in your total timing.


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## kevin1727 (Aug 4, 2021)

armyadarkness said:


> You need to stop considering the vacuum advance in your base timing


vacuum is not connected per your recommendation.


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## armyadarkness (Dec 7, 2020)

kevin1727 said:


> vacuum is not connected per your recommendation.


Ok... but how did you determine that you're getting 40, total?


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## kevin1727 (Aug 4, 2021)

armyadarkness said:


> Your HEI probably has 20 mechanical advance, so with an initial timing of 14, your total would be 34 degrees.
> 
> When you said it was 40, did you read that with a timing light, or are you adding initial + vacuum + mechanical, to deduce it?


I'm reading that with a dial back timing light, Actron CP7529. Vacuum line to the dizzy is disconnected and plugged at the carb. I checked the advance with the timing light set at 32 degrees advance and the mark was on 8 at high rpm. I reset the light to 40 degrees and the mark was at zero. The timing mark advances to zero about 2,400 (edited) 2,800 rpm and stay there as I rev higher. 

Of course, everything is probably plus or minus a degree or two. The mark is not dead steady and bounces a little.


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## Jared (Apr 19, 2013)

kevin1727 said:


> I took a test drive. The hesitation is almost gone. It makes the transition from idle to power without spinning gravel and also chugs up my hill okay.
> 
> Here's the idle video:


This sounds a heck of a lot better than the one you posted a couple weeks ago. Nice work on this Kevin!


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## kevin1727 (Aug 4, 2021)

From what I'm reading elsewhere, it appears I shouldn't top out on timing so soon. Some things I'm reading say the curve should max out at 3,500 or so.
I also read that my engine will explode if set to 45 degrees all-in. I REALLY don't want to risk any engine damage.

I don't need the fastest car on the road. I'd like to be able to screech the tires starting off sometimes, but it doesn't need to do that at 45mph. A nice rumble idle would be nice.

I just want a car that runs well and doesn't embarrass me by stalling when I'm trying to leave a car show.


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## kevin1727 (Aug 4, 2021)

Jared said:


> This sounds a heck of a lot better than the one you posted a couple weeks ago. Nice work on this Kevin!


Yes, it's night and day difference. Still got some tweaking to do. I just hope I can do it. Don't trust my builder anymore.


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## kevin1727 (Aug 4, 2021)

Here's the "like new" 600cfm he wanted to install for me. Yeah, that's dust, mildew, and dirt all over it.


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## kevin1727 (Aug 4, 2021)

I checked timing a few more times again. I'm getting more brave with the engine screaming over 3,000 rpm and me leaning over it. LOL
All-in timing peaks closer to 2,800 than 2,400.


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## armyadarkness (Dec 7, 2020)

kevin1727 said:


> From what I'm reading elsewhere, it appears I shouldn't top out on timing so soon.


Your cam typically dictates when you want the all in. Your cam makes its max power in a specific range, that's ideally what you should consider to be your target.


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## armyadarkness (Dec 7, 2020)

kevin1727 said:


> From what I'm reading elsewhere, it appears I shouldn't top out on timing so soon. Some things I'm reading say the curve should max out at 3,500 or so.
> I also read that my engine will explode if set to 45 degrees all-in. I REALLY don't want to risk any engine damage.
> 
> I don't need the fastest car on the road. I'd like to be able to screech the tires starting off sometimes, but it doesn't need to do that at 45mph. A nice rumble idle would be nice.
> ...


That's what I said yesterday. But, as you might have read in this forum, these Pontiacs tend to run hot and the cams give them rough idles, so dont back off too much or you might struggle with temperatures and idling.


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## armyadarkness (Dec 7, 2020)

kevin1727 said:


> I checked timing a few more times again. I'm getting more brave with the engine screaming over 3,000 rpm and me leaning over it. LOL
> All-in timing peaks closer to 2,800 than 2,400.


No one is ever going to recomend that you ever go over 40 degrees of all in timing. Keep in mind that your balancer may not be completely accurate either. So if it's running how you want it now, with no detonation, maybe back it off a degree and then start tuning the carb.


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## armyadarkness (Dec 7, 2020)

kevin1727 said:


> Here's the "like new" 600cfm he wanted to install for me. Yeah, that's dust, mildew, and dirt all over it.
> 
> View attachment 157704


That carb is at least 30 years old.


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## armyadarkness (Dec 7, 2020)

kevin1727 said:


> Yes, it's night and day difference. Still got some tweaking to do. I just hope I can do it. Don't trust my builder anymore.


You obviously have it under control now. Try and tune it out through the carb, and then down the road, maybe youll swap the cam and build a custom dizzy, with your new skills!


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## kevin1727 (Aug 4, 2021)

I pulled the distributor and rotated it to put #1 at the desired position. It started at a 45 angle and then went CW with the timing adjustment. 

Firewall at the top in this photo looking down through the gap between the hood and cowl.

Also got the air can in a better place. I tried to get it parallel with the firewall but the gears don't allow it. The can rotates into the head when the timing goes to 22. 

Had to move the oil pump slot to get the distributor where I wanted. Rearranged all the plug wires. Now I don't have such a mess as before. This wire set fits better with the cap like this.

First time I ever pulled a distributor out. I learned that the car will not start without timing advance. I might have even had it retarded a little at first because I saw a flash at the carburetor once.


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## kevin1727 (Aug 4, 2021)

I've been adjusting the timing and idle mixture. The car really seems to like at least 22 degrees of base timing. 

At 22 degrees the rpms are increasing and I am able to reduce the idle speed screw and still have increased vacuum.
Then when I connect the vacuum advance I can reduce the idle screw a little more and I'm now at 12" vacuum. That's the highest vacuum I've been able to get so far. 

I'm still at 40 all-in timing (without the vacuum advance).

I could go higher on the base timing but I'm going to run it at 22 a while.


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## armyadarkness (Dec 7, 2020)

kevin1727 said:


> I've been adjusting the timing and idle mixture. The car really seems to like at least 22 degrees of base timing.
> 
> At 22 degrees the rpms are increasing and I am able to reduce the idle speed screw and still have increased vacuum.
> Then when I connect the vacuum advance I can reduce the idle screw a little more and I'm now at 12" vacuum. That's the highest vacuum I've been able to get so far.
> ...


This is a bit confusing. 

The other day, I told you that you should stop including vacuum advance timing in your base number... because I assumed that you were doing that. However, this reads like you're not.

*"At 22 degrees the rpms are increasing and I am able to reduce the idle speed screw and still have increased vacuum.Then when I connect the vacuum advance I can reduce the idle screw a little more and I'm now at 12" vacuum"*

So, is your base at 22 without the can?


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## kevin1727 (Aug 4, 2021)

armyadarkness said:


> This is a bit confusing.
> 
> The other day, I told you that you should stop including vacuum advance timing in your base number... because I assumed that you were doing that. However, this reads like you're not.
> 
> ...


Yes, base is 22 without the can.

None of my timing numbers include vacuum advance. I'm only using base plus centrifugal. At idle there is no noticeable centrifugal advance. 

After I set my timing and idle speed, I then connect the vacuum advance. I have to readjust the idle speed because the idle speed goes up when I connect the vacuum advance line. My vacuum also ends up a little higher at the end even though I reset the idle speed. I read that is because my throttle plates are now closed a little further.

I'm going to see if I can adjust the can to get 4 more degrees of vacuum advance at idle so I can set base timing to 18 and reduce the chance of hard cranking. That should also put my all-in timing (without vacuum advance) to 36 degrees.

Goal is to get a higher idle speed vacuum. 
By increasing the can advance the rpm will increase. Then I will get more throttle plate closing when I adjust for a correct idle screw position. Then the vacuum will increase. There may be few iterations but there should be a point where I'm running a decent idle speed vacuum above 12". Maybe even closer to 15".


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## armyadarkness (Dec 7, 2020)

kevin1727 said:


> Yes, base is 22 without the can.
> 
> None of my timing numbers include vacuum advance. I'm only using base plus centrifugal. At idle there is no noticeable centrifugal advance.
> 
> ...


Got it!

I have to say, I thought I had the highest base timing on this entire forum, but yours takes the cake. Normal is 12-14. Mine is 18.

I can't believe that you cam is so big that it requires 22, and/ or that 22 isnt giving you issues. How is it running now?


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## goat671 (Apr 13, 2019)

Is it possible the distributor is one tooth out? Just wondering that seems alot of initial timing, but hey what ever is working.


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## Baaad65 (Aug 29, 2019)

armyadarkness said:


> Got it!
> 
> I have to say, I thought I had the highest base timing on this entire forum, but yours takes the cake. Normal is 12-14. Mine is 18.
> 
> I can't believe that you cam is so big that it requires 22, and/ or that 22 isnt giving you issues. How is it running now?


Mines at 22° because I have a 14° bushing and 10° in my can, runs like a beast and no starting issues...I don’t have a choke and don't need one started the other day without even touching the pedal when it was 55 degrees out.


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## kevin1727 (Aug 4, 2021)

armyadarkness said:


> Got it!
> 
> I have to say, I thought I had the highest base timing on this entire forum, but yours takes the cake. Normal is 12-14. Mine is 18.
> 
> I can't believe that you cam is so big that it requires 22, and/ or that 22 isnt giving you issues. How is it running now?


It runs okay at that setting. I'm hearing a tiny bit of grunt when I first crank it. Once it starts and is warm and idling, it is fine. Only a little rough. Takes a while to warm up and get a stable idle, otherwise I'm revving the engine to keep it going for the first minute or two. The choke and high idle setting must need some adjustment. It won't idle high. Maybe idle screws, choke plate, or something??

I haven't noticed any pinging on the road. It's got much more power now that's it's running on 8 cylinders instead of 6 but seems to me it should still be a little stronger for that size engine. 

Of course, don't forget my builder. Is it possible that he installed the balancer wheel 10 degrees advanced? I can see from the mounting bolts it could be 90 degrees out but that would be obvious??


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## kevin1727 (Aug 4, 2021)

goat671 said:


> Is it possible the distributor is one tooth out? Just wondering that seems alot of initial timing, but hey what ever is working.


No, I adjusted timing after the distributor reinstallation.


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## armyadarkness (Dec 7, 2020)

goat671 said:


> Is it possible the distributor is one tooth out? Just wondering that seems alot of initial timing, but hey what ever is working.


My concern is that Ive seen people put dizzys in a tooth off, retarded, and then they think they're advancing the timing, which they are, but from cylinder number #2, instead of #1


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## armyadarkness (Dec 7, 2020)

Baaad65 said:


> Mines at 22° because I have a 14° bushing and 10° in my can, runs like a beast and no starting issues...I don’t have a choke and don't need one started the other day without even touching the pedal when it was 55 degrees out.












If it could trailer itself to the car shows, I would be calling Guinness


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## armyadarkness (Dec 7, 2020)

kevin1727 said:


> It runs okay at that setting. I'm hearing a tiny bit of grunt when I first crank it. Once it starts and is warm and idling, it is fine. Only a little rough. Takes a while to warm up and get a stable idle, otherwise I'm revving the engine to keep it going for the first minute or two. The choke and high idle setting must need some adjustment. It won't idle high. Maybe idle screws, choke plate, or something??
> 
> I haven't noticed any pinging on the road. It's got much more power now that's it's running on 8 cylinders instead of 6 but seems to me it should still be a little stronger for that size engine.
> 
> Of course, don't forget my builder. Is it possible that he installed the balancer wheel 10 degrees advanced? I can see from the mounting bolts it could be 90 degrees out but that would be obvious??


As I mentioned, Ive seen where people dropped the dizzy in on cylinder #2, which a timing light shows as #1 being retarded, then they had to advance the Hell out of it to get it to run... Not that it's what you're dealing with, but you have had the dizzy out a few times, and admittedly are not experienced with that, and it would certainly explain why it wont start unless its advanced


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## armyadarkness (Dec 7, 2020)

kevin1727 said:


> No, I adjusted timing after the distributor reinstallation.


But it could be off a tooth.


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## armyadarkness (Dec 7, 2020)

kevin1727 said:


> I'm going to see if I can adjust the can to get 4 more degrees of vacuum advance at idle so I can set base timing to 18 and reduce the chance of hard cranking.


assuming the dizzy is in right, thats a good plan


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## armyadarkness (Dec 7, 2020)

kevin1727 said:


> The choke and high idle setting must need some adjustment. It won't idle high. Maybe idle screws, choke plate, or something??


Ive also seen many chokes set wrong... Eddys instructions for it are crap


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## Baaad65 (Aug 29, 2019)

armyadarkness said:


> View attachment 157793
> 
> 
> If it could trailer itself to the car shows, I would be calling Guinness
> [/QUOTE Ha ha, It's been on one trailer when it got delivered since I've had it and the next time will be to the track


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## kevin1727 (Aug 4, 2021)

armyadarkness said:


> But it could be off a tooth.


How could it be off a tooth? With #1 at TDC, the distributor can be inserted in any orientation. Wherever the rotor ends up is #1 plug wire. Then you rotate the distributor to get the timing.
I think that saying comes from people pulling the distributor and then reinserting without verifying the rotor is back in the same position and not resetting the timing.


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## kevin1727 (Aug 4, 2021)

WOOHOO!!
Happy dance and smiling face!!
🕺 🤸‍♂️ 

Set base timing at idle to 18 degrees (vacuum line disconnected and plugged at carb). 

Adjusted advance can screw all the way to get full vacuum advance at idle. I'm measuring 30 degrees advance with the vacuum advance line on, so vacuum advance is adding 12 degrees, which the engine likes. Tweaked the idle to 850 rpm.

I'm getting 13" of vacuum at 850 rpm idle!!

Re-tweaked the idle mixture screws.

Easy cranking startup when hot.

Took it out for a drive and the hesitation is GONE !!

I also stopped on the highway and left about 30 to 40 feet of rear tire on the road before it upshifted to 2nd.


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## armyadarkness (Dec 7, 2020)

Congrats. That's awesome bro


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## armyadarkness (Dec 7, 2020)

kevin1727 said:


> How could it be off a tooth? With #1 at TDC, the distributor can be inserted in any orientation. Wherever the rotor ends up is #1 plug wire. Then you rotate the distributor to get the timing.
> I think that saying comes from people pulling the distributor and then reinserting without verifying the rotor is back in the same position and not resetting the timing.


It's very easy to screw up dizzy installs... but Im not going there, since it doesnt seem an issue


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## Baaad65 (Aug 29, 2019)

kevin1727 said:


> WOOHOO!!
> Happy dance and smiling face!!
> 🕺 🤸‍♂️
> 
> ...


Nice! Isn't it satisfying when you fix things yourself after battling them and they turn out good, glad you stuck with it...now aren't you glad you didn't sell it? Congrats you deserve a few cold ones 🍻


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## RMTZ67 (Mar 12, 2011)

Maybe a piston stop is in order. Get True TDC then see where the rotor is pointing in reference to the # 1 wire. Shouldn't have too, but stranger things have happened here. I am sure your close or it wouldn't start/run.


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## kevin1727 (Aug 4, 2021)

RMTZ67 said:


> Maybe a piston stop is in order. Get True TDC then see where the rotor is pointing in reference to the # 1 wire. Shouldn't have too, but stranger things have happened here. I am sure your close or it wouldn't start/run.


I'm sure it's fine. The only issue could be if the timing mark is not on zero when the piston is TDC. 

I've read that the harmonic balancer can slip if the rubber insulator is rotted?? 
That's why I asked above if it could be installed a few degrees off. The ones I see online have a keyway so I'm thinking it can't be screwed up??


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## kevin1727 (Aug 4, 2021)

Baaad65 said:


> Nice! Isn't it satisfying when you fix things yourself after battling them and they turn out good, glad you stuck with it...now aren't you glad you didn't sell it? Congrats you deserve a few cold ones 🍻


I was so upset at the beginning. I was trusting my builder. I thought he knew what he was doing.
I knew something was wrong but had no idea how to find it. I've got so much money into this car and work on a garage to store it, so, total frustration. 

Only with y'alls' help here was I able to find the problems and make my builder own up to it.

Plus everyone's continued support, *especially Armyadarkness's phone support*, I've gained a huge amount of confidence and knowledge.

I'm smiling a lot.
Yep, time for an Oktoberfest beer.


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## armyadarkness (Dec 7, 2020)

kevin1727 said:


> I'm sure it's fine. The only issue could be if the timing mark is not on zero when the piston is TDC.
> 
> I've read that the harmonic balancer can slip if the rubber insulator is rotted??
> That's why I asked above if it could be installed a few degrees off. The ones I see online have a keyway so I'm thinking it can't be screwed up??


Balancer can only go on one way... accuracy is another topic. Yes, they can slip... I would say youre fine and leave well enough alone.

Some day, buy a new performance balancer, if you like.


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## armyadarkness (Dec 7, 2020)

kevin1727 said:


> especially Armyadarkness's phone support


Thank you for acknowledging. 

On top of the many hours a day that I spend here on the forum, I spend a LOT of time on the phone, every day, helping people here with their cars. It's a huge sacrifice, but I love helping people, and none more deserving than this GTO community. I will always do it, so long as the help is always appreciated.

Many people here have helped me, and paying it forward is what's right.


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## armyadarkness (Dec 7, 2020)

BTW... I often find myself helping several of you, even when you don't want the help! Im thrilled that Kevin took the advice quickly and acted on it. After 5 pages of guessing, a 5 minute phone call revealed both his dizzy and rocker issue. Sometimes you just need to be open minded... have some faith, and above all else patience!

The fact that Kevin got it under control, on his own, and now has the skill and experience, is priceless!

Always take the help!


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