# Timing



## Baaad65 (Aug 29, 2019)

Ok I got my MSD vacuum advance today that I talked about in the overheating thread, installed it and I left the intial at 16° then plug in the can and it's reading 29° so I'm assuming that's to much I remembered someone in the thread said to set initial at 10°, the can said it's good for about 10°. I didn't have time for a drive and I forgot to check total advance but before the can I thought that I had 45° @ 2500 rpm. Any advice would be much appreciated.


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## Baaad65 (Aug 29, 2019)

Here's something else I hope won't be a problem, when I went to use the snap ring pliers a piece of one of the eight reducters I guess they're called broke off and there was rust on both sides so it's been cracked for a while, the car runs fine so hopefully it won't affect anything. At least I got the piece before it fell off while things were rotating. I haven't called MSD yet but does anyone know if I can replace that pickup wheel or do I have to replace the distributor?


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## Baaad65 (Aug 29, 2019)

Here's another picture.


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## PontiacJim (Dec 29, 2012)

Baaad65 said:


> Ok I got my MSD vacuum advance today that I talked about in the overheating thread, installed it and I left the intial at 16° then plug in the can and it's reading 29° so I'm assuming that's to much I remembered someone in the thread said to set initial at 10°, the can said it's good for about 10°. I didn't have time for a drive and I forgot to check total advance but before the can I thought that I had 45° @ 2500 rpm. Any advice would be much appreciated.


Yep, too much Initial. 29-16=13. So the vacuum can gives you 13 degrees of advance.


You only want about 20-21 Initial. So, 21-13=8 Try 8 degrees with no can. Then connect the vacuum can and your Initial should jump to 21.


Disregard vacuum advance when figuring total mechanical advance - 8 degrees plus ? to give you around 34-36 @ 2500-2800 RPM's. When you reconnect the vacuum advance, it will add 13 more degrees ONLY at no throttle - ie engine vacuum is at its highest. It will vary as the throttle varies. So at 2,500 RPM, Total mechanical is 36, you let off the gas, timing is now Total (36) plus Vacuum (13) and Full Timing is 49 degrees. Give it part throttle (RPM's must be over 2,500 RPM's) and engine vacuum drops and the vacuum advance also drop proportionately - let's say it now only gives you 7 degrees of additional advance. Squeeze the pedal back to the floor, engine vacuum goes to near zero and vacuum advance now drops as well, lets say 0. Timing is now running on mechanical only, or 36 degrees again. Let off the gas, engine vacuum shoots up and vacuum advance adds the 13 degrees again. The vacuum advance is constantly varying based on throttle position which means engine vacuum amount is also varying.


With no load or light load on the engine, the timing will increase up to 13 degrees regardless of what the mechanical advance is, whether it be under 2,500 RPM's and only at 28 degrees mechanical, or idle and 8 degrees. So the vacuum advance has a range of 0-13 degrees on top of whatever the mechanical advance at that RPM is at that time. The addition of the vacuum advance under no or light throttle is what helps to cool the engine and improve gas mileage.


Anything above 2,500 will always be 36 degrees, because that is the RPM you have reached Total mechanical advance - but it will vary between your Initial 8 degrees at idle (650 RPM?) and Total of 36 degrees @ 2,500 RPM's. This spread from 8 to 36 is called your Timing Curve (mechanical) which you could actually plot on a graph showing RPM and the mechanical timing at that RPM - up to 2,500 RPM's (or 2,800 RPM, or 3,000 RPM, or 3,500 RPM - where you choose the RPM where you want Total mechanical advance to be all in at).


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## Baaad65 (Aug 29, 2019)

Ok sounds good, and thanks for the great explanation again, I'll set it up like that...idk why I wrote down 45° @ 2500 it was a while ago and maybe it was learning how to use my new digital timing light but I have notes from talking to Butler that say 34-36° at 2500 just like you said. What do you think of the piece that broke off the distributor, going to be a problem, ever seen that before??


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## Lemans guy (Oct 14, 2014)

Your distributor is toast. It won’t work very well if at all with a missing pole piece for the magnetic Hall effect switch. It may fire six or seven cylinders at best. I would not even put that in the engine.

36 Total is good I still recommend the vacumn setup I previously outlined for you getting max 10 Degrees on vac advance. Those adjustable cans always have too much. Yes it is only 3 degrees too much but still too much.

36 + 10 vacumn....and check for pinging..if so dial base back in 2 degree increments until pinging stops stay there.


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## Lemans guy (Oct 14, 2014)

Maybe there is enough left on top to grab a signal. But if more breaks more problems. You don’t need the most expensive distributor to run great. Just needs to be setup right


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## Baaad65 (Aug 29, 2019)

Well it was running good in the garage which I was surprised so maybe there's enough left we'll see, this can isn't an adjustable so I'll set it like recommended and go from there....it's always something, hopefully it makes it through the summer and maybe Santa can bring me a new distributor 👍


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## Baaad65 (Aug 29, 2019)

Also thanks for the help everyone 👍


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## armyadarkness (Dec 7, 2020)

How do you know that the can isnt adjustable? I thought that all of the MSD cans were.


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## Baaad65 (Aug 29, 2019)

Well I didn't see it in any descriptions and no directions or allen wrench included but I can research it some more also I can get a reluctor gear for 20.00 just need press a new one on...maybe a winter project.


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## armyadarkness (Dec 7, 2020)

Got it. You may want to read this








Correct timing on a mild 400


Just read PJ's post...super helpful. Thanks. I'll consider playing with what I got vs. sourcing another distributor with vacuum advance capability and will try to tune my carb (again) in the meantime. I suck at it and usually mess things up, but practice makes perfect... I've literally set my...




www.gtoforum.com


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## Baaad65 (Aug 29, 2019)

Ok finally got to timing this thing after waiting for some braided hose and fittings, so off the can I set it 8° initial, plugged into the can I'm at 22° so I'm getting 14° out of the vacuum advance...sounds good stabbing it to the floor from idle no hesitation just one pop through the carb the first time I did that but never again. Don't have time for a test flight today but for sure this weekend. How does that sound to everyone?


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## Baaad65 (Aug 29, 2019)

Also got a new reluctor gear but so far this one is working, hopefully I can make it a winter project and I don't end up on a flatbed this summer 👍


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## PontiacJim (Dec 29, 2012)

Baaad65 said:


> Also got a new reluctor gear but so far this one is working, hopefully I can make it a winter project and I don't end up on a flatbed this summer 👍


Sounds like a good start. You at least know what the can is adding.

Are you using a dial-back timing light or a degreed balancer - my brain can't recall? In any case, the above posts can be followed in figuring your total. 

22 can be good. Just make sure it does not start/labor hard in spinning over the engine when hot, but you should be fine.

So 8 + 22 is essentially your Initial with the can hooded up to direct manifold vacuum.

What is needed now is to know (with vacuum can disconnected) what is your Total Mechanical Advance 8 + Distributor Advance (weights) =? AND at what RPM the Total Mechanical Advance (TMA) stops.

A good number I like to start with is 32 degrees TMA (you can use 34/36 as well, I just am conservative at first). So, if you know the Initial is 8 degrees with can disconnected, to get 32 TMA, 32 - 8 = 24 degrees needed from the distributor weights.

If you get 24 degrees out of the distributor weights, keep in mind that you will need to advance (rotate) the distributor to get either 34 or 36 degrees TMA. When you do this, you also advance your Initial (no vacuum can) a like number of degrees. So for each 2 degrees of TMA, you will add 2 degrees to the Initial, ie 8 + 2 (34 TMA) = 10 degrees Initial, or 8 + 4 (36 TMA) = 12 degrees Initial. Now to this you will add the 14 degrees advance from the can when you reconnect the vacuum line, so 10 + 14 = 24 degrees Initial, and 12 + 14 = 26 degrees Initial. This could be TOO MUCH and you can have problems with detonation. You can try it, take it for a test ride with the vacuum line disconnected to see if the engine likes 12/14 degrees. Then hook up the vacuum line and test again, but if issues with the can hooked up but the engine responded well to 12/14 degrees Initial, keep the Initial of 12/14 degrees and hook your vacuum line to a *Ported* nipple on your carb. You should have one of these on the carb.

With a Ported source, the engine vacuum will not pull in the can at Idle as it does from direct manifold vacuum. You may get some vacuum pulling a slight amount from the can, but it won't be much. The difference between ported and direct is that the can won't be pulled in at idle, but it will still work once going down the road. But here is the thing, without the vacuum can hooked to direct manifold vacuum and bumping the Initial 8 degrees to 22 degrees, you may not get the benefits of engine cooling at idle speeds. So kind of a catch 22 here.

The solution could also be to get a vacuum can that only provides 10 degrees additional advance OR adding a stop/limiter to the vacuum advance arm that pulls in on the distributor so it will only pull in 10 degrees. But I won't get into that as that may add more things to consider and confuse. So play around with what you have and report back. If the carb backfires again, it could be that you do need more than 8 degrees of advance. Just stay away from any Detonation during wide open throttle or pulling a hill with the engine lugging. Just back out of the gas pedal and bring it home for more adjusting.


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## Baaad65 (Aug 29, 2019)

Got it, I wanted to check the total without the can but forgot and put the vacuum line back on and had to leave, I do have the curve Butler set up but I need a road test. I'm surprised the can gave me 14° was reading that it would be 10° I'm running about 9.4 compression with one step colder plugs than Butler provided and always use 93 octane so maybe I can run 10° initial we'll see.


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## Baaad65 (Aug 29, 2019)

Sorry forgot to answer you on the timing light, it's a newer Novus digital that you tune the degrees up and down and watch for the zero marks to line up, is that what you consider a dial back light?


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## armyadarkness (Dec 7, 2020)

Baaad65 said:


> Sorry forgot to answer you on the timing light, it's a newer Novus digital that you tune the degrees up and down and watch for the zero marks to line up, is that what you consider a dial back light?


That's the one I bought... It doesnt play well with CDI boxes. Still waiting to try it with a remote power source.


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## Baaad65 (Aug 29, 2019)

No CDI on mine, so bumped the initial timing to 10° no can, plugged in the can and reading about 24-25° mashed the throttle to the floor about six times from an 800rpm idle with no hesitation or backfire. So there was a 10 yard pile of mulch in the way of getting the car out for a test flight so that's gone today and now it's raining on and off of course so stay tuned for an update. Also want to check my idle mixture after all this.


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## BearGFR (Aug 25, 2008)

Baaad65 said:


> No CDI on mine, so bumped the initial timing to 10° no can, plugged in the can and reading about 24-25° mashed the throttle to the floor about six times from an 800rpm idle with no hesitation or backfire. So there was a 10 yard pile of mulch in the way of getting the car out for a test flight so that's gone today and now it's raining on and off of course so stay tuned for an update. Also want to check my idle mixture after all this.


How the car acts sitting in your driveway tells you very little about how it will act driving under load.

Looking back at the chart you posted a few iterations back, with 10 initial in order to get to where your engine's "happy place" probably is you'd want to be using the silver advance stop bushing, which according to the chart allows 25 degrees of travel. 25+10=35, and that's usually a reasonable setting for "most" Pontiacs. 67 and earlier closed chamber heads tend to like more than that, some aftermarket heads with "good" chambers like a little less, but 35 is a good starting point.

Bear


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## Baaad65 (Aug 29, 2019)

That's true, just haven't been able to get it out for a drive since I installed the vac advance, Butler set everything up the way you see it with the 7K3 heads so the only things I changed are the Performer RPM from the stock intake, the carb from an 800 Quad to a 850 dp and now I added the vac advance, so do you think if they had used a distributor with the vac advance from the start they would have used a different bushing or springs or both for a different curve?


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## BearGFR (Aug 25, 2008)

Vacuum advance exists for fuel economy and engine cooling during lightly loaded, part throttle driving - only. It has nothing whatsoever to do with making power, and in fact at WOT there's not enough manifold vacuum present to activate it which is why you always set ignition timing with it disconnected. Springs, bushings, weights, initial timing, etc. are all chosen to establish the optimum "advance curve" for making power. That curve consists of the initial timing setting, the total timing setting (sum of initial plus total mechanical), and how "quickly" the transition from initial to maximum happens - how fast it comes in as RPM goes up. After all that has been "set" for best performance, and only after that, do we add the vacuum can into things for the purpose of - fuel economy and engine cooling during light load/part throttle operation.

How does the can affect cooling? Like so: at part throttle when you're intentionally restricting the air flow into the engine, it's going to tend to run lean. Lean mixtures burn slower. So much slower that they can still be actively burning even after the exhaust valve opens. This tends to really heat up the exhaust valve and port, and the heads, and makes the engine run hotter. Advancing the timing to light the fire earlier gives that lean mixture more time to burn completely before that valve opens - which helps cooling. 

Fuel economy? Making sure that lean mixture is more thoroughly burned before the valve opens helps to extract as much of the energy from the burning fuel as possible, instead of opening the valve "too early" and allowing that energy/pressure to escape out the exhaust port. This helps fuel economy.

It's very common on race engines to not have a vacuum can. In fact back in to 60's some high performance engines, such as the Ford "High Performance" 289 that came from the factory with a dual point distributor, likewise the high performance 375 horse 390 in 1961, didn't have a can at all. That's one of the "tells" you can use to identify the genuine article.

Bear


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## Baaad65 (Aug 29, 2019)

Got it and I knew the can was out of the equation after idle and I shouldn't have asked but I already posted, I'm just curious why if this wasn't a race motor why Butler deletes the can, my understanding is they built it for a guy with a Firebird as a sleeper and when I called and talked to Jim Butler about it he said they don't use them because they're unpredictable so I guess I took his word as gospel. So you're saying using the silver bushing makes for a better curve in my setup and does it have to do with the parts I changed out from the Butler build? Also forgot to mention I changed out the rockers to 1.65.


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## BearGFR (Aug 25, 2008)

Well, I'm sitting here at a keyboard and have no experience with your car, how it's built, etc. So don't change the world based on my say so.

What I'm saying is that "most" Pontiac engines running post '67 factory cast iron, open chamber heads tend to be at their best running >in the neighborhood< of 35 degrees total mechanical advance, with that being "all in" by 3000-3200 RPM. It's a generalization - on average - usually - etc. 
It's very possible that a specific engine might do best with a quite different setting. The best way to find out what's right for an specific engine is to tune it on a dyno, or optimize it at the track under strictly controlled and repeatable conditions. 

It's that total figure - 35 degrees in my generalization - that's the most important and is the figure you tune to. You can get there with 10 initial + 25 in the distributor, 15 initial + 20 in the distributor, or even 20 initial and 15 in the distributor. The initial setting doesn't matter a WHOLE lot as long as the engine isn't hard to start (too much initial makes it want to run backwards as you're turning it over), and also doesn't cause detonation/pinging on a hot day, under heavy load, at 1000-1500 rpm "or so". 

I run my car (a fairly healthy solid roller 461 with Edelbrock RPM Aluminum heads at 10.5:1) at 14 initial, 20 in the distributor for a total of 34, all in by 3000 because that's what it seems to like the best. It also has a vacuum can on it, but either I've never bothered to measure what it adds, or I've forgotten. 

If I was trying to optimize an "unknown" Pontiac with open chamber heads, I'd probably start out with 32 degrees total, test, and then add in a degree at a time, testing each time, until I found the setting that gave the quickest ET's. 

When I said "silver bushing", I was working from two bits of intormation: you said you had your timing at 10, and I saw from the previous chart that the silver bushing puts 25 in the distributor -- so 10+25=35. The factory timing (6) would put it at 31 total with the silver bushing - very reasonable and safe, and to be honest, not a bad place to start out from while trying to find the optimum setting.


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## Lemans guy (Oct 14, 2014)

well said Bear, racers see Vacumn advance as something they don’t need which is true. But let’s say a guy is going to a 1/4 mile track and going to do 4 full throttle runs. The Vacumn is not there at WOT so the can adds no timing, but at the end of his quarter mile pedal down he will let up real fast on the pedal and instantly add that timing back in. It could ping them, especially if the can is pulling 20 plus degrees which is like many I see.

he could easily just pull and plug thevac can go his 4 runs and plug it in when he gets ready to drive home.Or even just leave it hooked, but he does not want to bother with it.

Vac cans today on today fuel blends should add no more than 10 degrees, I set em all up at full manifold vac 10 degrees.

many racers don’t understand vac advance or care too, but understand that any computer on a modern fast car is adding the same amount of timing in at idle and part throttle that you get from a vac can.

The distributor was the mechanical computer of the day, it deliver spark at the correct sequence, at the right time, based on the right RPM-and based on engine load, removing the vac can is like disabling part of it.

but guys look in some fast car at the cruise in and they don’t see a vac advance, and it has billet everything so it must be cool racer stuff.

well it may have a computerized timing element which is adding that idle timing and light cruise timing that the vac can delivers. Or it may be a racers car who does not need it, he thinks.

If you drive it on the street at all, vac advance set-up properly...(most are not, too much timing and wrong HG,...) you will benefit from stronger light throttle power, cooler running, cooler idle, more efficient burn, which helps power and efficiency at light throttle, and no adverse effect on heavy and WOT.

So why wouldn’t you set it up correctly? It is not an expensive proposition!


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## BearGFR (Aug 25, 2008)

You're absolutely right, and I run a can on my car.
There's a lot to be said about people who merely copy what they see (or think they see) someone else doing, but don't know why they're doing it or why it might be a bad idea for their personal situation.

Bear


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## Lemans guy (Oct 14, 2014)

Yes, curved to distributors last week both had way to much timing from vac advance. They often have 20 plus degrees, add that to 36 and you have 56! Too much....on today’s fuel light throttle cruise max timing should be 46 to 48 degrees.....

I always take off those adjustable cans and put on a fixed can that pulls 10 under the idle vac. No adjustments to worry about it works or not and vac will be right!


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## Baaad65 (Aug 29, 2019)

Ok makes sense and it looks like according to the chart the black bushing stops at about 18 degrees, I have no starting issues even when I had initial set at 19 degrees, is hard to hear detonation with the exhaust unless I lug it up a hill or something. Didn't realize the vac advance help cooling that much as I've been chasing overheating at idle issues, went as far as installing to 13" pusher fans on a separate switch for when I'm caught in traffic to compliment my 16" puller, along with more water and water wetter, drilling my thermostat when maybe just adding the vac advance could have solved the problem idk. Again idk why Butler set the curve the way they did and they did say I should be at 34-36 degrees all in at 2500 rpm, they had it on the dyno so they must have had a reason. If I get no starting issues or detonation can I just advance the initial instead of changing the bushing to achieve 32-36 degrees?


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## Lemans guy (Oct 14, 2014)

Yes that is correct, the most important number is your total mechanical advance which is the base timing set with your hand and the centrifigal timing set by the weights as they move out to full mechanical stop. Add together it should be 36.....or 34 or 32 if you want to be conservative or hear pinging.

Vacumn advance never figures in total advance. As far as initial or idle timing you can have a lot. Many cars are set at 18 base + 18 Centrifigal = 36. You can add 10 degrees from vacumn advance on top of that at idle. It will give a cool and smooth idle. You just have to ensure that you don’t have kickback from the timing being too far advanced. But since the modern Petronix and electronic distributor modules almost always retard the timing 4 degrees at cranking, to avoid that, you likely won’t.

if the cam is mild itwill take less idle timing and if radical it will take more. Because radical cams have an even leaner mixture more advance helps smooth out the idle.

Guys just put vac cans that pull too much and drop it on 16 or 18 degrees, might get kickback them keep your vac at 10 degrees. I would not keep trying to make the Centrifigal advance, with the bushing smaller. That gives you no real advantage. If it is at 18 leave it there set your base at 16, that will give you a nice conservative 34 total timing to begin. Drop in a vac can pulling 10 degrees hooked to full manifold vac.

your idle timing, base 16 + 10 vac will idle smooth and cool. Youcan later bump the base up 2 degrees if no pinging is evident, listen and check spark plugs for the specks.

let us know how you do!


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## Baaad65 (Aug 29, 2019)

Sounds good, so the black bushing is 18° so I'll start with 12 and work my way up to a max of 18, that's where I had it with no starting problem but was told that it was to much when I said I was installing a vac advance. Seems like I'm getting about 14° out of the vac can....we'll see how it goes. I thought I knew a few things but turns out I know less than I thought, three years of auto shop and just threw stuff together when I was 18 then I totally got out of cars when I got married so 30 years later I'm trying to educated again, guess I should have followed through on the Wyotech school I was signed up for but bailed at the last minute because of a girl...turned out ok as we're celebrating 33 years in a couple of weeks and she's the one who told me to buy the car and says nothing as I spend thousands and even goes to all shows with me but I do have to take her to the beach twice a year oh and there's the 2013 purple Challenger I got her because of a guilty contients 😉 thanks for everyone's help, I love learning and I understand it once explained 👍


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## Lemans guy (Oct 14, 2014)

You are doing great. Baad!.......you are knowledgeable about classics or you would not be doing this! Some guys never pay attention to timing, AFR mixtures, ignition systems fuel delivery etc but can hand build a great engine. Or be a fabulous paint and body man.

I had a friend tell me how brilliant their surgeon was one time, and I agreed, that’s takes study knowledge and experience. But I said I bet that he cannot fix the fuel injection system on his BMW. But there is someone, a BMW Master Tech who can, and he also has study, knowledge and experience.

Anyway once you get that done we will help you get that vac down from 14 to 10 degrees....if you come this far you want it to be perfect!


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## Baaad65 (Aug 29, 2019)

Thanks I really appreciate it, I timed it up today...so I set the initial with no can at 16° + the 18° from the can, (that's what the black bushing max is according to the MSD instructions) so that's







34° but then of course it started raining so no test flight..also adjusted the idle mixture with my old Hastings vacuum gauge to the highest reading so we'll see how it does, car show on Sunday. One encouraging observation is I had it idling for about 30 minutes in my 85 degree garage with just the 16" puller fan running and it barely got to 200 degrees so the vacuum advance must be helping and the drilled 160 stat or both, it always ran way hotter just idling.


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## Baaad65 (Aug 29, 2019)

Miss spoke again, the 18° is from the mechanical advance duh


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## Lemans guy (Oct 14, 2014)

So you have 34 degrees total advance ......16 base +18 Centrifigal. And 14 you think from the vac advance....that would be 30 degrees at idle......16 base + 14 vacumn if you are hooked to full manifold vac.


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## Lemans guy (Oct 14, 2014)

Eventually you will want to make that vacumn 10 degrees, so your idle will be 26.....16 base + 10 vacumn....it will run cooler at these advance settings


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## Baaad65 (Aug 29, 2019)

Correct, so 30° total is a little to much, will it contribute to higher idle temps that bad you think? Maybe I can make a stop for mine or ditch it for an adjustable if it will fit the MSD dist. I should have checked the timing with it connected to the can but forgot, I'll do that soon to make sure what it's giving me but that's what I remember from the last time.


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## PontiacJim (Dec 29, 2012)

Baaad65 said:


> Correct, so 30° total is a little to much, will it contribute to higher idle temps that bad you think? Maybe I can make a stop for mine or ditch it for an adjustable if it will fit the MSD dist. I should have checked the timing with it connected to the can but forgot, I'll do that soon to make sure what it's giving me but that's what I remember from the last time.


No, 30 degrees won't cause higher idle temps, but it is pushing it as you don't want any kind of detonation. Granted, the minute you push the "go" pedal, vacuum drops so you will lose the extra advance from the vacuum can and fall back on just mechanical advance. However, there is typically a slight lag because the vacuum can does not react like "right now." So you could experience a a momentary experience of engine detonation - not the best thing as it'll be short lived, but not the best either as "no detonation" is what you want.

This could also be experienced when you are just cruising along on light throttle, the vacuum can could reach it's max point and timing pulled to a full advance, and then you drop a fast/hard shift. The vacuum could take a second to escape out of the can/line and you will get a little "pinging" that clears up rather quickly, but you may hear it and wonder why. So too much advance added to the mechanical advance in this case would not really be what you want, thus *Lemans guy'*s recommendation of limiting the vacuum advance to 10 degrees with the numbers you have.

This is not a text book situation where you can set the degrees and let it rip. Each engine combo is different and that is why it is up to you to fine tune and dial the timing in for your car. You are doing fine with it, so just keep moving forward with it and report what is going on and we can get the timing right where your engine likes it...........and just when you thought you had it set perfect, it'll change on you just because it can! LOL BUT, you will know exactly what to do and adjusting the timing again will be a cinche - and you will be a pro like us old farts and someday be explaining how to do this to the next younger generation who wants a GTO and hasn't a clue how to work on it.


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## Baaad65 (Aug 29, 2019)

Thanks so much, if I could just get it out for test drive I could see how it works, did some searching and looks like they don't make an adjustable advance for my dist. Hopefully the 93 octane and the 9.4 compression help me out or I'll just have to put it down to 14° initial if I hear popcorn being popped. Also I noticed that it looked like I was all in on mechanical advance around 2000-2100 not 2500 so idk if I should fool around with heavier springs?


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## LATECH (Jul 18, 2018)

My 389 i run 14 base (initial ) timing.The mechanical is set to pull 20 degrees at 3000 rpm and above.
Runs like a striped A $ $ ape.

I have a Crane vacuum advance and a summit spring kit. I run the factory weights , but a blue and silver spring.

The vaccum advance. I have the spring tension set light so it comes on easily ( quickly) and I have the amount locked at 8 degrees ( with the lockput cam provided) so I dont get too much timing at low RPMs and end up with a knock/ping.
It works flawlessly
The vacuum is for pulling some timing at low RPM to help build power and eliminate flat spots when sudden throttle openings cause the mix to go lean.
It also helps pull timing at low cruising speeds for added economy. All this is of course based on running PORTED vacuum, not manifold .
Ported -manifold-- to each his own


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## Baaad65 (Aug 29, 2019)

Ok good to know, ya my vac advance is manifold, I'm running a light silver and a light blue with a black bushing, seems like the vac can is giving me 14 degrees and I thought when checked it with my light yesterday I was all in at 34 degrees at around 2000-2100. this is how I got it curved from Butler but without the vac advance, I just added that. Wondering if it should be all in not until 2500 that's what Butler told me, I posted my curve chart on the previous page. Also curious if I have to change anything because I've changed intakes from the stock one and the carb to a bigger one and changed the rockers to 1.65, would that effect the curve I need ?


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## PontiacJim (Dec 29, 2012)

Baaad65 said:


> Ok good to know, ya my vac advance is manifold, I'm running a light silver and a light blue with a black bushing, seems like the vac can is giving me 14 degrees and I thought when checked it with my light yesterday I was all in at 34 degrees at around 2000-2100. this is how I got it curved from Butler but without the vac advance, I just added that. Wondering if it should be all in not until 2500 that's what Butler told me, I posted my curve chart on the previous page. Also curious if I have to change anything because I've changed intakes from the stock one and the carb to a bigger one and changed the rockers to 1.65, would that effect the curve I need ?


200-2100 is probably too soon. I would not go any earlier than 2,500, but you can test it. 2,800 might work better as could 3,000 RPM's for the street and pump gas. You are simply "stretching" the timing curve so it comes in slower - which means a slower timing advance before reaching your total timing number, and less chance for detonation.

If you were using a race gas with higher octane that resists detonation, you might be able to be all in at 2,000-2,100 RPM's.


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## Lemans guy (Oct 14, 2014)

Agree, 2100 is too low, you will get detonation on the acceleration. Put on springs a little stronger. 3000 is great. I do set Corvette’s up for 2500, but Taney are different and call for that.

I don’t want to read all back through this thread, is this an HEI distributor coil on top? Or a narrow body distributor with external coil? MSD makes both....


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## Baaad65 (Aug 29, 2019)

Ok re checked just now, so 16° initial 34° all in at about 2300 now







, vacuum advance plugged in I'm at 30° checked the springs and looks like a light silver and light blue but I don't have any other springs to compare with so maybe I'll get a kit


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## Baaad65 (Aug 29, 2019)

Well I've never heard any detonation and it's a narrow top, separate coil.


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## Baaad65 (Aug 29, 2019)

So help me understand this graph because it shows me the advance is all in not until 3200 but all the graphs only show a maximum advance of 28° or is it where the black bushing marker intersects the climb in advance about 2200.


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## Baaad65 (Aug 29, 2019)

Maybe I want the curve in the graph above, two light blue springs.


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## Baaad65 (Aug 29, 2019)

Again Butler set this curve up in 2014 so idk if they go for max horsepower or what but there tech told me 34-36 all in by 2500 but that's not what their curve is doing if I'm reading things right.


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## Lemans guy (Oct 14, 2014)

Those charts on bushing do vary a bit. Sometimes the bushing is spot on other times not. But you have 18. You tested with your timing light @ 34...16 base.

The springs also vary from these Chartres charts, many are way off, get a curve kit, you can get an MSD one, but any GM one will work. And try a blue and silver spring to start with. The kit will have a chart too, the charts are just not that accurate. Try em and test em. Get as close to 3000 Rpm as you can. Most of them I have to use two different springs to get the desired curve. Sometimes two can match.

you are close like bear said fix this then vac can. You will want to limit it. I set them all to full manifold vac. Why give up that extra 10 degrees of advance that smooth’s the idle and aids cooling.

With 20 degrees at idle vacumn that cam is not giving you a lot of “reversion” which is contamination of the fuel mixture from the exhaust overlap. I would have set your bushing for more like 22 or 24 degrees Centrifigal, then make the base 14 or 12 for 36 total.

with that 12 base and 10 vac a smooth cool idle at 22 would be good with that high vacumn...

you have 20 degrees idle vac. You don’t need 28 and 30 degrees idle timing and 14 base gives up a lot of cooling. So you have room to adjust and be a strong runner.


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## Baaad65 (Aug 29, 2019)

Ok a lot to process there so bear with me so a bigger advance bushing for more mechanical advance correct? And what's the difference in turning the distributor to get more advance? The vacuum advance adds 14° so idk if I can find an adjustable one or a fashion a stop of some kind. I'm picking up a MSD bushing and spring kit from O'rileys tomorrow. For what it's worth I'm making about 16" of vacuum and here's my ca







m specs but I have 1.65 rockers.


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## Baaad65 (Aug 29, 2019)

So I meant a smaller bushing they come 21, 25, 28 and I have a light silver and light blue springs now so the next slowest curve is two light blues. Also the MSD directions say the vacuum advance should be 10° so idk why I'm getting 14 ° out of it ?


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## armyadarkness (Dec 7, 2020)

Yes... If you want to keep your all in number the same, but you want to reduce your base timing, then you need to allow more mechanical advance, by swapping the bushing. 

In other words, if you want to reduce your base timing two degrees, then increase your mechanical bushing two more degrees.

BTW, your numbers are like mine... high base and vac, to achieve 36, so I need to do the same.


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## Lemans guy (Oct 14, 2014)

Ok make this easy. Try the 21 bushing, set your base at 13 for a conservative 34 total. Check and verify, bushing could be off a little adjust base to get 34.

you can try to adjust the MSD can thru the snout with an Allen wrench if that is the kind you have. I ditch those and have a stack under my distributor machine, often they don’t have fixed stops, and the vacumn totals are very high and sloppy. The crane one LA tech mentioned has a physical stop that works.

Here is what I recommend, you have 16hg idle vac, you need a B26 Vacumn can

Get a Standard Motor Parts (SMP) BC 181.....rock auto has them. Standard makes them all, Different stores use different numbers.

O’Reilly Part #BWD V375
NAPA Part # VC1808

the specs on this B26 can are. 5-7hg. 8*@11-13

This means that the can will start pulling timing at 5 to 7hg and will pull 8 degrees distributor, which is 16 degrees at the crank timing, and be fully deployed at 11 to 13 Hg. Which is just below your idle vacumn which is where you want it and it will not dither in and out effecting timing and idle.

get that can about $15. Then email Lars; [email protected] and buy one of his vacumn correctors, about the same price. Install the corrector on top of the vac can. He will send a sheet with it. I have put them on MSD’s like yours. That corrector will knock the crank timing back to 10 degrees.

now you can try the springs from the kit, try a medium and light. Get close to 3000, 2800 good so is 3200, sometimes you can get it exact but not always. I have a box of springs and have tried 20 or more combo’s on some distributors tuning that curve.

check drive it it will be great, your idle timing at 24.....14 base and 10 vac will run smooth and cool, you really don’t need much more than that. Lower tends to make a hotter exhaust and burn a tad more fuel and be less efficient. You will see. Plug the vac can idle at 14 base. Now hook up vac can and see how much smoother that idle is recheck that reading should be 24 or pretty close. Minor adjustments may always be necessary as you set it up.


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## Lemans guy (Oct 14, 2014)

Correction typo 

Standard Motor Parts VC 181


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## armyadarkness (Dec 7, 2020)

What does the Lars corrector do? I keep meaning to ask.

Also, his dizzy, like mine, is the divorced coil HEI type, so we need the cans for the old point style, correct?


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## Lemans guy (Oct 14, 2014)

The Lars corrector knocks the timing back from 16 degrees to 10 degrees. There is no vac sold for a points style distributor that gives 10 degrees. Except some adjustable that say they can be set at that. Some can, but it never seems very uniform or straightforward.

on dizzy’s for the 60’s 70’s GM you have 2 different styles. Points and HEI,...but for vac cans the real difference is in the diameter of the distributor. Points “style” dists with external coil have a narrow diameter, just like the original. While HEI with coil on top of the cap have a wide diameter. Made to keep the hotter spark from jumping terminals.

Consequently, the vacumn cans that fit on a points dist are too short for an HEI, and the vac cans for an HEI are too long for a narrow “Points” style distributor.

If you are running an HEI wide diameter, don't buy the B26 can, it will not fit. But there is a vac can I use all the time on HEI that pills in low vac and 5* degrees distributor which is 10 degrees at the crank and no corrector is needed.

the B26 with Lars corrector is a great foolproof set up and fits many of our Pontiac’s well. Cars with super low idle vac may need a B28 vac can, some may need a different one.


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## Lemans guy (Oct 14, 2014)

Just a note we all refer to HEI type distributor, but we mean it has electronic or magnetic switching and not points. But that does not tell you the diameter. The electronic switch inside has nothing to do with timing.....

you would not believe the number of guys at cruise ins who say I don’t need my timing curved as I have HEI or a Petronix module. That changed only your mechanical points switch to a Hall effect magnetic sensors, or other electronic or light sensor, itdid not change your timing.

there are computerized modules that will adjust your timing inside distributor and you can set it yourself. A different distributor set up altogether.


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## Lemans guy (Oct 14, 2014)

The HEI distributors are 5.25 diameter, the Points style are 4 inches. Measure and be sure as MSD makes both sizes and many models. If you are using the narrow style points the B26 can and Lars corrector will fit. If you have the wide diameter HEI style, I can give you info on another vac can to fit that with no corrector that will pull 10 degrees at the crank.


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## Baaad65 (Aug 29, 2019)

Ok I get what you're saying, how about this idea say I don't want to mess with my vac advance can right now what if I use a 28 or a 25 degree bushing and find a happy medium for both mechanical advance and idle advance, here's a chart I made up so tell me if I'm off base with idea and what numbers you like best.


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## armyadarkness (Dec 7, 2020)

It's worth mentioning that people have been running these cars, timing them to the "label" at 6 degrees, and never paying any mind to vacuum advance, for well over 50 years, without any issues. The people here are telling you how to get the most out of your engine. Mileage, power, efficiency, cooling.

God isnt going to come down from Heaven and put you in a time-out, if you don't follow this to the letter. All any of this is, is a base setting. You will need (or want) to cater each area, to what your car likes.

This is why they keep saying "conservative" settings. There's no requirement to sap each single horsepower out of the car. There's a lot to be said about "if it aint broke, don't fix it". My car runs like a clock, but I feel like it's down on power, so I'm going to tweak my timing. But if I see know improvement, then I'll put it wherever it runs best, even if that's 30 degrees.


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## BearGFR (Aug 25, 2008)

Baaad65 said:


> ...here's a chart I made up so tell me if I'm off base with idea and what numbers you like best...


Doesn't matter one iota what any of us "like best". What matters is what your car likes best, and the only way you'll ever find that out for certain is through testing your specific car.

All the recommendations we've all been making have all been "in general" based on experience. Like they say on TV "your mileage may vary, void where prohibited by law, past performance is not a guarantee of future return, slippery when wet."

Just from personal experience, your car will "probably" like "something in the neighborhood of" 33-35 degrees total. 

For example,10+25, or 7+28, or 15+20 ---- all work out to 35 total. The details of how you get there "probably" won't matter much and you'd never feel the difference in your seat-pants-o-meter, and maybe not even on an atomic clock. 

Don't be afraid to experiment and try things. You're not going to hurt anything by doing that. Try something, go drive it - start by driving it 'sedately', and if nothing untoward happens and you don't hear any pinging/knocking, then start asking more of it. Detonation kills engines over time - but a 'little bit' that you detect during testing isn't going to hurt anything especially if you hear it and stop loading the engine enough to cause it.

Bear


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## Baaad65 (Aug 29, 2019)

All true, I think it runs good now and goes like a bat out of hell when you mash the go pedal with no starter problems and no detonation that I can hear but I guess it could be better the way it sounds, like my all in advance is to soon and my idle advance is to much so I'm just trying to get the best curve that helps all the causes but some might have to suffer a little for other ones, so which is the most important? Obviously no detonation that's a bad one, over heating at idle, more power with a wider band, smooth cooling idle , and everyone seems to agree I need get the all in mechanical advance in a higher rpm range.


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## armyadarkness (Dec 7, 2020)

Baaad65 said:


> I think it runs good now and goes like a bat out of hell when you mash the go pedal with no starter problems and no detonation


You're completely answering your own question.


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## Baaad65 (Aug 29, 2019)

picked up the curve kit and now they include 6 bushings...28, 25, 23, 21, 19, 18...now I have to make a new chart


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## Baaad65 (Aug 29, 2019)

Ok so I think my first stab at it is going with the 28 degree bushing set distributor at 7 for 35 total, gonna try and work with my vac can so 7+ 14 = 21 idle advance. So I'm a little confused on the spring chart because if I change to the 28 bushing it shows it's all in at 3100 with my springs ( light blue and light silver) so how does the bushing effect speed of mechanical advance I thought it just limited the total advance not the rate. We're all saying I need to stretch the curve out to 3000 but if I use the next slower curve it's showing all in not until 3800 rpm...see my chart pix.


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## armyadarkness (Dec 7, 2020)

I mustve missed something. Im no expert, but if the car "runs like a bat out of Hell, with no side effects". Then I would not be touching the timing, or anything else for that matter.


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## Baaad65 (Aug 29, 2019)

Well I guess because my idle advance is to much now with the vac can and my all in advance is to soon, so maybe I can make it a faster, cooler running bat out of hell 👍


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## Baaad65 (Aug 29, 2019)

Quick update, installed the 28° bushing set timing at 7° and now I'm all in at 35° @ 3000 rpm, plug in the can and I have 21° numbers worked out just like they should....BUT now I have a stumble or hesitation when I mash the throttle from idle that I didn't have before so more tuning to come but I had to run out and it was raining.


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## Lemans guy (Oct 14, 2014)

Lot’s of choices. I would just suggest put in the 23 bushing and set base at 11 =34

now add your vac can + 14. For idle of 11 + 14 = 25....

when you later fix the vac can at 10 you can reset the base from 11 to 13..which will be 34,35 or 36. And idle at 23......when at 36

I set them all for 36 and then adjust but 34 is a good start as well.

as the guys there is not a wrong way in these ranges it is what the car likes. Don’t use the 28 bushing it ramps the timing up to fast.

the light springs just achieve the distance the weights travels faster.....it is time based on rpm’s

heavy springs bring the distance the weights travel in slower....time vs RPM’s

Don’t get too hung up on those charts as the spring charts will vary, try em test and enjoy iy


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## Baaad65 (Aug 29, 2019)

So you think it needs more advance to get rid of the stumble? And 25 at idle isn't too much? I didn't change the springs still one light blue one light silver, still don't know how a bushing changes the rate of speed the advance comes in but it did, thought I would have to change springs but it's in at 3000 👍


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## Lemans guy (Oct 14, 2014)

Our messages crossed here, by using the 28 degrees the timing is not enough initial for a smooth transition, use the 23 and see what I said above. And definitely get the vac to 10 sometime


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## Lemans guy (Oct 14, 2014)

No 25 is ok at idle, but 28 is too deep on Centrifigal, what happens is at idle when you MASH the pedal....the vacumn drops out and the RPM’s have not caught up yet....so you are left with 
7 degrees base or close to that and you stumble....

make it 23 on the bushing and 11 to 13 on the base and that should smooth out,..

The bushing shortens or lengthen the amount the distributor center cam travels, if you looked at bushing closely the 28 would be thinner than the 18 the 18 thicker, so the thicker one limits how far the weights affect the movement of the center cam on the dist. It has less distance to travel to reach full stop, so the same set of springs will bring it to that stop at different rates.


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## PontiacJim (Dec 29, 2012)

Baaad65 said:


> Ok good to know, ya my vac advance is manifold, I'm running a light silver and a light blue with a black bushing, seems like the vac can is giving me 14 degrees and I thought when checked it with my light yesterday I was all in at 34 degrees at around 2000-2100. this is how I got it curved from Butler but without the vac advance, I just added that. Wondering if it should be all in not until 2500 that's what Butler told me, I posted my curve chart on the previous page. Also curious if I have to change anything because I've changed intakes from the stock one and the carb to a bigger one and changed the rockers to 1.65, would that effect the curve I need ?



OK, again, forget about the vacuum can for now. Get your Initial and Total zero'd in. You have 16 Base and the distributor is giving you another 18, so 34 Total Mechanical. Get the springs that will pull the 34 Total in around 2,800-3,000 RPM's.

Take it for a spin without the vacuum can connected. How does it do?

If this is good, here is your problem. When you connect the vacuum can to direct manifold vacuum, _Base will jump up another 14 degrees_ to 30 -which is too much.

So, at idle, get a vacuum reading from the engine - direct vacuum. I believe you said 15 Hg. OK, now find a port on the carb that is "ported." The "ported" nipple will show no-to-very little vacuum by design. If you hook up to a direct vacuum port on the carb, it will be the same as what you just got off the engine earlier from the manifold - 15 Hg. You do not want to use this one.

Once you find the "ported" line on your carb, you are going to use this for your vacuum can. Aim your timing light at your Initial (16 degrees), and then connect the vacuum can line up to the "ported" nipple on the carb. See IF it moves up a few degrees, ie to 18 Base. If it does, then it may work perfect for you hooked to "ported" vacuum.

Take it for a spin and see what you think with ported vacuum connected.

If it works with "ported" vacuum, then you do not have to mess with limiting the vacuum can to something like 10 degrees max as *Lemans guy* pointed out.. You can use it as is. The vacuum can only provides full vacuum, 14 degrees, when you let off the gas or under light/part throttle loads. You don't get "pinging" under light loads and this is where the max 14 degrees pulls in to increase total timing (based on your RPM at the time) so it cools the engine temps and gives better gas mileage.

Now *if "ported" does not agree with the engine*, then you are back to making timing adjustments all over again based on direct manifold vacuum. You still want 34 degrees Total at 2,800 - 3,000 RPM's. BUT, with the direct manifold vacuum now pulling full on with the vacuum can, you have to take this amount and add it to the Initial. Base (Initial + vacuum can OR Inital no vacuum can) should be around 20 degrees at idle. If the can pulls in 14 degrees (which we know) then in order to get the Base at 20 degrees at an idle, subtract the known 14 degrees of vacuum advance from the desired 20 Base and you get 6 degrees. So, this means that without the vacuum can connected, set your timing mark on the balancer to 6 degrees at idle - this is your new Initial timing. As soon as you reconnect the vacuum can, the Base timing (Initial + vacuum can) will jump up to 20 degrees, 6 (balancer) + 14 (vacuum) = 20 Base at idle. Got it?

Now, you will have to change the bushing out in the distributor. Why? Because you presently have it set for 34 degrees Total timing and the Base (Initial - no vacuum can) at 16 degrees idle. Once you connected the vacuum can to direct manifold vacuum, the Base becomes 30 degrees, 16 (Initial) + 14 (vacuum) =30. You can't have 30 Base - too much. So to get the numbers I just provided in the previous paragraph and *using full manifold vacuum because the ported vacuum did not work* for your, you will set your Initial timing at the balancer to 6 degrees at idle. BUT, when you do this, you are going from what was previously 16 degrees down to 6 degrees - you are dropping your Initial 10 degrees. 16 (Initial) - "X" = 6 (your new Initial setting with manifold vacuum). "X" = 10 degrees, right? 16 - 10 = 6 degrees. Not sure how well the engine will run at 6 degrees? But, this is only for setting up your timing with full vacuum, so it won't be a problem once the vacuum can is hooked up.

You are losing 10 degrees of advance down at the balancer. So what does that mean? It means you are also dropping the Total timing back the same 10 degrees because you have to rotate the distributor to retard the timing to get 6 degrees to show up on your balancer (no vacuum advance). So what was 34 degrees will become around 29-30 degrees because you moved/rotated the distributor to get 6 degrees on the balancer. So you will now need to change out the stop bushing/limiter in the distributor using your chart to give you more weight advance so that you can get the Total back up around 34 degrees. Do NOT mess with the springs.

OK, so now you have your Initial and Total set without the vacuum can. Perfect. Now hook up the vacuum can and watch the Initial 6 degrees on the balancer jump up to 20 degrees - which is now your Base timing at idle. You should still only have 34 degrees Total at 2,800-3,000 RPM's - if not then you can play with the springs to get this back again. Total, 34 degrees of advance, is *UNDER LOAD/WIDE OPEN THROTTLE,* and at 2,800 - 3,000 RPM's and above*.* It will not advance any more, got it?

*HOWEVER*, it will advance more!! WTF, saaaaay what? It will _ONLY_ advance more when you lift off the gas or use very light throttle to keep the car rolling *BECAUSE* the engine vacuum will build up and pull in on the vacuum advance can. So technically, If you are at 34 degrees Total, 3,000 RPM's and above, and you let off the gas pedal, the vacuum advance will pull in, at most, another 14 degrees. So you get 34 + 14 = 48 degrees of timing advance - EXCELLENT! Just what you want because this helps to cool engine temps and better gas mileage *WHEN* you lift your foot off the gas or just use a light pedal to keep the car cruising along. Push the pedal hard or stomp it, the engine loses vacuum and the extra degrees of advance from the vacuum can gets lesser or goes completely away and you fall back on just the mechanical advance only - until you lift you foot again. This process repeats over and over again as you drive, always changing based on RPM, mechanical advance, engine vacuum, and your foot.

Another read which may also help explain:






Where should I set the timing on my performance engine?


Bad-Ass Racing Engines specializes in building some of the baddest street and race engines around!



www.badasscars.com


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## Baaad65 (Aug 29, 2019)

I'll get on it and thank you very much again for all the help, will report back when I get done.


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## PontiacJim (Dec 29, 2012)

Lemans guy said:


> No 25 is ok at idle, but 28 is too deep on Centrifigal, what happens is at idle when you MASH the pedal....the vacumn drops out and the RPM’s have not caught up yet....so you are left with
> 7 degrees base or close to that and you stumble....
> 
> make it 23 on the bushing and 11 to 13 on the base and that should smooth out,..
> ...



Check out my take on the timing and comment on what you think - it's OK to be critical, just want to get it right.


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## Lemans guy (Oct 14, 2014)

If I was setting this for you I would set 23 centrifigal with the bushing, 13 base for 36 total,.....and 10 vac at full manifold vac 

for 23 @ idle...13 base + 10 Vac


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## Baaad65 (Aug 29, 2019)

PontiacJim said:


> Check out my take on the timing and comment on what you think - it's OK to be critical, just want to get it right.


I really appreciate all the great advice and getting quite an education like I had no idea that to much idle advance lead to engine heat and I trust you guys better than looking all over the internet and finding false information...by the time I get this dialed in I'll be opening my own curve shop...NOT


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## Baaad65 (Aug 29, 2019)

The only thing is I'm going to stick with the manifold vacuum because I got an unfinished dual port fitting and polished it up and two barbed fittings (one goes to my stock Pontiac vacuum gauge on the center console that looks great) and braided line with nuts that came out nice, I'd have to redo all of that and buy more line to go to the front of the carb for ported vacuum so we'll see how this works.


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## RMTZ67 (Mar 12, 2011)

Baaad65 said:


> So you think it needs more advance to get rid of the stumble? And 25 at idle isn't too much? I didn't change the springs still one light blue one light silver, still don't know how a bushing changes the rate of speed the advance comes in but it did, thought I would have to change springs but it's in at 3000 👍


I am no timing guru and had to go to the Timing professors as well. For what its worth...I had been chasing a stumble for some time. Added high flow needle and seat, new fuel pump, raised my float, messed with the secondary's, etc. A couple of weeks ago I decided to advance my timing slightly just for the he!! of it... and to my surprise my stumble went away. So if you end up there, its a option.


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## Lemans guy (Oct 14, 2014)

Yes timing lags can sometimes cause a stumble mostly they are fuel air related. I prefer manifold vac, but you can use ported as PJ throughly described. Once you tune your mind it to what the engine is doing you can set it right.

you have to marry up how the engine runs and feels to you while you are setting up these numbers. If right it will all coincide, don’t dismiss any old school techniques or how you feel it runs, those matter.

But when it is right you will know the reasons. I like adding that 10 degrees at idle from vac and find most engines idle


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## Lemans guy (Oct 14, 2014)

Smoother and cooler!,... I also like the transition from idle it is subjective I guess but ported is picking up the vac as you accelerate lightly while with manifold vac it is already there and stays there....

maybe it is imperceptible, but to me it feels smoother...but neither way is wrong...just preferred for certain reasons.

I


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## Baaad65 (Aug 29, 2019)

Got it, changed the bushing last night but got late so I'll time it up today, bad weather today so maybe tomorrow I can finally get it out for a real test. I know it's not the best thing but I'm going to try and work with my vacuum advance can since it's all in place, hopefully 11° clears up the stumble and I'll have 25° at idle and maybe that will work 🤞 have a feeling I'll have to change a spring to get back to the 3000 all in mark, I'll post up the results 👍


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## Baaad65 (Aug 29, 2019)

To bad I don't have a port in the back of the carb I would try that.


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## Lemans guy (Oct 14, 2014)

You could, but I never use ported...you will get it


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## Baaad65 (Aug 29, 2019)

PontiacJim said:


> OK, again, forget about the vacuum can for now. Get your Initial and Total zero'd in. You have 16 Base and the distributor is giving you another 18, so 34 Total Mechanical. Get the springs that will pull the 34 Total in around 2,800-3,000 RPM's.
> 
> Take it for a spin without the vacuum can connected. How does it do?
> 
> ...


So I read this article and two things I noted...# 1 he said mechanical should be all in by 2500 and that 3000 is to late/high so that's different than what I've been hearing here, # 2 he said he likes only about 10 degrees of mechanical advance and the rest of the 36 total advance done with the distributor/timing light marks, so what do you make of this?


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## Baaad65 (Aug 29, 2019)

Ok got home early timed her up, 23° bushing 11° on the light, all in at 34° right at 3000rpm, 25°on the can..no hesitation stabbing the throttle to the floor from idle 👍 pouring here so the test flight will have to wait until tomorrow but it sounds encouraging, I know the idle advance is a little high but better than 30° 👍...time for some Jack 😉 and thanks for everyone's help I'll report back after the flight.


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## Baaad65 (Aug 29, 2019)

...I'm just surprised the all in @ 3000 still held and I didn't have to change any springs. How will I know if I should go one spring heavier or lighter, will I feel it in the seat of the pants? And on the drive I'm looking for no hesitation, no detination anything else? any special driving procedures that are recommended for testing the timing and advance?


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## PontiacJim (Dec 29, 2012)

Baaad65 said:


> So I read this article and two things I noted...# 1 he said mechanical should be all in by 2500 and that 3000 is to late/high so that's different than what I've been hearing here, # 2 he said he likes only about 10 degrees of mechanical advance and the rest of the 36 total advance done with the distributor/timing light marks, so what do you make of this?


Correct - he builds race engines for the most part, so a slight different set-up. Keep in mind race builds use race octane gas as well, so you can do the numbers he has stated. Just more info in general to digest...................and confuse you.


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## PontiacJim (Dec 29, 2012)

Baaad65 said:


> ...I'm just surprised the all in @ 3000 still held and I didn't have to change any springs. How will I know if I should go one spring heavier or lighter, will I feel it in the seat of the pants? And on the drive I'm looking for no hesitation, no detination anything else? any special driving procedures that are recommended for testing the timing and advance?


Nope, numbers look good. Just turn it on, wind it up, blow it out, GTO. Just pay attention to how it responds and "no pinging" when you lug the engine or WOT.


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## Baaad65 (Aug 29, 2019)

Ok, I mean it ran lights out before but maybe it will be even better and cooler with better mileage because it really sucked gas not that I really cared and maybe there was detonation I couldn't hear over the exhaust so I'll pay better attention....and I really have to burn this gas up it's been in the tank since October treated of course but it's got to go.


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## Lemans guy (Oct 14, 2014)

You are doing great, yes racers do things that racers do. They do things to win racers to shave a quarter second off to respond when pedal is mashed to floor.

think about 1/4 mile drag strip the pedal is mashed down, total timing is what he needs...might as well have as much as the car will take idling and pick up the other 10 on the mash...

you can’t drive a street car like that.

2590RPM is really a fast ramp up and you can get detonation on acceleration. Not really needed. 3000 Rpm is fast in two as factory setting were offer 4200 to 4800.......for all of it....

3000 gives good street performance


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## Lemans guy (Oct 14, 2014)

The only change that you should make now is that 10 degree vac can set up....then drive it awhile and if all looks good you could bump the base up 2 degrees for 36 total......like I described previously!

good work enjoy it, you will see how good it runs now. And notice how strong it is with a light pedal.

try leaving a res light with a light pedal, it will take off, guys with bad timing are always having to mash the pedal to get enough advance to go...n


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## Baaad65 (Aug 29, 2019)

Sounds good, ya I'll look into the vacuum advance because if I bump the base up two degrees it puts my advance with the can at 27° to high like you said, just wish the MSD was 10° like described or I wouldn't have bought it.


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## PontiacJim (Dec 29, 2012)

Baaad65 said:


> Sounds good, ya I'll look into the vacuum advance because if I bump the base up two degrees it puts my advance with the can at 27° to high like you said, just wish the MSD was 10° like described or I wouldn't have bought it.


You can make a vacuum can stop/limiter which will do as the name says - limit the vacuum advance.

Photo shows a simple set-up using a piece of sheet metal. You may have to fit/trim to dial it in, but it'll work and looks to be simple.

You can weld/braze the slot the arm moves back and forth in, but you have to then grind/trim the welded/brazed section to dial in the advance.

Crane makes a kit you can add, but am not sure if it would work with your distributor. So do a search and you will see examples of vacuum advance limiters.


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## Lemans guy (Oct 14, 2014)

And just a note on that article from badass engines. The writer gives good info but he is talking about a race engine and he does not want to use vac advance, says he never does.

understandable, but the reason he only wants 10 in the distributor is he needs that other 26 degrees to idle smooth! And cool!

With no vac advance he cannot achieve that idle because he would bust over the 36 Total and basically destroy his engine.....

Street cars have the advantage of grabbing that additional timing from vacumn a great advantage, making the transition smooth and the timing coming in when needed for street performance.

Respect what racers do for the sport, they know their engines and have advanced motor sports for all. But everything they do you don’t necessarily want to do. As they have to give up a lot of drivability for speed. You on the other hand want a balance of both.

If you want total drivability get the mildest cam and a two barrel card and set timing to 1960’s factory specs.

If you want racing do what Badass says. If you want “Street performance and drivability, set it up like we are talking, plenty hot yet still drivable, efficient , responsive and cool!


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## Baaad65 (Aug 29, 2019)

I guess I didn't read it closely enough because I thought he was setting up a street/strip performance motor. Found an adjustable vac advance that looks identical to my MSD and says it's for GM points distributor 64-74 so I'm waiting on an answer.


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## Lemans guy (Oct 14, 2014)

Adjustable points cans only adjust the rate of vacumn and not the total timing. To fix the total timing at 10 you will have to do what I outlined ,or fabricate a stop like Pontiac Jim Said, or use an aftermarket set up like the crane. I have done them all, so you can decide how you want to do it. I have a stack of those adjustable cans under my distributor machines, always take them off and fix it certain for 10 degrees on the right vacumn.


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## Lemans guy (Oct 14, 2014)

He was setting up a street strip car, band you do it that way, you will just be leaning way more strip than street,...with no load sensing arrangement like the vac advance. And no advance timing at light throttle cruise. So you will be very retarded on timing at light throttle, consequently you will be very inefficient there, giving less power for the lean mixture that light throttle has.


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## Lemans guy (Oct 14, 2014)

Like that one you had was supposed to be 10 degrees but it is 14.....


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## Baaad65 (Aug 29, 2019)

He got back to me and says it will fit my distributor, 10° maximum advance and I can turn it down from there if I need...it's 15.00


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## Baaad65 (Aug 29, 2019)




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## PontiacJim (Dec 29, 2012)

Baaad65 said:


> View attachment 143082
> View attachment 143083



Note the description, "*allows for adjustment when the advance is activated*," not how much. You can give it a try to see how it works and go from there.


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## Baaad65 (Aug 29, 2019)

Ok here's what he wrote me.


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## Lemans guy (Oct 14, 2014)

Doesn’t the adjustable one you have supposed to give 10 degrees and it gives 14?

If you can make it give you 10 degrees at the right Vacumn it will work. However the ones see all pull way more than 10 degrees and the Allen head only adjust the rate of Vacumn not the total timing.

The B26 can and Lars corrector will do it for sure. This might, if you can get 10 degrees at the right vac

It works by turning down the rate of vac but that can be too high or too low so you have to adjust it right.

It can work, some guys make them work.


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## Lemans guy (Oct 14, 2014)

Most of the adjustable ones I see have 20 or more degrees of timing....that is 10 distributor Timing...

Crank timing is double distributor timing....

but he can give you one that stops at 5 degrees distributor or 10 at the crank at the right Vacumn it will work....I have a stack of those all new that don’t pull 10.....

But maybe his does


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## Baaad65 (Aug 29, 2019)

Don't think mine was adjustable because there were no directions on adjusting it or allen wrench, it's an MSD # 8463


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## Baaad65 (Aug 29, 2019)

His description says 10° but 20° at the crank so do I not want that?


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## Lemans guy (Oct 14, 2014)

No, the one I gave you back in the thread the B26 can with the Lars corrector will give you 10 degrees at the crank.....fixed


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## Baaad65 (Aug 29, 2019)

Ok, so you don't think I'll be able to dial this one down enough?


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## Lemans guy (Oct 14, 2014)

Like I said every MSD distributor I curve and every distributor I curve that has an adjustable can I take it off, new or not. They 20 plus degrees of timing way too much and what is adjustable is the RATE of Vacumn, through an Allen wrench fitting at the nose.

What he is saying is you can adjust the RATE and it will dial up more Vacumn or less and therefore will not be fully deployed.

You need to have a positive stop affixed to prevent the can from moving beyond 10 degrees at the crank. By the time you can maybe get a rate near that it likely won’t match your idle vac level and dither in and out. Constantly changing your timing.

I am not saying some guys can’t make it work paying enough careful attention and adjustment may get you close, but it is still not against a fixed stop. The arm of the can is hanging out midway if it is at 10 degrees crank. Why bother with all that?

I ditch put on the can that fits the vac for your idle, just below it as I described earlier, add the Lars corrector no adjustments, perfect timing. Yes it may be $30 and not $15 but your engine is worth it..


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## Baaad65 (Aug 29, 2019)

Got it, so can I use the Lars corrector on the advance I have? And I'll have to pull up a picture of it idk if it goes inside the distributor or not because I don't have alot of room even for the can I have.


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## Lemans guy (Oct 14, 2014)

I would not use the can you have I would get the B26 can, which I supplied the part numbers before. It will pull the vac at the correct rate with no adjustments. The Lars corrector will fit right on it. No adjustment needed, screw it on to the B26 Plug it in your Vac and timing will be perfect.

Now, will Lars corrector work on the adjustable can, yes it will knock the vac back, maybe you will get 10 degrees, but you will then have to adjust the rate of vac that the can pulls with an Allen wrench to get to a setting to where the B26 already is,...fixed and foolproof.

so can you do it, maybe. Like I said I hate those cans because I believe the Vacumn dithers, in and out, it would have a positive stop with Lars corrector.

It will be half baked to save $15 but you may get it to work. I can only tell you what I recommend and what I do for all the guys Corvette’s, GTO’s, 32 Fords, Chevy’s all,.......I always ditch the adjustable can

maybe it will work ok.


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## Lemans guy (Oct 14, 2014)

Lars corrector will fit on MSD distributors


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## Lemans guy (Oct 14, 2014)

But I don’t use it with the adjustable can, should still fit


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## Lemans guy (Oct 14, 2014)

But it may or may not knock it back to 10 degrees. The B26 can is the lowest timing can sold, it pulls 16 at the crank, and Lars corrects it to 10 degrees.

it is foolproof and reliable.


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## Baaad65 (Aug 29, 2019)

Alrighty, so finally got it out on the road, runs great without hearing any detonation lugging up an incline or letting off the gas or getting on it in fourth with the windows closed, hammered it from almost a dead stop a few times and it goes like an sob losing some traction and again in second, had to pedal it so I didn't look like Harrison Ford in American Graffiti upside down in the ditch on fire. Didn't really notice a difference from before all the adjustments but didn't even need the fan but it's only 60 here. So two things I noticed well three, still have the antifreeze smell for a little while in the cockpit, now when I'm idling after the drive I can't get the idle below 850-875 the screw is all the way out also while sitting in drive after I punched the throttle a couple times from idle and I have that slight hesitation, lastly the damn dipstick popped up a little with some leakage...thought I had that solved with the Wagner pcv and drilling out the breathers big time. I'll look into the can and stop you're recommending, thanks


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## Lemans guy (Oct 14, 2014)

Well one thing is timing is set first then carb ajusted so once you finish the timing set you go back on the mixture screws 850 or so sounds ok with what you are describing on the cam and engine. It won’t go to a factory idle spec if it is stroked and the cam is hotter...

hesitation from idle you may need to adjust some more transfer slot, acc pump etc..finish the timing first


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## Baaad65 (Aug 29, 2019)

Ok, I did get it to idle between 750 and 800 in the garage but seem to go up after the drive, did adjusted the idle mixture after this last timing adjustment also it didn't hesitate on the road so that's what counts not punching it in the garage. Also searched those part numbers for the B26 at O'Reilly's and Napa and nothing comes up so I'll keep looking.


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## Lemans guy (Oct 14, 2014)

Try Rock auto Standard Motor Parts VC 181


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## Lemans guy (Oct 14, 2014)

STANDARD MOTOR PRODUCTS VC181 Distributor Vacuum Advance | RockAuto


RockAuto ships auto parts and body parts from over 300 manufacturers to customers' doors worldwide, all at warehouse prices. Easy to use parts catalog.



www.rockauto.com





$10.49 on Rock Auto


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## Lemans guy (Oct 14, 2014)

You can dial the Wagner idle circuit up another half turn, from the turn and a half. So two turns out. Then reset the Wagner cruise circuit with the vacumn gauge. My engine needed 2 1/2 turns out on thee Wagner idle circuit to pull enough crankcase vac to be right.


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## PontiacJim (Dec 29, 2012)

Lemans guy said:


> STANDARD MOTOR PRODUCTS VC181 Distributor Vacuum Advance | RockAuto
> 
> 
> RockAuto ships auto parts and body parts from over 300 manufacturers to customers' doors worldwide, all at warehouse prices. Easy to use parts catalog.
> ...


I purchase a number of parts off Rock Auto for these older cars. Prices are great and shipping is really fast, so don't hesitate to order.


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## PontiacJim (Dec 29, 2012)

*Baaad65 - *"still have the antifreeze smell for a little while in the cockpit,

lastly the damn dipstick popped up a little with some leakage...thought I had that solved with the Wagner pcv and drilling out the breathers big time."

First issue may be a leaking heater core. It'll seep enough to be wet but not always drip, but once the engine temps get up, will evaporate the coolant and you get the smell inside the car. Others have had this experience - IF you still have the heater core intact.

Second issue is too much internal engine pressures as you know. Adjust the Wagner as *Lemans guy* stated. I have never used one so I can't comment on its use. I have read the directions online on how to adjust and you need the vacuum gauge to help with this.

Let's see a pic of the breathers and the "holes" you drilled. Some aftermarket valve covers do not have oil baffles or are located in a bad spot and the oil being slung around under the covers is thrown up and out the breathers. So you do need some kind of an oil baffle below the breathers to keep oil out. So take a look down into the hole the breather fits into.

PS - Losing traction is bad for tire life.


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## Baaad65 (Aug 29, 2019)

Ya the coolant smell started after I installed the 16lb cap so I'm sure the original core was on the verge, tha







t will be a bad job. I'll have a play with the pcv valve I guess. No baffles they were in the way of the rockers from the beginning, no oil out the breathers.


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## Baaad65 (Aug 29, 2019)

Car show today and it ran like a top, except for when it got stuck in second gear on the way there but that's another thread 👍


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## Baaad65 (Aug 29, 2019)




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## armyadarkness (Dec 7, 2020)

Stuck in 2nd gear, is usually time to zero your shifter linkage rods.


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## Baaad65 (Aug 29, 2019)

I did that when it got stuck two years ago and it was lined up then I thought the guy who aligned the front end last year checked it but maybe it goes out of alignment from time to time, I'll check it out 👍


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## Baaad65 (Aug 29, 2019)

....also changed the fluid this winter 🤔


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## BearGFR (Aug 25, 2008)

There's definitely some adjustment involved. The first GTO I ever drove (long story there) was a '65 4 speed and its shifter was "off" by quite a bit. You had to sort of 'zig zag' it through neutral on the way to 3rd from 2nd, and if you didn't do it right the shifter would hang up and get very difficult to move.

Bear


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## Baaad65 (Aug 29, 2019)

I'll check out out this week 👍


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## armyadarkness (Dec 7, 2020)

BearGFR said:


> There's definitely some adjustment involved. The first GTO I ever drove (long story there) was a '65 4 speed and its shifter was "off" by quite a bit. You had to sort of 'zig zag' it through neutral on the way to 3rd from 2nd, and if you didn't do it right the shifter would hang up and get very difficult to move.
> 
> Bear


Ive had to crawl under and "un jam" several muncies, over the decades. It's strong incentive for bronze bushings. Also, many guys seem to like zeroing it, without the pin in the shifter... and then you only get it "close".


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## Baaad65 (Aug 29, 2019)

Got bronze bushings, I do have the zero tool so I'll check it out...funny both times it stuck I was making a nice slow and easy shift never had issues when I'm really gear jamming.


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## armyadarkness (Dec 7, 2020)

Baaad65 said:


> Got bronze bushings, I do have the zero tool so I'll check it out...funny both times it stuck I was making a nice slow and easy shift never had issues when I'm really gear jamming.


Same here. Muncies don't seem to like lazy shifting.


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## Baaad65 (Aug 29, 2019)

Ok got the B26 vac advance ordered from Rockauto now I have to contact Lars about the stop.


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## Baaad65 (Aug 29, 2019)

So after I got the B26 ordered I talked to Henry who I guess is Lars's partner and he said the advance stop is a royal pain to install on the MSD distributor I have, you have to pull it apart and drill something out and he wasn't to concerned about the 14 degrees I'm getting out of my vac can, so I might look into that Crane advance with a stop and install the B26 and see what that pulls otherwise I'm going to leave it alone and just run with 25 degrees of idle advance, 23 mechanical 11 at the crank for 34 total, maybe I'll try 13 at the crank for 36 total but my idle advance will be 27....it ran great on Sunday.


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## Lemans guy (Oct 14, 2014)

Well you got a few ways to go there, and since you are running good with no starter kickback, you should be ok. There is a bit of light work to put the can and corrector on the MSD but not that bad. Nevertheless you are not at a bad place now.


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## Baaad65 (Aug 29, 2019)

So what is the B26 VC181 advance going to be lower or higher than my 14° can I can't remember, maybe it will save me from installing it and can maybe return it. I contacted MSD and they're looking into what I could do, and the guy Henry said MSD has a proto type with the stop but it will be a while yet. It's going to be 90 this weekend so maybe I'll bump the timing to 13° and if it runs hot, good test.


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## Lemans guy (Oct 14, 2014)

Yes the B26 can pulls 8 degrees distributor 16 degrees at the crank. So if you are not going to install it with the corrector to bring it to 10 leave the MSD on at 14. 14 would be better than 16.

You have good numbers now, and you can tell by driving it. 10 vacumn is the perfect set up normally. So I always shoot for that. But 14 is good and better than most out there running.

I have set up many with 18 +18 base and 10 vacumn giving 28 idle vac. Your cam is lively and can take it, so as long as you are not kicking back on starting or pinging you are ok.

The advantage of the lower vac also gives you more room to move up the base to 36 or 38 witout driving the idle timing back up too high.

You are pretty good, so drive it and enjoy it. You can always put in the B26 and corrector on later or wait for the MSD improvement to 10 degrees Vacumn. I would note that even MSD knows that is an important improvement.

Timing is always a range, so there is some slop in it, and it goes with each particular engine combo. If you go over a little, the best place to do that is on vacumn advance and not total timing.

I think you have done a great job sticking with it all, enjoy the ride!


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## Baaad65 (Aug 29, 2019)

Sounds good and that's what I'm going to do also opened up the pcv valve to 2.5 turns, going to check the idle mixture again and get some fresh fuel in it this weekend..first cruise night this Friday right by my work 👍 thanks again to everyone who helped me out and hopefully it didn't cause anyone to want to start sniffing glue 🥴


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## Lemans guy (Oct 14, 2014)

Try a bottle of that Redline S1 in the fuel tank when you you fill up with fresh summer blend gas.....have a nice cruise in!


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## Baaad65 (Aug 29, 2019)

I bought a bottle of that Techtron ? so I'll use that up first....also something cool I talked to MSD and their engineers are working on a prototype advance stop for the MSD vac advance can that was 3D printed so they are sending me one for free so we'll see how and if it works


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## Lemans guy (Oct 14, 2014)

Great take some photos and share it with the gang. Limiting with a stop is the key!.....If you can, set it for 10 degrees, set the vacumn 2 or 3 degrees below idle vac, and hook to full manifold. Let’s see what they produce.


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## Baaad65 (Aug 29, 2019)

Will do


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## Baaad65 (Aug 29, 2019)

Lemans guy said:


> Try a bottle of that Redline S1 in the fuel tank when you you fill up with fresh summer blend gas.....have a nice cruise in!


Sorry it was Star Tron I'm using not Techtron got my Trons mixed up, hope that's ok to use?


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## Lemans guy (Oct 14, 2014)

Different...Star-Tron is a stabilizer like Sta-bil,....Techron is a cleaner that will withstand the heat of combustion and clean fuel system.


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## Baaad65 (Aug 29, 2019)

So I'm thinking save the Star Tron for last fill up before winter and use the Redline now?


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## Lemans guy (Oct 14, 2014)

Yes


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## Baaad65 (Aug 29, 2019)

So bumped the base timing to 13° mechanical all in at 36° @ about 2900 plugged in the vac advance and I get 27° so we'll see how this does in the heat tomorrow, filling up with some fresh 93 octane and Redline S1....also change the oil and filter went with the Rotella 15W40...no clicky clicky anymore when cold 👍 also checked the shifter alignment and the tool slips right in...I guess no more Mr. Niceguy shifting 🤨
p.s. MSD advance stop prototype is in the mail.


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## Lemans guy (Oct 14, 2014)

You are hiring on all cylinders now! Should run real strong and cool.


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## Lemans guy (Oct 14, 2014)

Remember try a light pedal from a full stop and see how responsive it is...


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## Baaad65 (Aug 29, 2019)

Car ran great for the cruise show, 25 miles with some stop and go traffic at 90 degrees outside temp maxed out at 210 but that's with all three fans going and if I would've been stuck in traffic longer I think the temp would have climbed, leaked a little bit out of the overflow can when we parked, never heard any detonation though, maybe I should set it back to 11° base when it's that hot if it will help keep the temp down. Filled up with fresh 93 and Redline fuel treatment.


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## Lemans guy (Oct 14, 2014)

you can, but at those either of those settings your timing will not make it run hot. Does your system need a Flush? see my posting on fushing cooling system, Bear made it a sticky. rust inhibits cooling and it don"t take much.


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## Baaad65 (Aug 29, 2019)

Idk I've had to drain the radiator several times for different reasons, and this is only the third summer on this motor and radiator, running 70/30 water to antifreeze with two bottles of water wetter which is supposed to have rust inhibitors, new Flow Kooler pump two years ago, drilled 160 stat, large two core aluminum radiator, one 16" puller fan 2600 cfm, two 13" pusher fans 1000 cfm each...idk what else I can do but it's better than last year and heck it was at least 90 ° on the way there so maybe that's as good as it gets, nice and cool on the way home at night.


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## Lemans guy (Oct 14, 2014)

You got it covered! Maybe a nice new radiator cap.


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## Baaad65 (Aug 29, 2019)

Just got a nice 16lb one.


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## Lemans guy (Oct 14, 2014)

Yeah, I would just drive it and watch it...


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## Baaad65 (Aug 29, 2019)

Well I got the MSD vacuum advance limiter today, it's not 3D printed so maybe it's an actual part they're going to start producing...I'll try to get it installed this week 👍


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## Lemans guy (Oct 14, 2014)

Looks like it will work, gonna have to try and get it right before you locative it in...


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## Lemans guy (Oct 14, 2014)

Sorry, ..loctite....it in


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## armyadarkness (Dec 7, 2020)

Lemans guy said:


> Looks like it will work, gonna have to try and get it right before you locative it in...


I have the same dizzy and I ordered mine from Lars. It hasnt come yet, but I'm curious as to why MSD says it's a pain.

I sure can see that setting theirs would suck... Itll have to be disassembled, "ball parked", reassembled, tested, adjusted, reassembled, disassembled, loctited. I would have plenty of beer and patience.


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## Lemans guy (Oct 14, 2014)

Lars corrector goes right on top of the vacumn can, instructions included. They don’t vary much it will pull 10 degrees, sometimes I get one that pulls 8 or 12...you can leave it there, or just a slight bend on the vertices stem of the vac can, imperceptible really. Just take the vac can off and do it with a pliers gently.

that looks to work, but how much adjustment is needed we can’t tell yet. Baad will let us know!


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## armyadarkness (Dec 7, 2020)

That's interesting. Baad indicated that MSDsaid their dizzy required modifications for the stop, so I'm anxious to get the parts all together. When does the 181 pull full vacuum? I had it saved, but we hit 9 pages... lol.


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## Lemans guy (Oct 14, 2014)

So the B26 or VC 181 will start to pull timing at 5 to 7hg and will pull a full 8 degrees distributor ( which is 16 degrees at the crank) at 11 to 13hg.

Lars corrector will shorten the length of the pull and knock the timing back to 10 degrees, but it also drops that vacumn some as well, since it does not have to pull as far it reaches the full stop a bit lower on the vac.

as long as your idle vacumn is above that 11 to 13hg you are good. Even lower really as the corrector will drop that to maybe 9 or 10hg. The way to tell is disconnect vac and plug read base timing. Then reconnect to full vac and read idle timing, should increase by 10 degrees.


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## armyadarkness (Dec 7, 2020)

Im excited to get it all installed. Jersey weather was mid 90's and pure humidity, all weekend long. I did several car shows, cruises, and explorations, totaling at least 100 miles, each day, in the heat of the day.


Exhaust crossover not blocked.
Cold Case aluminum, two core radiator.
Flow Cooler iron pump (old style).
Drilled t stat.
No radiator reservoir.
No inner fender debris flaps.
No radiator seals.
No fuel return.
The car between 160 and 180 all day, climbing to 200 when sitting. After sitting or low speed cruising, full throttle use just caused it to bog and sputter, but, it cleared up if you stayed in it, which leads me to believe that it's hot fuel.

In any event, I have room for improvement now.


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## Baaad65 (Aug 29, 2019)

armyadarkness said:


> I have the same dizzy and I ordered mine from Lars. It hasnt come yet, but I'm curious as to why MSD says it's a pain.
> 
> I sure can see that setting theirs would suck... Itll have to be disassembled, "ball parked", reassembled, tested, adjusted, reassembled, disassembled, loctited. I would have plenty of beer and patience.


Lars said installing there stop on an MSD involed some work.


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## Baaad65 (Aug 29, 2019)

Also if this works I'll have a B26 for sale cheap...Rock auto wants 4.50 to send it back, the thing was only 20.00...maybe I'll use it as a Christmas tree ornament 😁


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## armyadarkness (Dec 7, 2020)

Baaad65 said:


> Also if this works I'll have a B26 for sale cheap...Rock auto wants 4.50 to send it back, the thing was only 20.00...maybe I'll use it as a Christmas tree ornament 😁


Why didnt you put the B26 on yours? You kept the MSD adjustable?


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## Baaad65 (Aug 29, 2019)

Because Lars wanted another 15.00 for their stop and he said it was a pain to install on my MSD can which is not adjustable I tried some allen wrenches up it's hole, so MSD sent me this stop for free and looks easy enough to install I hope so we'll see if it works and I'm going to report back to them. I had already ordered the B26 when I found out about the stop being difficult from Lars but I have it if I need it.


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## armyadarkness (Dec 7, 2020)

Baaad65 said:


> Because Lars wanted another 15.00 for their stop and he said it was a pain to install on my MSD can which is not adjustable I tried some allen wrenches up it's hole, so MSD sent me this stop for free and looks easy enough to install I hope so we'll see if it works and I'm going to report back to them. I had already ordered the B26 when I found out about the stop being difficult from Lars but I have it if I need it.


Are you sure that yours isnt adjustable? Ive seen a few people think that, when they were just using the wrong wrench! There's no positive stop on the adjustable cans... The wrench passes through the adjustment screw (like a donut), so if you dont use a big enough wrench, it wont engage the adjuster.

I only mention this because I was fairly sure that Holley made "only" the adjustable type.

Man... You have to LOVE Holley... Under specs, they tell you everything that you would never need to know, and nothing that you do. So... yeah. I can tell you what color socks that the CEO wears, but not how many degrees the can pulls, or when.


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## Lemans guy (Oct 14, 2014)

I think you said that Henry said it was hard to do on MSD distributors. Well it is easier on stock ones, but not that hard on the MSD. You need to do it on the bench, but I do all of them on the bench.
Take off the cap and rotor, remove the roll pin on the lower gear, mark it so you put back on the same way with the shims in the correct place also.

Now slide the gear up a bit for access to the snap ring under the breaker plate, remove that.

Then gently pry the the breaker plate to get the vacumn advance rod free. I usually push down with a screwdriver on the rod pushing it thru the big square hole, you have to twist it a bit and pull it toward you as well. Just be gentle it will come out.

On some I have to trim the bottom plastic bushing that the VC rod goes thru so it all clears, just file on the plastic so it stick.

then use a vac pump on the nipple to pull the rod and install the screws thru the corrector and VAC.

press the plate down reinstall the snap ring, put the gear back and install the roll pin.

Most roll pins are not welded in, what Henry may mean is if it is that little weld, very small has to be ground off to knock the roll pin out.

Most distributors don’t welded or braised in roll pins on the lower gear. Most I see are just held in with a roll pin. MSD may be-doing it more now, not sure, but it is not a big deal.

Use the hand vacumn pump to advance the VAC for access to the screws that hold it on. And don’t forget to replace any ground wires that may have been on those screws.

Lars will have instructions with his corrector. Yes some can be done without removing the distributor from the engine. But I take em out and just Re drop em. Cause I put them on the Distributor Machines and with it on the bench you get it right easier.

The MSD stop will work I am sure, they should just build the cans with a reduced hole to pull no more than 10 degrees....more is not needed or desired.


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## Baaad65 (Aug 29, 2019)

armyadarkness said:


> Are you sure that yours isnt adjustable? Ive seen a few people think that, when they were just using the wrong wrench! There's no positive stop on the adjustable cans... The wrench passes through the adjustment screw (like a donut), so if you dont use a big enough wrench, it wont engage the adjuster.
> 
> I only mention this because I was fairly sure that Holley made "only" the adjustable type.
> 
> ...


Well I tried all kinds of sizes that would fit in the hole and kept turning them and nothing happened, MSD said it wasn't adjustable.


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## Lemans guy (Oct 14, 2014)

It’s an adjustable non adjustable.


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## Baaad65 (Aug 29, 2019)

This is my point, your description of steps don't even fit on my computer screen without scrolling so I'm trying the one they sent me and hope for the best but appreciate all the help


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## Lemans guy (Oct 14, 2014)

Ha yes, sure understand, the end result is what matters. The MSD one looks like it will work. And you are running good now Thai will only make it better.


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## armyadarkness (Dec 7, 2020)

Lemans guy said:


> I think you said that Henry said it was hard to do on MSD distributors. Well it is easier on stock ones, but not that hard on the MSD. You need to do it on the bench, but I do all of them on the bench.
> Take off the cap and rotor, remove the roll pin on the lower gear, mark it so you put back on the same way with the shims in the correct place also.
> 
> Now slide the gear up a bit for access to the snap ring under the breaker plate, remove that.
> ...


Holy Cow! That's terrible! If that's what I need to do on my Summit dizzy, then I wont be doing it any time soon.


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## armyadarkness (Dec 7, 2020)

Baaad65 said:


> Well I tried all kinds of sizes that would fit in the hole and kept turning them and nothing happened, MSD said it wasn't adjustable.


If they told you that it wasnt, then yes, I wouldnt even be trying.


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## armyadarkness (Dec 7, 2020)

I received the timing corrector from Lars yesterday, and sure enough, installation on an MSD is involved. If it's the right thing to do, then I'll do it, but it's definitely going to be on hold. I still have other issues and I'm not looking to take on such a big endeavor, until I cross off a few other items.

And... I havent swapped a dizzy in an out, without screwing it up, in 35 years!


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## Lemans guy (Oct 14, 2014)

Yeah, you want to take your time if you decide to do it.


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## armyadarkness (Dec 7, 2020)

Lemans guy said:


> Yeah, you want to take your time if you decide to do it.


I will do it, just need a clear mind and a day with no humidity.


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## Baaad65 (Aug 29, 2019)

That will be in October......the no humidity part


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## michaelfind (Dec 14, 2018)

I'm not trying to hijack but want to ask about my similar timing concerns. I think this is exactly in line with what has been discussed here for several pages. Ya'll may have even answered this and I missed it. I'm running 17 initial timing without vacuum advance, 33 at idle with vacuum advance all in, then 34 total by 3,000 rpm. So, yes, I've got the dreaded 16 degrees of vacuum advance. However, I'm not hearing any pinging and I don't see any shiny specks on my plugs. What benefits am I missing by not using the Lars VAC? I already have one but have postponed installing it for all the reasons listed above. Plus, I wonder if I might idle hotter in the summer with my vacuum advance limited to just 10.


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## armyadarkness (Dec 7, 2020)

Youre not alone. I have a VERY similar situation... I feel like my performance is down a bit, but my timing is set high, in all areas, and I have no ping. Seriously makes me wonder if the balancer slipped.


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## michaelfind (Dec 14, 2018)

armyadarkness said:


> Youre not alone. I have a VERY similar situation... I feel like my performance is down a bit, but my timing is set high, in all areas, and I have no ping. Seriously makes me wonder if the balancer slipped.


I've not been to the drag strip yet, but I feel like mine is running strong. This is a fairly fresh build with a new balancer so I think my numbers are correct. Now, on top of that, I found this old post from Lars in 2007 that still said up to 16 vacuum advance was OK. GTO Tuning and Setup Tips Maybe fuel has changed enough since then to make 10 from vacuum advance the best number today. I think what I may do is keep my current setup with the Pertronix distributor as is, then put the VAC limiter in my original distributor (much simpler to do apparently) then check them back to back. That is IF I can find a free Friday afternoon/evening and it's not raining, and the drag strip is open for test and tune...
And again, not to hijack, but for full information. This is a recently built 467 stroker with 6X heads and the XE 274 cam, so not stock internals at all.


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## Lemans guy (Oct 14, 2014)

Yes Lars has revised that number, based on research with the new gasoline. That is why he developed the corrector. 10 is perfect on vac advance for idle and cruise. 8 to 12, ok.

17 is really too much. Maybe you are not pinging on acceleration, but dropping out real fast from WOT adds 17 degrees to timing real fast as well. Better to have it at 10 degrees.

l have set up lot’s with 18 base + 18 Centrifigal + 10 vacumn.......28 idle vac and 46 at light throttle cruise. If you have a stout cam it can take 28 at idle. Most don’t need that much to run cool. Low to Mid 20’s I usually shoot for......unless the cam is real hot then high

Like 24 Centrifigal, 12 base and 10 vac.....that’s 36 total and 22 idle with full manifold vac.

3000 RPM all in is a good number. Corvettes go lower. The problem getting lower is not allowing the springs to bring in Centrifugal timing at idle.

lighter springs do that.

You have done a great job on your timing, I would stick with it and finish it just perfect with that vacumn corrector. You have a transition point on acceleration where your vac timing is still in and your Centrifigal is adding timing.....that could get pretty high with your current numbers, and it really is not giving you better performance or cooling.


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## Lemans guy (Oct 14, 2014)

Remember that timing can be both too far advanced for optimal running or too retarded for optimal running. This is some swag and each engine combo is different. The guys like Bear, Pontiac Jim and Big D, LA Tech, 052, Pontic, blkjudge stay tuned in to their engines. And get a feel for what what is right as well.

if you can get a good feel and the numbers are right then you are spot on, and have perfect timing. Not saying that can’t run like you are you are just pushing the edges of the sweet spot.

if tuning yours I would up that Centrifigal to 22 and set your base at 14 with then 10 vac for 24 Idle timing and stay with all in @3000 RPM. But that would allow a setting of 36 total where yours is 34......

upping to 36 now would push your idle timing to 35, really not needed and could cause kickback and pinging on acceleration.

Remember you guys are in a good spot, we are fine tuning here. Gonna do a 63 split window corvette and a 61 corvette next week,...bet they will have 50 to 60 degrees of timing when all totaled up, and all at the wrong times and places!


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## michaelfind (Dec 14, 2018)

Lemans guy said:


> Yes Lars has revised that number, based on research with the new gasoline. That is why he developed the corrector. 10 is perfect on vac advance for idle and cruise. 8 to 12, ok.
> 
> 17 is really too much. Maybe you are not pinging on acceleration, but dropping out real fast from WOT adds 17 degrees to timing real fast as well. Better to have it at 10 degrees.
> 
> ...


Thank you. That is what I was needing to learn.


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## Baaad65 (Aug 29, 2019)

Ok got the MSD vacuum advance limiter installed in about 5 minutes, set it in the middle so the advance plate moves about half of what it can move...it was 85° in the garage at 8pm with a fan and I had had enough heat for the day so I'll time it up another night.


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## Lemans guy (Oct 14, 2014)

Good work! And have to salute MSD engineers for going the extra mile and engineering this stop.

All the Holley Companies have contributed so much to motor sports historically, MSD, Accel, Quick Fuel, Mr. Gasket, B&M, Earl’s fittings, Flowmaster, Hooker, Hurst, Mallory and Tremec and many more!

So great job MSD engineers. Now go the extra mile and make vacumn cans for both diameter distributors. Points and HEI that as manufactured only pulls 10 at the crank, with no stops needed and has adjustability for RATE of vacumn.....and will fit original and MSD distributors. ......maybe someday.

If anyone can do it it is MSD.


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## Baaad65 (Aug 29, 2019)

Ok got to setting the vacuum stop, took a couple tries but I have base set at 13° plug in the can and I get 23° which if I subtracted right is 10° 😁 idling at 780rpm, 23° bushing +13° base =36°, only thing I noticed now is the 36° is all in around 2500 rpm so is that ok or should I try a stiffer spring...don't know how that changed it used to be around 3000 rpms.


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## Lemans guy (Oct 14, 2014)

Numbers are good, I would yes try a little stiffer spring, a medium one and see if you get closer to 3000 Rpm


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## Lemans guy (Oct 14, 2014)

The 23 degree bushing is thicker than an 18 degree bushing so it limits the travel.....therefore the springs bring it to the end point sorry “all in” sooner....


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## Baaad65 (Aug 29, 2019)

Ya but I had it all in at about 3000 rpm with the 23° bushing before 🤔


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## Lemans guy (Oct 14, 2014)

Sorry I explained that confusingly, the thicker bushing, limits travel and therefore reduces the amount of Centrifigal timing.........


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## Lemans guy (Oct 14, 2014)

Was the base the same or was it 34? ...every change has some effect on the whole


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## Lemans guy (Oct 14, 2014)

Remember to verify the 23 bushing with your light.....they sometimes vary


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## Lemans guy (Oct 14, 2014)

Of course your all in is with vac disconnected and plugged....


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## Baaad65 (Aug 29, 2019)

The last time I checked it was at 36°, I bumped base from 11 to 13 and I did unplug the can and cap the port...so how do I verify the 23° bushing, don't think that was covered here yet or I missed that day of class.


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## Lemans guy (Oct 14, 2014)

Parking brake on tires chocked, car in park or neutral

So remove one spring from the distributor. Then replace the rotor and cap.

then plug the vacumn to the vac can and start her up. Or start it and then plug vac can.

now with your timing light rev up the throttle by hand,......watch the timing light.

because you removed one spring the weights will reach total advance very fast, so you won’t have to over rev the engine.

what you are looking for is when the timing STOPS advancing, it will reach a level where it goes no further, even when revved higher., note this number.

Then subtract what your base setting was, and you will have the Centrifigal advance number.

it should be 23, maybe it will or it could be 25 or 21. Just note it and then you can set an accurate base timing and total timing number.

Don’t forget to replace the spring that you removed.


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## Baaad65 (Aug 29, 2019)

Ok, do I have to set the dial back light to any certain degree? and when you say not advancing anymore are the zeros going to be lined up on the balancer or doesn't it matter it just stops advancing period?


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## Lemans guy (Oct 14, 2014)

You can set it for 36 or higher, try 40, the light will read the timing and the mark will be on zero....you read the advance on the light the balancer is at 

it will stop advancing at some number, note that......


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## Lemans guy (Oct 14, 2014)

Balancer is at zero....when light is reading the advance


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## Baaad65 (Aug 29, 2019)

So where should I see the 23° to make sure the bushing is accurate on the balancer, the number you said to take note of because idk if I'm understanding this correctly.


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## Lemans guy (Oct 14, 2014)

You won’t see 23, because your base is 13......so you will see whatever your base is - wherever it stops advancing.....to give you the 23 or Centrifigal advance..

let’s use 10 base,...you set the timing light up at 36 you rev it up spring removed and it stays on zero until 36 but then the timing mark moves to 2 degrees and no more change.

so now reset your light to 38 and verify...do it again now it stops at 38 mark stays on zero, no more change.

subtract 10 base from 38 and your bushing is giving you 28 degrees of Centrifigal advance.

you can just set the light up a little higher like 40 and it will read it up and stop likely before that.


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## Baaad65 (Aug 29, 2019)

Ok think I get it, how often is the bushing not accurate? and I still don't know why I had 36 total degrees at 3000 rpms with the 23 bushing before I messed with the vacuum advance which should have no bearing on mechanical advance. Think I'll try one heavier spring first to get my all in at 3000.


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## armyadarkness (Dec 7, 2020)

I can tell you that I set my dizzy up, to spec, and the total and can were both off several degrees.


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## Lemans guy (Oct 14, 2014)

You are right bad, same bushing should yield same travel distance, changing the bushing will alter the amount of timing. And vac advance should not have effected that.

Just change that spring and see what you get. You are real good with these numbers.

Sometimes those bushings are spot on and sometimes not, it has been a mixed bag, but it is a very good system that MSD made there and they are not off by that much.


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## Baaad65 (Aug 29, 2019)

Sounds like a plan, and MSD said they eventually will make this part available


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## armyadarkness (Dec 7, 2020)

You should post your findings for the part, here. Who you called and what your procedure was for obtaining the part from MSD. We get a lot of timing inquiries and many users have the MSD. It'll save some serious agg for the next guy!


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## Lemans guy (Oct 14, 2014)

I don’t know how you got that 2500, could you have forgot to unhook the vac advance when testing for it,...because that would do it for sure.....it keeps a lot of timing in.....


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## Baaad65 (Aug 29, 2019)

I actually saw a limiter for an HEI on Ebay from MSD and asked if it worked for my distributor and it wouldn't so I explained the situation that's when they helped me out with this proto type, I was getting help from Daniel, they were super helpful but I did all my messaging through Ebay.


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## Baaad65 (Aug 29, 2019)

Lemans guy said:


> I don’t know how you got that 2500, could you have forgot to unhook the vac advance when testing for it,...because that would do it for sure.....it keeps a lot of timing in.....


I almost forgot to unplug it but then remembered so that's not it, idk what happened.


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## Baaad65 (Aug 29, 2019)

Ok pending something not feeling right on driving it this is how it's set, changed to two light blue springs (even though they're really medium blue and the only blue ones in the kit) base advance is at 12° plug the can in and I have 22° at idle, 23° green bushing + 12° = 35° all in at 3000 rpms...no hesitation when I mash the go pedal from idle which is about 780 rpm so we'll see how it works 👍


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## Lemans guy (Oct 14, 2014)

Good work….should run cool and smooth…

try a light pedal from a stop should feel pretty good…!!!

good all around…


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## Lemans guy (Oct 14, 2014)

And if you want 36 just turn the base up one to 13…

and you won’t have to change anything else…

always listen for pinging, if you here dial base back 2 degrees… and retest..


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## Baaad65 (Aug 29, 2019)

I thought the last time I set the base at 13° but now it's at 12°, so 13° would put the idle advance at 23° so that's still ok? and I didn't have time to take it for a drive so it will be interesting to see if it feels any different with the new springs when I get into the pedal.


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## Lemans guy (Oct 14, 2014)

Yes 23 at idle is ok and 36 Total is where I start them all.


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## Baaad65 (Aug 29, 2019)

Ok got her out for a drive but first set the base back to 13°, 23° on the can at idle, felt good with no detonation lugging in fourth up a slight grade. Went about 15 miles with only a few stops about 75° outside and still is running 180° with the puller fan on so when it's 85 out and I get in traffic I know it's going to be around 200° so I guess without the vacuum advance it would be running hotter so hopefully it's helping. Did a couple of shift light runs and it feels like a beast only problem and I know this isn't the right thread but the dipstick was up a little and a bit of oil came out, idk what the problem is I have good flowing breathers and a 130.00 pcv valve so the spring went back on the dipstick to avoid a mess...frustrating.


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## Baaad65 (Aug 29, 2019)

Also since we're talking tuning just thought I would check the plugs after all my additions and adjustments and test drive so how do they look not too lean? After my drive it idled a quick minute while you opened the door so do you really have to be cruising along and shut the car off and coast somewhere and pull a hot plug to get an accurate read? These are NGK iridium IX BR6FIX one step colder than stock gapped at .







38


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## PontiacJim (Dec 29, 2012)

Baaad65 said:


> Also since we're talking tuning just thought I would check the plugs after all my additions and adjustments and test drive so how do they look not too lean? After my drive it idled a quick minute while you opened the door so do you really have to be cruising along and shut the car off and coast somewhere and pull a hot plug to get an accurate read? These are NGK iridium IX BR6FIX one step colder than stock gapped at .
> View attachment 143460
> 38
> View attachment 143461
> View attachment 143462



It may be my computer, but in the pics I see 2 white flecs on the center just below the electrode. Get a magnafying glass and look closely - you do not want any aluminum flecs/specs as that is an indication of detonation/too lean. If it is, then drop total down 2 degrees to 34 and check again. The plugs don't look too bad in my opinion, but examine the porcelan in the center nose.


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## Baaad65 (Aug 29, 2019)

No I see them too blowing up the picture, this was # 1 plug and I haven't had them out in a while so idk when it occurred, I'll check the rest...primary jets are 74 and secondarys are 82...like I said I didn't hear any pinging lugging it with the windows closed so idk.


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## Lemans guy (Oct 14, 2014)

Agree with PJ to check for the specks, but you were running with way advanced timing before you got this all dialed in, so it could be from then if it is specks.

Take some photos and check em again.

On the dipstick turn your Wagner valve out 2 1/2 full turns on the idle circuit, reset the cruise circuit with vacumn gauge and reinstall. The original setting of 1 1/2 turns out on these big engines is just a starting place. You can get it right


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## Baaad65 (Aug 29, 2019)

I'll clean up the plugs and then try another drive and inspect, I do have the valve open at 2.5 turns but I didn't check with the vacuum gauge as it's a pain with the short hose to the carb so I probably should do it right.


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## Baaad65 (Aug 29, 2019)

Think I need to richen up the jets or are they light in color from to much advance? And is the best way to get an accurate read on the plugs is to use the procedure I described ? I went down one step colder incase of detonation and my higher running temp last year so is that not a good idea?


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## PontiacJim (Dec 29, 2012)

Baaad65 said:


> Think I need to richen up the jets or are they light in color from to much advance? And is the best way to get an accurate read on the plugs is to use the procedure I described ? I went down one step colder incase of detonation and my higher running temp last year so is that not a good idea?


That gap looks a bit too wide in my opinion.

Check out these pics. Look at the second photo of the plug - looks like yours. Rich on idle, lean at WOT. Then look at the strap heat marks which are also explained. Further down explains how to test.





__





FBO Ignition - Home of the HRR688 - Spark Plug Reading







www.4secondsflat.com


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## Baaad65 (Aug 29, 2019)

What a great site that is so much information on tuning everything, I can't believe he can tell so much from a plug and I'll be sending him some pictures of mine and hopefully I haven't damaged my pistons. I measured that one at .38 so not to far off from what they call for my bigger concern is what he says about the little diamond spots on my plug, not good so I have some things to figure out. Thanks for sharing that site 👍


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## armyadarkness (Dec 7, 2020)

FYI, I wouldn't be "mechanically" fastening your dipstick. Frustrating? Yes, but not nearly as frustrating as blowing out the rear seal or oil pan gasket. That pressure needs to go somewhere, the dipstick is the lesser of the evils, until you get this sert right. You likely just need to reset the valve. Sounds like you dont have it right. The gauge should jump when you hit the mark.


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## Lemans guy (Oct 14, 2014)

Right if did not set the cruise circuit on the Wagner it will not pull the vacumn correctly. So try that first.
Reading plugs is good an AFR Gauge is even better with a wide band oxygen sensor, you can have an exact reading and see where you are at idle, cruise and WOT.


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## Lemans guy (Oct 14, 2014)

And yes that is a great site PJ recommends I have their book “tuning to win”


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## Baaad65 (Aug 29, 2019)

armyadarkness said:


> FYI, I wouldn't be "mechanically" fastening your dipstick. Frustrating? Yes, but not nearly as frustrating as blowing out the rear seal or oil pan gasket. That pressure needs to go somewhere, the dipstick is the lesser of the evils, until you get this sert right. You likely just need to reset the valve. Sounds like you dont have it right. The gauge should jump when you hit the mark.


I know it's not the right thing to do, guess I just won't do any WOT driving and I did have it adjusted right where the needle jumped then later I opened it up to 2.5 turns but didn't put the gauge on it, just being lazy I guess.


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## Baaad65 (Aug 29, 2019)

Think I'll clean up the plugs and put my base back to 11° -34° total and read the plugs from there, thought the carb was jetted rich enough and so did the guy who built it. You think lower timing would help the lean condition? Also before I wasn't to advanced as I had base at 19° but an 18° bushing so 37° total and no vacuum advance.


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## Lemans guy (Oct 14, 2014)

Yes but you also had 16 degrees Vacumn on top of the 19 at base….so that is 35 degrees.

Now that is at high vac and more closed throttle but as you accelerate the vac timing comes down and your centrifugal timing is coming up so you can get too much timing on acceleration….not just at WOT

so maybe you had some there, yes try 34 like PJ said, listen and recheck the plugs….even put in a new set of plugs….for really seeing-the new clear picture….


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## Lemans guy (Oct 14, 2014)

When you had 37 total and no Vac advance may have been just barely high…especially if you were hammering it a lot…..


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## Baaad65 (Aug 29, 2019)

Ok, vac can was only pulling 14 degrees but I'll make the adjustments...so can the higher advance cause the lean condition or is it a carb issue or maybe both? also cleaned out the exhaust tips to monitor them and they're still pretty clean after my drive. What's your thought on the colder plug, I tried it incase of detonation and my high running temp last year so I still have the ones I took out which don't look bad they are NGK v power YR5


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## Lemans guy (Oct 14, 2014)

No the advance is not causing the lean condition in any measurable way. That is a result of carb adjustments and jetting.

on NGK plugs lower number is a hotter plug, I run NGK V-Power R5670-6 stock # 2746

Butler had recommended these and I like them. I would drop a heat range from those NGK 5’s and go to these six. Butler will ship em to you if you want.

Plugs are a cost but, detonation is much worse. I think the colder plug, your much better timing set up, running a conservative 34 total as PJ recommended and tuning in your carb should get you right.

Note that in the web that PJ recommended that racers goes on to say he recommends using a wide band 02 sensor (WEGO) to get AFR’s right. So sometime you could go there. A shop that can do a portable test or your own installed AFR meter.

in the meantime use traditional methods for carb dial in.....and high octane gas!

good work


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## Baaad65 (Aug 29, 2019)

The NGK 5's were in the motor from Butler so last year I went with the NGK Iridium BR6FIX which were supposed to be one step colder, I'll clean up these plugs gap them to .35 set the timing back to 34 and dial in the pcv and watch things and I always run 93 octane, maybe I'll have to richen up the secondary's I think I have some 84 jets to replace the 82's. Also maybe I should talk to someone at that tuning site and buy the book, reminds me of my YZ125 beating up on my friends KZ250 for a bit because I was running lean but it was short lived and didn't end well as I burned up the motor....if that happens to this motor I'll be hanging a for sale sign on it and my wife will be hanging me so I better figure this out


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## Lemans guy (Oct 14, 2014)

All good ideas, the book is great but as I he recommends an AFR gauge. I run two wide band 02 sensors one in each exhaust and have Daytona digital dual wide band readout. I can see what the AFR is at idle cruise, from main jets, from secondaries, from accelerator pump and power valve. With that and a vacumn gauge I can tell what carb circuits are pulling.

you don’t need two and you don’t need an expensive one. Holley makes them so does everyone else. Really helps keeping AFR in top condition.

uhttps://m.youtube.com/watch?v=2DYLhJ4hhx0&feature=youtu.be

here is a video about a Holley one. Anyway you are doing all you can and your timing is perfect now.


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## Baaad65 (Aug 29, 2019)

So I asked my friend who has built several cars the latest a 9 second turbo charged '66 Fairlane about the AFR gauge and he said I would drive myself nuts with that gauge on a carburator car so idk how true that is? Ok so inspected the rest of the plugs, #1 and #3 showed those silver specs but the rest good and the timing mark on the strap didn't look to off but I haven't had the plugs out since they went in over a year ago. Set the base at 11° idle is at 21° reset the pcv valve like the directions say and drove it about 10 miles ran about 185° until I drove slower then got up to 195-200° with the puller fan on. Did a couple of wot from a start and it wasn't as good as yesterday with 13° and 36°. Pulled the plugs but need more miles as they looked to clean yet. So my on going problem is still there the dipstick popped up a little bit with oil getting on things, I pulled the breathers and the passenger side had some oil in it and on the foam, drivers just a little spot so I was able to drill out the 8 holes a little bigger from 1/4" to 19/32" and that's it I'm up to the threads. I might call Wagner and see what they say but I can run around the block breathing in those things. Only thing is can think of is my brake booster is teed into the pcv as I don't have a port in the front of this carb but I've read that it can work good either way, I know Wagner discourages that method but I would have to drill another port in the manifold I guess and probably have to pull it. I already put together a special fitting in the manifold port for two small lines, vacuum advance and vacuum gauge but it's to small to add a 3/8" port for brakes, idk what else will keep the pressure down maybe the larger holes maybe a line from a breather to the bottom of the air cleaner? So frustrating.


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## Baaad65 (Aug 29, 2019)

Breathers, top one with enlarged holes.


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## armyadarkness (Dec 7, 2020)

IMO, I still think that your breathers are on the restrictive side. If you look at an oem breather, it's a completely unrestricted mechanism with loose fiber or mesh, on a mild motor. You have a bumped up engine, restrictive holes, and tight foam.

There's no need to keep guessing with this. Take the breathers out, run the wheels off of it, see if the dipstick pops. If so, then your breathers are okay, if not, then you know what to do. You may get a little oil in the engine bay, but you'll fix your car and put this issue to bed.

As for the AFR gauge, to say that it will make you crazy, is like saying that a tape measure will drive a carpenter crazy. Your buddy is implying that they're only for fuel injected cars, but ironically, theyre absolutely usless on a FI car (unless you think that your computer is lying). I think he has it backwards.


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## Baaad65 (Aug 29, 2019)

Well I'll try that test but they sure seem pretty open especially after drilling them the second time and like I said I put in my mouth and can breathe as fast and deep as I can with no problem ( I know a weird test but all I could think of) any suggestions on breathers? Maybe my friend is saying I'll get so many different readings and be adjusting the carb all the time idk, he's had a side business of building cars before I think he's pretty smart and his work looks great but he just made that one comment so I'll have to ask him what he means, he's not much into texting so I'll have to stop by and talk.


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## Baaad65 (Aug 29, 2019)

What's everyone's opinion on the brake booster and pcv teed together, I know Wagner's directions say it interrupts the pcv signal, if it's the only way than I'll have to do some creative plumbing this winter, also I'm not a mathematician but it looks like all the holes in the breather adds up to the same or maybe larger than the hole in the valve cover and I can't make that bigger so then I would need an e vac system.


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## Lemans guy (Oct 14, 2014)

First, that is a very small amount of oil to be worried about, looks totally contained inside the little foam. Remember your crankcase is a swirling tornado of fumes and oil, I don’t think you can expect nothing there.

the dipstick is another matter, it may pop too high or just be too loose on the top. Maybe you need one that fits snug. Call Gene Wagner, the valve can even be set higher with a fixed orifice type set up. So call him and get his take.

You can run without an AFR gauge, you can run actually with no gauges at all. No coolant, no alternator gauge, no oil pressure, no vacumn etc. they are all just there to tell you what is going on. If that drives one crazy none are needed.

Have a shop put a 5 gas analyzer or portable AFR on it to see if it is Lean or rich. Reading plugs is another way, but admittedly less accurate and more subjective and you were concerned of blowing up a lean running motor.

The breathers are open to the crankcase don’t expect absolutely no oil......yours look really small for a few wide open runs.....


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## Lemans guy (Oct 14, 2014)

I use a K& N breather filter on just one valve cover, but it has a filter element all the way around. I think you are making too much of that little bit of oil. It will never be pristine, oil is swirling in there like a cloud.

yes the PCV hose should be alone, that would be ideal. But maybe you should drive it some more and see. And talk to Wagner. This dipstick's should be snug as well.

yes you see the feel with 34 degrees is different, but since you are concerned about detonation now, run it that way awhile and check the plugs listen for pinging and get the feel for it. Then if it all looks good, dial the base up 2 degrees for 13 and 36 and run there and recheck plugs and listen etc.


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## armyadarkness (Dec 7, 2020)

I work with foam a lot (long story). There is open cell foam, and closed cell foam. Your foam looks like a tighter, restrictive foam... regardless.

Just like with a carb and exhaust, We're talking about volume and displacement here, so there's no need to "ball park" it. Yes, you can say that your breathers look pretty open, but do they look 6.6 liters at 5500 rpm open? I'm inclined to think no. 

Your engine is sealed and you have eight pistons each trying to displace all of that air, 5000 times a minute, through sixteen, 1/4 inch holes, which are also blocked by foam.

However, as I mentioned earlier, one balls-to-the-wall run with no breathers will tell you whether or not theyre big enough


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## armyadarkness (Dec 7, 2020)

Baad... My first run after installing the Wagner, I roasted the tires, went sideways, broke loose again in second, got home and had no breathers at al! And they were wide open foam! Ive since made 3 different sets, and am still searching for perfect ones.


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## Lemans guy (Oct 14, 2014)

And you might try taping off the bottom of one breather and retrying, pulling a Vacumn needs some restriction, maybe two is too much. Try that and see if it is any better…


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## armyadarkness (Dec 7, 2020)

lol. Now I'm confused, too!


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## Baaad65 (Aug 29, 2019)

Lemans guy said:


> I use a K& N breather filter on just one valve cover, but it has a filter element all the way around. I think you are making too much of that little bit of oil. It will never be pristine, oil is swirling in there like a cloud.
> 
> yes the PCV hose should be alone, that would be ideal. But maybe you should drive it some more and see. And talk to Wagner. This dipstick's should be snug as well.
> 
> yes you see the feel with 34 degrees is different, but since you are concerned about detonation now, run it that way awhile and check the plugs listen for pinging and get the feel for it. Then if it all looks good, dial the base up 2 degrees for 13 and 36 and run there and recheck plugs and listen etc.


The dipstick seems pretty snug so to pop it up is a little concerning, never had oil in the breathers but I have them opened up so much guess that will happen, I'll just clean them out periodically. Ya I have to put some more miles on it and check the plugs that should tell me what direction to go with up jetting.


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## armyadarkness (Dec 7, 2020)

Oil in the breathers is absolutely normal. You're blowing air out through them and there's oil sitting where the air is coming from.


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## Baaad65 (Aug 29, 2019)

Me too, everyone said mine were way too restricted and now I should tape one off for a vacuum?


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## Baaad65 (Aug 29, 2019)

Also I did have to remove the valve cover baffles as they interfered with the rockers so that will contribute to the oil in the breathers I would guess.


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## Baaad65 (Aug 29, 2019)

So tomorrow I'll try and call Wagner and that tuning site 👍


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## Baaad65 (Aug 29, 2019)

Thanks again for everyone's help and suggestions I know you're probably exhausted about this subject I know I am, but it's great to have a place for good information besides every goofball on the internet..glad I joined and we'll get it figured out 👍


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## armyadarkness (Dec 7, 2020)

Baaad65 said:


> Me too, everyone said mine were way too restricted and now I should tape one off for a vacuum?


Im sure he'll clarify it for us, soon.


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## armyadarkness (Dec 7, 2020)

Baaad65 said:


> Also I did have to remove the valve cover baffles as they interfered with the rockers so that will contribute to the oil in the breathers I would guess.


ABSOLUTELY! They make baffles for a reason, and Gene at Wagner will enforce that. However, it's *much more* important to have the baffles in place when the PCV valve is in the covers, and the baffles in that case are reducing the engine oil, which is being sucked into the intake.

In our case, the baffles would merely reduce oil which would blow out, but it's all minute and not detrimental to performance.


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## armyadarkness (Dec 7, 2020)

Or... It's important to have the baffles on the intake side, not so important to have them on the exhaust.


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## armyadarkness (Dec 7, 2020)

BTW... Gene is going to tell you to run without the baffles, in order to narrow it down. So, even though he's a genius and I'm one of the internet goof balls you were worried about, the advice will be the same.


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## PontiacJim (Dec 29, 2012)

You may want to read this on spark plugs as there is some good info that may relate. 









Spark Plugs


Just wondering what spark plugs people are using on a 389 TriPower Also is there an electronic upgrade for the distributor or should I keep running the old points and condenser Thanks Jedi




www.gtoforum.com


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## Baaad65 (Aug 29, 2019)

armyadarkness said:


> BTW... Gene is going to tell you to run without the baffles, in order to narrow it down. So, even though he's a genius and I'm one of the internet goof balls you were worried about, the advice will be the same.


You're not a goofball at all and I don't have room for baffles unless they're a 1/4" because of the rockers.


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## Lemans guy (Oct 14, 2014)

The reason I mentioned testing with tape is you seemed to have trouble getting it dialed in.

so look at it this way, to pull a vacumn in a closed box let’s say the box has to be mostly closed, if one side of the box was opened or even half opened you could not pull a vacumn.

so now let’s say you had a closed box and drilled 3 large holes with a hole saw, still hard to pull a vacumn, now let’s say you have two breathers and you are trying to pull a vacumn, better, but somewhere there 2 big breathers, one big breather, 1 1/2 big breather it will pull a stronger space in the space (crankcase) that you are trying to evacuate.

yes you have pressure that you are trying to defeat,so the PCV is evacuating that and just past that for a 1 to 3 HG in the crankcase.

The breathers are to let fresh air in,.....but there is a right place. I am not saying that you should run one breather, just testing with tape to see the result. It may be worse....

I use one big K&N breather and it does great, but two might open it too much.

Hope that helps, and I am right below Army on the internat gauge, “Hot-Rod HacK”!

Gene Wagner should be able to guide you as well


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## Lemans guy (Oct 14, 2014)

I saw PJ ‘s mention in the other thread, he is correct you do not need baffles under the breathers. Just under the PCV so it does not pull too much oil.


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## armyadarkness (Dec 7, 2020)

Baaad65 said:


> You're not a goofball at all and I don't have room for baffles unless they're a 1/4" because of the rockers.


You don't need baffles in your VCs for the breathers. IF anywhere, you'd need one in the valley pan for the PCV. You're setup is fine, we just need to dial it in.


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## Lemans guy (Oct 14, 2014)

Exactly, think this if you removed one valve cover, that PCV would never be able to pull a vacumn on the crankcase.....there is a sweet spot on air in and vacumn out...you will get it.


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## Baaad65 (Aug 29, 2019)

Ok so when I posted pictures of my breathers before the mods everyone said they were way restrictive so I drilled them and still had the problem so I've drilled them a little more but haven't driven it yet. So I understand pulling a vacuum needs some restriction but all the oil fumes have to be pulled through the 3/8" pcv hose so is that big enough on this big hp motor? and if so than the pcv valve better not restrict that flow that's what I have to get right and still might be the problem, and then if it's not evacuating enough fumes and pressure builds up why is it blowing out the dipstick and not getting relieved through two breathers that are really opened up in my opinion, path of least resistance, maybe I'm getting close as the dipstick isn't popping up as much and now I'm getting some oil in the breathers especially the passenger side which I don't understand that as they are both located to the rear.


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## armyadarkness (Dec 7, 2020)

I think that you're going to be fine. I also think that a lot of your confusion is due to the fact that you're trying to infinitely solve your issue on the internet, but you should be trying to solve it under the hood of your car.

It's great to come here and get direction, advice, and specifications, but if you try and substitute this for practical, hands on experience, then you're never going to get anywhere... or at best, you'll be completely reliant upon the web for the longevity of your car.

Based on what I see of your car and have read, you're a mechanic and you have aptitude. Now you also have advice. IMO, you need to start blending the two.

Drive the car. If the dipstick pops again, then make another pass with no breathers. Then come back with the results. There's a 50% chance that your problems will be solved by then, and if not, then youll get new advice, based on the process of elimination.

The PCV is a very basic system with simple cause and effect operation. I really feel that if you persist here, without testing on the car, that you're going to just confuse the crap out of yourself. And if youre going to get confused, let it be on something like a transmission rebuild!


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## Lemans guy (Oct 14, 2014)

First I think it is unrealistic to expect that absolutely no oil will get into the unbaffled breathers.

it is a very small amount from your photos, it did not leave the foam. I get some oil in My K&N, but nothing compared to it without the Wagner. In addition are you getting oil dripping from any seals and gaskets? Rear main? Valve covers? Distributor gasket? I used to get it at all 3, now nothing.

The dipstick issue may settle with a little more tweaking in, at any rate you are close.

I noticed that you could tell the performance difference from 34 to 36 So monitor it you may be able to go back to 36.


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## armyadarkness (Dec 7, 2020)

When I started putting my car together back in December, I was just like you. I had 12 irons in the fire at once and I was frantically trying to fix it all. Carbs, timing, valves, heads, wires, relays, lights... It makes sense to do them all at once. Waiting on the carb? Work on the suspension. Waiting on a bumper, do the brakes... But one day, a had an issue and I thought the motor was blown. I called all of the mechanics that I knew and I spent all night researching it on the web. Fortunately, the local mechanics didnt answer the phone, because if they did, Im sure that they wouldve had me tow the car to be repaired.

In the absence of experts, I went over the car myself. Within 20 minutes, I found that a new, $12 part was defective. It took 5 minutes to replace it. It was a very inconvenient and costly lesson. I shouldve had faith in my own ability.


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## Baaad65 (Aug 29, 2019)

Ok talked to Gene for 45 minutes and what a nice guy and patient which is hard when talking to me, here's his suggestions I'm going to try....drill some more holes in the breathers, the center hole at 3/4" is good by his calculations, try to put some kind of baffles back leaving 3/8" clearance from the breather end to avoid oil in the breathers, set the valve to the fixed orifice configuration which won't hurt anything just have to keep an eye on the plugs but he doesn't think I'll have any problems, make sure I'm not over filling with oil so I need to check the capacity of the pan, is it 5.5 in the pan and .5 in the filter for 6? the description on Butlers build sheet just says stock baffled pan 6 quarts, so is that 6 plus the filter? I always put in 6, he said I could even run a little low on oil which might help. And by the way he doesn't like Wix filters to restrictive, don't know if that's true and the high volume pumps can cause problems he said, high pressure is ok but those are arguments for another day and thread. Lastly and I knew this was coming he absolutely doesn't want the pcv teed in with the brake booster, says when I'm on the brakes the pcv isn't functioning and I could be building crank case pressure then I let off and hammer it and that can be part of the problem too so I have to do some creative plumbing because no 3/8" port up front on the carb but I do have a 1/2" carb spacer I can tap for a fitting. Also he thinks ported vacuum for the vacuum advance is better but again another argument I'm not worried about.


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## armyadarkness (Dec 7, 2020)

Dont you have manifold ports for vacuum? Run the booster off the carb and the PCV off the manifold port.


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## Baaad65 (Aug 29, 2019)

I do but I put the vacuum advance and vacuum gauge to this port so I would have to run one or both lines up to the front of the carb that's why I thought maybe just drill and tap the spacer but he would like to see both 3/8" lines balanced one in front and one in back it will still work both being in back.


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## Baaad65 (Aug 29, 2019)

Lemans guy said:


> First I think it is unrealistic to expect that absolutely no oil will get into the unbaffled breathers.
> 
> it is a very small amount from your photos, it did not leave the foam. I get some oil in My K&N, but nothing compared to it without the Wagner. In addition are you getting oil dripping from any seals and gaskets? Rear main? Valve covers? Distributor gasket? I used to get it at all 3, now nothing.
> 
> ...


No oil leaks, and after this latest test drive just about the same or little less oil in the passenger breather none in the driver's. Gene brought up a good point since the only time blow out the dipstick is under full throttle which renders the pcv useless so there won't be any vacuum therefore I need better breathing to relieve the crankcase pressure which I think I accomplished just today. It did have a slight hesitation when I mashed the pedal to go that I don't remember at 36° advance but I'm afraid I'm running lean so I'll leave it there until I get some more miles on the plugs for a good read, if it's still looking lean do you up jet just the secondarys or both primary's too...I'm running 74 up front and 82 in back on a Quickfuel 850 dp QFT 31 squirters and pink pump cams....guess it's a try it and drive it thing.


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## PontiacJim (Dec 29, 2012)

Stock capacity oil pan IS 5 quarts in the pan as I stated. 1 qt or whatever based on the size of the filter used. UNLESS Butler is selling extended pans with higher capacity, 5 qts or if it is an aftermarket pan said to hold more oil, the pan holds 5 qts. Over filling the pan can cause some problems.

If oil were to be low at 5 qts, watch your oil pressure gauge when you nail the gas. If it fluctuates in the least amount, then extra oil is what is needed.

Now this has been covered I believe on this forum (?, I know over at PY it was covered), that the 1967 engines said to fill to 6 qts in the pan, plus 1 qt for the filter for a total of 7 quarts (6.5 with short filter). The engine also was either manufactured with the 5 qt dipstick and later changed to the 6 qt dipstick and/or replaced when the car came in for service. Reason being? Too many GTO owners were racing the cars and letting the oil level drop down and engines were coming in for warranty because of oil failure. So Pontiac sent out a service bulletin on replacing the 5 qt dipstick with the 6 qt dipstick and overfill the pan 1 qt. So that is where the confusion comes from and when I emailed Butler, they did not know of a 6 qt factory pan.

"Pontiac Service News Flash number 64-16 (10-18-63) and 65-53 (12-22-64) verified that the oil capacity on all Pontiac V-8 should be five quarts - six quarts with filter change. Some 1964 models were manufactured with a four quart dipstick; the five-quart dipstick , part number 9776085 (code MF), should be installed.

Pontiac Service News Flash number 66-5, dated 10-15-65, reported that the 1966 owner´s guide and shop manuals were incorrect regarding oil capacity. The correct capacity was six quarts - seven with oil filter change."

"Note the dipstick from a 67 says to add 6 quarts and the 71ish dipstick says to add 5 quarts. HOWEVER, they both have the same add point, it's the full point which is different. My 6 qt sticks came from original 67 engines and they are identical. The 5 qt sticks with the holes came from 71-74 motors I've had. Even if the lower tubes put the dipstick at a different angle between the years with the different windage trays, then both the ADD and FULL marks should be different, not just one. "

"Dealers got tired of people complaining the oil light was coming on at stopsigns. usually because of being 2-3 quarts low. the factory just put another quart in (overfill) for the idiots."

"I'm going to answer your question based on my own experience working on the grease rack at a Pontiac dealer in 1970, and then continued my employment as a service tech for 45 plus years. 
The pans fundamentally are the same, from 1955-1981, the small differences are baffles in the later pans. The differences in capacity are due to the markings on the dipstick, or gauge, as GM calls it. 
Capacity for the early engines is 5 in the pan, 1 in the filter, which used the long canister with a cartridge 55-59. In 1960 they switched to the long spin on filter 5, and 1. 1967 only, 6 in pan, 1 in the filter. In 68 they returned to 5, and 1. Pontiac used the same basic pan, *just changed the markings on the dipstick. *For some reason the engineers changed the gauge (dipstick) markings for 67. I have compared the 2 sticks side by side, and the markings are different. GM had just jumped from 12/12,000 warranty, to 5/50, so I can't help but to connect it to that.
The new 5 year-50,000 mile warranty that all the manufacturers were all coming out with at that time. I've never heard the reasoning why the change for one year, and then reversal back to 5 in the pan, and 1 in the filter in 68."


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## Baaad65 (Aug 29, 2019)

Great information, I switched out the dipstick for a chrome one that said for Pontiac, put 6 quarts in and it's right on the full line. It's a '72 block and here's a picture of the build sheet the pan description is in the center but the part number for cut off, kind of confusing as it says 6 quart pan so does that mean 6 in the pan + filter and does a filter hold a whole quart it seems like a little less to me idk ?


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## PontiacJim (Dec 29, 2012)

Baaad65 said:


> Great information, I switched out the dipstick for a chrome one that said for Pontiac, put 6 quarts in and it's right on the full line. It's a '72 block and here's a picture of the build sheet the pan description is in the center but the part number for cut off, kind of confusing as it says 6 quart pan so does that mean 6 in the pan + filter and does a filter hold a whole quart it seems like a little less to me idk ?
> View attachment 143504


Stock pan - 5 qts, filter 1qt + or - depending on size. However, I see 80 PSI oil pump which I am not a fan of unless you have large oil clearances, ie race clearanced mains & rods, or plan on spinning higher RPM's. So it might be good to have the extra qt once that pump gets to pumping as it is most likely their Pro 80 PSI pump which pumps more volume along with the higher pressure. I have the 60 PSI Pro pump and it flows more volume. Funny thing is that Butler is not consistent in what they tell people. I inquired about the 80 PSI pump for my 455 - which has the larger main journals - and they said that I did not need it and to use the 60 PSI Mellings pump. So here we see an application for the 80 PSI pump and you have the smaller 3" mains. I can only assume they factored in some higher RPM's coming out of your engine. I don't figure I'll get 5,600 RPM's out of mine, so 60 PSI will be plenty.

All you can do is go with what Butler says about the build seeing they built the engine and know how to build a Pontiac. It is hard to comment or critique another's build when it is already assembled - especially a well known and reputable Pontiac engine builder.


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## Lemans guy (Oct 14, 2014)

Definitely would up the secondaries to 84, I would up that squirter as well, a 31 is pretty small for that engine.my quick fuel had a small squirter from the factory as well, running a 40 to get me the best AFR, that is why the gauge helps.

also on your vacumn leads, I run a vacumn manifold,JEGS summit has em, about 40 bucks, you canrun a gauge, blend doors, even a trans vac off it.

there are also stacked vacumn manifolds to give you more access. I would run the brakes direct to a 3/8 port and the Wagner PCV to the big port off the carb, the dist advance Can be run direct as well and you can also feed a vac manifold mounted on the firewall fir gauges, etc.

Some guys like ported vac but I set up all of em with full manifold vac for smooth idle and idle cooling it cannot be beat, why give that up? To run a hotter idle with ported heating up your exhaust , engine and fuel?

Once the throttle starts to transition they are the same, I think many guys just set em up with way too much advance, not 10 degrees get problems and start complaining, but hey you had too much to begin with........


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## Baaad65 (Aug 29, 2019)

Right, I'm playing the hand I was dealt.


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## Baaad65 (Aug 29, 2019)

Lemans guy said:


> Definitely would up the secondaries to 84, I would up that squirter as well, a 31 is pretty small for that engine.my quick fuel had a small squirter from the factory as well, running a 40 to get me the best AFR, that is why the gauge helps.
> 
> also on your vacumn leads, I run a vacumn manifold,JEGS summit has em, about 40 bucks, you canrun a gauge, blend doors, even a trans vac off it.
> 
> ...


I have seen those manifolds I'll check them out, ok I told the guy who builds carbs all my motor specs and that's what he came up with, only thing I changed was to the 1.65 rockers but it's a trial and error thing I guess, so you think leave the primaries alone? I'm going to try the timing up again because the hesitation wasn't there with 36 but still need to see those plugs.


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## Lemans guy (Oct 14, 2014)

I would leave it at 74 for the moment, and you have 2 squirter son that DP so the 31 should be plenty,....what power valves and Power valve channel restrictions (PVCR) you run has a lot to do with AFR when throttle is down.

a higher rated power valve and larger PVCR will make running richer as vac drops.

So for example while tuning and watching my vac gauge, I could tell I wanted more power (richer) whenever pulling a long highway hill. This often happens without secondaries on.

My vac was about 8hg from vac gauge and AFR was still on idle circuit, which you ride on for up to 2 or 2500 RPM’s. So I changed the power valve to an 8.5 instead of the factory installed 6.5.

Now I was getting a rich mixture pulling those Hills. But it was too rich, down to 10’s....that was factory rich PVCR which would have come on at 6.5 HG but I needed it sooner.

So since it was a Quick fuel carb I could put in leaner PVCR to get the power valve to 12.2 AFR. When it comes on....perfect for power, remember this is without secondaries on.

somthere is a lot of curving your carb you can do with your quick fuel and a vac gauge and AFR meter in the cab.

you are improving it each day, stay with it!


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## Baaad65 (Aug 29, 2019)

Got it, ya I'll wait for some more miles on it and check the plugs if they're still real white I'll richen things up so I can get my 36°and maybe send some pictures to that site PJ recommended...here's the build sheet on it.


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## Lemans guy (Oct 14, 2014)

You got a great carb set up there, set up nice to start with and easily tunable. Parts and jets are easy to get from Quick Fuel. I love mine.


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## Lemans guy (Oct 14, 2014)

Who is this carb builder?


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## Baaad65 (Aug 29, 2019)

Thanks, I have some 84 +86 jets for the rear and a pair of 75's for the front but those are only one drill size up, the guy said to stay with the 6.5 power valve because I have higher manifold vacuum.


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## Baaad65 (Aug 29, 2019)

Lemans guy said:


> Who is this carb builder?


A guy I found on Ebay.


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## PontiacJim (Dec 29, 2012)

Baaad65 said:


> Thanks, I have some 84 +86 jets for the rear and a pair of 75's for the front but those are only one drill size up, the guy said to stay with the 6.5 power valve because I have higher manifold vacuum.


"We can start with some basic tuning recommendations. For a street car with an automatic transmission, use your vacuum gauge to read the idle vacuum of a fully warm engine at idle in gear. Let’s put this idle vacuum at 13 “Hg. *If we divide the idle vacuum in half*, this results in a 6.5 “Hg power as a great starting place for tuning.

This will open the power valve when the manifold vacuum reaches 6.5 “Hg or lower.* Some tuners prefer to open the power valve a little earlier to prevent the engine from running lean at heavier part-throttle that could cause detonation problems. In this case, the tuner might raise the power valve closer to 8.5 or perhaps 9.0 “Hg.*

You can find plenty of discussion regarding a power valve that will or will not open at idle. The idea behind having a power valve that is open at idle is that the the idle and power enrichment circuits are separate and therefore, there will be no effect. While the idle and main circuits are separate, an over-rich main circuit at idle will have an effect on idle quality. The power valve needs to remain closed at idle."

Taken from this article:









How To Tune The Power Valve In A Holley Carburetor


How to ensure your Holley carburetor is using the right power valve for your engine. Holley carburetors have a power enrichment system that provides fuel to the main power circuit during heavy loads or under full throttle situations. The vacuum operated power enrichment system is controlled by a...




www.holley.com


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## Baaad65 (Aug 29, 2019)

Great information, I'll check out the article, so if I'm running 15-17 inches would it be beneficial to tune it down to 13 ? Always thought tune it to the highest vacuum reading, and I have four corner idle adjustment so which ones do you use to dial down front or rears if that's what I need to do? Also it's a manual transmission.


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## Lemans guy (Oct 14, 2014)

Exactly you do not want the power valve open at idle, but on demand when you need power.

it opens as the vac drops....it will open at it’s rating. It does not control the amount or flow of fuel, and it is not fuel and air like the idle circuit but fuel like the main jet and it feeds it not through the idle circuit but through the ventire.

The power valve channel restrictions (PVCR) which are like mini jets on the quick fuel are under the power valve, when it opens the fuel flows through those restrictions.

PJ is right about they all start at about half idle vacumn reading, 6.5 is what quick fuel and Holley put in there. But you have to drive and see if that is good for your set-up. With that double pumper you could even prefer a 4.5.... you just have to see. Watching your vac gauge will help.


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## Lemans guy (Oct 14, 2014)

Venturi......


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## Baaad65 (Aug 29, 2019)

Ok idk if there was an answer in there I missed, so I should try tuning the vacuum down to 13.5 as a jumping off point and which screws the fronts since the power valve for the secondarys is blocked off?


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## PontiacJim (Dec 29, 2012)

Baaad65 said:


> Ok idk if there was an answer in there I missed, so I should try tuning the vacuum down to 13.5 as a jumping off point and which screws the fronts since the power valve for the secondarys is blocked off?


How do you tune vacuum down?


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## Baaad65 (Aug 29, 2019)

Turn the screw in or out and the vacuum goes down but it doesn't run as good, that's what I was asking is that really a good method?


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## 67ventwindow (Mar 3, 2020)

Baaad65 said:


> Lastly and I knew this was coming he absolutely doesn't want the pcv teed in with the brake booster, says when I'm on the brakes the pcv isn't functioning and I could be building crank case pressure then I let off and hammer it and that can be part of the problem too so I have to do some creative plumbing because no 3/8" port up front on the carb but I do have a 1/2" carb spacer I can tap for a fitting. Also he thinks ported vacuum for the vacuum advance is better but again another argument I'm not worried about.


 The 289 in my cougar has the pvc connected to the factory spacer block.I had the same issue when I installed an aluminum intake.so I went back to a spacer with the port. I run a vacuum tree with my gauge, damper doors and head light doors. I try not to put two high use vacuum draws on one tree.


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## PontiacJim (Dec 29, 2012)

Baaad65 said:


> Turn the screw in or out and the vacuum goes down but it doesn't run as good, that's what I was asking is that really a good method?


Are you talking about the idle mixture screws? Don't mess with anything on the carb at this point. You had a picture of the vacuum gauge face showing near 20" Hg, has that changed? Half of 20 is 10", so according to the article I sighted, you might want to go with the 8.5 power valve? Keep in mind I don't know Holley carbs, period. So I am only basing my opinion on what I take from the article.

Initial timing needs to be as pointed out, closer to 21-23 degrees with the vacuum canister connected, or 11-13 with the vacuum plugged because you will get 10 additional degrees of advance as soon as you reconnect it.

Make your Total at 34 degrees @ 3,000 RPM's. That should get your timing in order.

Then tinker with the carb and get it dialed in. As pointed out, an Air/Fuel gauge can be useful, but you can also do it without it. Just read the plugs after each change. Don't make more than 1 change at a time.

Here is what Butler sells for the 1972 and up heads - taper seats. The 5 series is hotter according to their NGK info. The 6 is one step cooler.



https://butlerperformance.com/c-1291214-ignition-electrical-spark-plugs-plugs-for72-and-later-cast-iron-heads.html


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## Baaad65 (Aug 29, 2019)

I have the timing set like that, I'm get about 15-17 inches of vacuum, those pictures of the plugs looked lean but now I have the timing dialed in so I cleaned off the plugs and need some more miles on them to see how they look and will determine what to do...thanks for the spark plug info I'll look into them👍


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## coyote595 (Dec 4, 2019)

On NGK plugs, the lower the number, the hotter the plug. A 5 is one step hotter than a 6. NGK are the brand of plug I have had the best luck with, starting with my very first dirt bike at age 11.


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## PontiacJim (Dec 29, 2012)

coyote595 said:


> On NGK plugs, the lower the number, the hotter the plug. A 5 is one step hotter than a 6. NGK are the brand of plug I have had the best luck with, starting with my very first dirt bike at age 11.


My bad in mis-reading the Butler info. I just edited it so it is now correct. Lower number is hotter.


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## Baaad65 (Aug 29, 2019)

I don't remember posting a picture of the gauge being used and I get 15-17 inches on the factory gauge in the car that's hooked to the manifold and my portable hooked to the carb so is the 6.5 valve still ok because that's what the carb builder said should be good with that vacuum. The iridium plugs I have were a step colder from the original ones Butler used when I got the motor so I'm going to stick with those for now, they weren't cheap.


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## armyadarkness (Dec 7, 2020)

My base was at 14 and with the can, I was 24 or so. No knocking and the car cruised like a dream, but I finally decided to set it to the prescribed method here. 12 base, 10 from the can, and 36 total, which required swapping out the 21 bushing for a 25.

There's no improvement anywhere, in fact, it seems like it wants to die now after I start it, but I'm going to lean out the carb a bit and continue evaluating.


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## Baaad65 (Aug 29, 2019)

I like the performance of this carb only thing is I don't have a choke so I have to sit in the car and keep the rpms up for a couple of minutes before it will idle on it's own which I'm not sure why if everything is set up correct what does a little warming of the engine do that it won't idle right away, the carb puts the same gas in the motor hot or cold, the spark is the same so what is it?


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## 67ventwindow (Mar 3, 2020)

The one thing a choke does for you is reduce air giving you a rich condition. So you are pumping the pedal gives you that condition. Fuel atomizes better in a warm engines instead of pooling as it does on a cold engine. So you need more fuel to get a good mix in the chamber when cold.


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## Baaad65 (Aug 29, 2019)

Ah yes forgot about the pooling fuel, makes sense...thanks


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## Lemans guy (Oct 14, 2014)

6.5 power valve is Ok, use it and see how it does.

67 vent is right of course, a cold intake and engine does not facilitate the vaporization of the fuel. Liquid drops to the bottom of the intake when cold. As it warms the fuel vaporizes and enters through the valves ...

Right army once timing is right just reset your mixture, so the carb is right.


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## Lemans guy (Oct 14, 2014)

Army you can run a 21 bushing, now that you have a 10 degree vac can you have room to dial up the idle timing...remmeber you had much more in that vac can before.

A 21 bushing means 21 Centrifigal advance, then set you base at 15 for 36 total

your idle timing will then be 15 + 10 Vacumn = 25 @ idle. These are good settings

So now you have 12 base + 10 vac = 22......if you like 25 better do it. Those are all great numbers and each car has to feel right. With no pinging and strong response.


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## PontiacJim (Dec 29, 2012)

Baaad65 said:


> I don't remember posting a picture of the gauge being used and I get 15-17 inches on the factory gauge in the car that's hooked to the manifold and my portable hooked to the carb so is the 6.5 valve still ok because that's what the carb builder said should be good with that vacuum. The iridium plugs I have were a step colder from the original ones Butler used when I got the motor so I'm going to stick with those for now, they weren't cheap.



This is not you from post #32? Maybe I misunderstood how it reads being it is old? It shows almost 20" Hg on the green needle and thought that was correct or is it not evn hooked up and it is the read needle, so that was where I got it from. My bad if I misread the face.


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## Baaad65 (Aug 29, 2019)

Yes that's on my toolbox, maybe I should look into a little bit newer one ha ha, but my vacuum gauge in the car reads about 16inches at idle so hopefully that's accurate, don't know if it can calibrate it.


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## Baaad65 (Aug 29, 2019)

....it appears not to be on zero don't know if that matters?


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## Lemans guy (Oct 14, 2014)

Usually there is a calibrating screw, either on the back or front of the gauge, be gentle and don’t turn it too far, a small bit may bring it to zero. But even at that if it reads 16hg and it’s up 2 you have 18 Hg.


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## Baaad65 (Aug 29, 2019)

I'll have to check into it, in 4 1/2 years I never noticed it not being on zero until I took that picture...but the hastings gauge reads 15-16.


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## Baaad65 (Aug 29, 2019)

Found an allen head screw on the back but it just tightens or loosens, nothing on the front I'll have to research it some more.


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## Lemans guy (Oct 14, 2014)

Yeah, it is reading 1 Hg actually...I might leave it be rather than breaking it...

looks like a .nice original gauge.


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## armyadarkness (Dec 7, 2020)

Lemans guy said:


> Army you can run a 21 bushing, now that you have a 10 degree vac can you have room to dial up the idle timing...remmeber you had much more in that vac can before.
> 
> A 21 bushing means 21 Centrifigal advance, then set you base at 15 for 36 total
> 
> ...


The car just feels sluggish. Off the line it's an instant tire roaster and light throttle cruise feels and responds awesome, but heavy pedal business just lumbers on like a sick elephant. WOT is deadly from 70mph and on, but around-town bashing is very lackluster to me. I never have pinging, even when it was the other way, I was just hoping for better response, but it was definitely idling better with the 21 bushing than the 25. 

Now when I start it, it seems like it wants to die, and it sometimes does, unless I goose the gas. Yes, I did reset the mixtures after the timing.


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## Lemans guy (Oct 14, 2014)

Hotter cams like the higher idle timing,....so use the 21 bushing. Probably just need a little more pedal to drop the vac can out....it is dropping out as throttle is opening and timing increasing from RPM’s going up.....but you need to get that vac way down.....as well


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## Lemans guy (Oct 14, 2014)

Could also be carb circuits, if AFR is not right at certain power demands...


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## armyadarkness (Dec 7, 2020)

Vac can is a solid 10 now, so at this point, I do think I'll change over to carb tuning. Gonna jet down and o for crisp


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## Lemans guy (Oct 14, 2014)

yeah I do think that may help you are very close on it all.........


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## michaelfind (Dec 14, 2018)

Baaad65 said:


> ....it appears not to be on zero don't know if that matters?


I had to open mine up to calibrate it, but it was not complicated once you remove the back cover. Do be gentle. Obviously, these are old "fine tuned instruments."

Now what was complicated was changing the vacuum advance can and installing the vacuum advance corrector in my Pertronix distributor. I think the MSD solution looks much simpler. With the Pertronix, you essentially have to disassemble the whole thing, and it is much more complicated than a stock distributor. But anyhow, I got that done and my numbers are better now (I think). However, I was idling cooler before, 160-180 degrees, when I still had 16 degrees of vacuum advance. However, we were not yet into summer so ambient temperatures were better.

I tried the recommended 13 base, with 10 vac, and 20 centrifugal. With my Pertronix, I don't have the option for a 22 degrees of centrifugal. It did not idle as well and the temp was about 200-210, even with vacuum advance connected. 

Since I have the 16 degrees of vacuum advance corrected down to 10, I went back to 16 degrees base. Now I have timing of 36 all in at 3000 rpm without vacuum advance connected. With vacuum advance connected, idle is at 26, with 46 at 3000 rpm. My idle temp went back down to 180-190. No pinging as of yet. I'm no longer at risk of getting into the 50 degree range coming off WOT, so I should be safer now, right?


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## armyadarkness (Dec 7, 2020)

michaelfind said:


> I had to open mine up to calibrate it, but it was not complicated once you remove the back cover. Do be gentle. Obviously, these are old "fine tuned instruments."
> 
> Now what was complicated was changing the vacuum advance can and installing the vacuum advance corrector in my Pertronix distributor. I think the MSD solution looks much simpler. With the Pertronix, you essentially have to disassemble the whole thing, and it is much more complicated than a stock distributor. But anyhow, I got that done and my numbers are better now (I think). However, I was idling cooler before, 160-180 degrees, when I still had 16 degrees of vacuum advance. However, we were not yet into summer so ambient temperatures were better.
> 
> ...


EXCELLENT! Yeah the correctors on the old style dizzy's SUCK to install.


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## Baaad65 (Aug 29, 2019)

michaelfind said:


> I had to open mine up to calibrate it, but it was not complicated once you remove the back cover. Do be gentle. Obviously, these are old "fine tuned instruments."
> 
> Now what was complicated was changing the vacuum advance can and installing the vacuum advance corrector in my Pertronix distributor. I think the MSD solution looks much simpler. With the Pertronix, you essentially have to disassemble the whole thing, and it is much more complicated than a stock distributor. But anyhow, I got that done and my numbers are better now (I think). However, I was idling cooler before, 160-180 degrees, when I still had 16 degrees of vacuum advance. However, we were not yet into summer so ambient temperatures were better.
> 
> ...


Ya think I'll leave it alone and buy a new gauge for checking under the hood, it does look cool though  I got lucky with the MSD limiter because that did sound like a pain.


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## Lemans guy (Oct 14, 2014)

Michael your numbers are spot on.......I set em all @ @ 36 total, and with that 10 degree vac can you can dial up the base to 16 like you said for a 26 degree idle....

all in by 3000 great as well. I would leave the timing there and work with other stuff.

when you have those 16 and 20 degree vac cans it gets the idle way too high.

and yes 36 total plus 10 for 46 at a light throttle cruise is your max...perfect on today’s gas.

Army said he liked his idle better at 25...real hot cams like 260 lift....Use the upper end 28, 30 degrees at idle with 10 vac in that number....

mid range cam...mid range number, like 240 lift....24 to 28 at idle (with ten from vac)

mild cam 220 lift......20 to 24 at idle (with ten from vac)

each engine is unique and these are ranges guides not hard and fast, but place to shoot for to get your timing cool and smooth.

Like Michael said some distributors and not quite as easy to calibrate, MSD has made it much easier, so you have to work with them to get it right.

Just realize that most cars you see are driving with messed up timing curves, and you guys are curved it. This is fine tuning here!

Drive em and enjoy it


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## PontiacJim (Dec 29, 2012)

Lemans guy said:


> Michael your numbers are spot on.......I set em all @ @ 36 total, and with that 10 degree vac can you can dial up the base to 16 like you said for a 26 degree idle....
> 
> all in by 3000 great as well. I would leave the timing there and work with other stuff.
> 
> ...



Keep in mind that in post #218 were the photos of the spark plug that looked like it had aluminum flecks on it. Thought the suggestion was to back down a bit on the timing? along with a carb adjustment.

Detonation is not always audible.









Timing


Balancer is at zero....when light is reading the advance




www.gtoforum.com


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## Lemans guy (Oct 14, 2014)

Yes I do agree here, as have said many times. I set them at 36 and check for pinging, detonation evidence of that, back down base two degrees and retest.

Still evidence back down 2 more degrees to 32 And retest, listen check plugs etc. PJ is right that was already discussed, sorry that I did not reference that.


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## michaelfind (Dec 14, 2018)

Lemans guy said:


> Yes I do agree here, as have said many times. I set them at 36 and check for pinging, detonation evidence of that, back down base two degrees and retest.
> 
> Still evidence back down 2 more degrees to 32 And retest, listen check plugs etc. PJ is right that was already discussed, sorry that I did not reference that.





PontiacJim said:


> Keep in mind that in post #218 were the photos of the spark plug that looked like it had aluminum flecks on it. Thought the suggestion was to back down a bit on the timing? along with a carb adjustment.
> 
> Detonation is not always audible.
> 
> ...


And the confusion is my fault for throwing in some of my own numbers on this thread that I did not start. I think the plugs were from Baaaad. I have not posted any plug pictures. I'm sorry about adding to the confusion. This huge thread has been helpful for many of us who have chimed in here and there. Thanks to all you experts, especially PJ and LeMans Guy!


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## armyadarkness (Dec 7, 2020)

You didn't add to any confusion. Everyone here is either trying to teach, trying to learn, or both. Sometimes you hear something over and over again, and it makes no sense, and then one day, poof! These discussions are healthy and an essential part of the bigger picture.


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## Lemans guy (Oct 14, 2014)

Exactly! We all Just want everyone get Perfect timing and fun running…!


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## Lemans guy (Oct 14, 2014)

Just curved a 1967 corvette distributor this morning, 327 350 HP…..turned out real good….

One of the best things to do for your engine is to get that timing dialed in.


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## PontiacJim (Dec 29, 2012)

michaelfind said:


> And the confusion is my fault for throwing in some of my own numbers on this thread that I did not start. I think the plugs were from Baaaad. I have not posted any plug pictures. I'm sorry about adding to the confusion. This huge thread has been helpful for many of us who have chimed in here and there. Thanks to all you experts, especially PJ and LeMans Guy!



Na, sometimes a post will wiggle all over a bit, but it can add to options or what another has experienced. I only get PO'd when a reply is added that has no value or belonging as a reply to the original posted question, like if someone chimed in on this timing issue with, "Hey guys, can anyone tell me if my transmission is bad?" 

Would be really cool if we could somehow be able to create a spin-off question/post *by the same OP.* It would split the screen in half and on one side would be the original post and right next to it on the split screen would be a "parallel" post, ie Timing post/Carb post seeing it appears *Baaad65* may have 2 issues working together that both need to be addressed to bring the engine into a near perfect tune. So starting a new post would side track or get lost along the way, and we may miss something that could help and bouncing back and forth can get confusing - which takes very little to do anymore. So in this case/post, we gotta cover both a timing issue and carb/fuel delivery issue - or so it seems.

So Moderators and website developers take note. Get the IT Tech guy in here and make this happen.


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## Baaad65 (Aug 29, 2019)

Well bought a new vacuum gauge and tried it yesterday, I guess I never really paid attention to the total just watching the needle while I work the idle mixture screws so turns out I'm only getting 13.5 inches of vacuum, the 50 year old Hastings was right on too. I was getting my numbers from the console mounted gauge which turns out not to be zeroed and when I looked at a blown up picture the tick marks aren't 1 each more like .5 I think so that's kind of deceptive and their small marks. Not that this has much to do with timing just maybe more with tuning the pcv valve. Here's a picture with the car warmed up running. Guess I could used the pcv health thread too.


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## Baaad65 (Aug 29, 2019)

How much vacuum does this look like to everyone and what do you think the values of the marks are, the 0-5 look like one for one.


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## coyote595 (Dec 4, 2019)

It is reading 15, and the marks are at 0.5 increments.


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## Baaad65 (Aug 29, 2019)

Ok and the gauge is off a little so I'm getting about 13 under the hood with my new gauge, I thought 16 was a little high even with a 114 LS cam. Why Pontiac thought they needed .5 marks is beyond me.


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## armyadarkness (Dec 7, 2020)

Baaad65 said:


> Ok and the gauge is off a little so I'm getting about 13 under the hood with my new gauge, I thought 16 was a little high even with a 114 LS cam. Why Pontiac thought they needed .5 marks is beyond me.


Every little bit counts. When youre having trouble idling, you'll pray for that .5


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## Baaad65 (Aug 29, 2019)

Right? now if only I could see those little marks from the drivers seat without binoculars


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## armyadarkness (Dec 7, 2020)

Baaad65 said:


> Right? now if only I could see those little marks from the drivers seat without binoculars


You wouldnt use that gauge for tuning, anyway. It would really suck trying to turn the mixtures from the driver seat.


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## michaelfind (Dec 14, 2018)

armyadarkness said:


> You didn't add to any confusion. Everyone here is either trying to teach, trying to learn, or both. Sometimes you hear something over and over again, and it makes no sense, and then one day, poof! These discussions are healthy and an essential part of the bigger pic





PontiacJim said:


> Na, sometimes a post will wiggle all over a bit, but it can add to options or what another has experienced. I only get PO'd when a reply is added that has no value or belonging as a reply to the original posted question, like if someone chimed in on this timing issue with, "Hey guys, can anyone tell me if my transmission is bad?"
> 
> Would be really cool if we could somehow be able to create a spin-off question/post *by the same OP.* It would split the screen in half and on one side would be the original post and right next to it on the split screen would be a "parallel" post, ie Timing post/Carb post seeing it appears *Baaad65* may have 2 issues working together that both need to be addressed to bring the engine into a near perfect tune. So starting a new post would side track or get lost along the way, and we may miss something that could help and bouncing back and forth can get confusing - which takes very little to do anymore. So in this case/post, we gotta cover both a timing issue and carb/fuel delivery issue - or so it seems.
> 
> So Moderators and website developers take note. Get the IT Tech guy in here and make this happen.


Thanks for patience and grace.

BTW, my transmission has been making this noise lately...


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## Baaad65 (Aug 29, 2019)

That's what a lovely assistants for


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## armyadarkness (Dec 7, 2020)

Judginbg by the look of your car, I'll assume that your stuff is all in order, but for the record, the length, diameter, and integrity of the tubing on a vacuum gauge, all affect the ready. Unless you know for sure, I would make an attempt to verify the gauge.


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## Baaad65 (Aug 29, 2019)

Ok don't know which thread to choose so I'll go with this one, got my fittings to separate the booster from the pcv and it worked good..pcv to the carb, booster to manifold along with the advance and vacuum gauge. Tired of waiting for the rain to stop for more miles on the plugs so I went ahead re jetted the carb 74 to 75 up front 82 to 84 in back, set the base at 13° getting 25° on the can. Vacuum seemed to drop a little to about 11.5 inches but checked for leaks and all good. 🤔 now stop raining so I can drive it !


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## Baaad65 (Aug 29, 2019)

Ok got break in the weather and went for a drive, put on about 15 miles with 5 shift light passes and it stayed cool, dipstick stayed put, brakes felt better, no hesitation at all as I went from rolling to wot but seemed a little less scary or didn't put me back in the seat quite as much as I remember before. Also when you pulled up to the garage I mashed the throttle a couple times and now it has a hesitation or stutter before it really winds up kind of like a stepped affect so don't what that's about... I checked the accelerator pump arms, to much jet? I have a short video if I could figure out how to post it.


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## Baaad65 (Aug 29, 2019)

Ok got it up on YouTube under "throttle response "


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## Baaad65 (Aug 29, 2019)

What's interesting is before I took it out it was warmed up to about 170 so I tried mashing the throttle a couple times and it had no bog, sounded great but like I said just seemed to lose a little kick in the pants, should I try bigger squirters, maybe lighter advance springs, I thought putting the timing up and bigger jets it would be even better seems to have gone backwards a little. Pulled #1 plug it looked a little darker than my previous pictures, pulled one from the other side and it was lighter but I only drove about 15 miles.


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## PontiacJim (Dec 29, 2012)

Baaad65 said:


> What's interesting is before I took it out it was warmed up to about 170 so I tried mashing the throttle a couple times and it had no bog, sounded great but like I said just seemed to lose a little kick in the pants, should I try bigger squirters, maybe lighter advance springs, I thought putting the timing up and bigger jets it would be even better seems to have gone backwards a little. Pulled #1 plug it looked a little darker than my previous pictures, pulled one from the other side and it was lighter but I only drove about 15 miles.


You dropped your Initial to 13. This also means you have now dropped your Total the same amount that you took out of the Initial. May be where the power drop off comes from. Each time you re-set your Initial, you will want to check your Total mechanical advance and the RPM it comes in at - vacuum disconnected. Adjust as needed if needed.

The fuel squirters could be too rich, ie too large, or not large enough and that could also give a slight hesitation. Long accelerator pump shot may help if it is not enough fuel. Too long may be adding too much fuel and causing a bog. This is where you have to make one adjustment/change at a time and take notes.

Plugs dark on one side, less dark on the other can be fuel distribution through the manifold as they are not "tuned" to provide equal fuel to each cylinder - it is "generic" in nature unless you spend a bunch of time trying to even the air/fuel flow with contouring, fuel dams, and filling. You can try going leaner with just a smaller jet in the front side where the plug shows to be a little darker - if you want to experiment. A carb will not be that perfect as EFI and individually controlled fuel management systems.


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## Baaad65 (Aug 29, 2019)

I increased my base from 11 to 13 and didn't check my mechanical because I didn't think it would go down, the total should be up. I think it was Lemans Guy that said my secondary jets should be increased and that my squirters should be good at # 31. So why didn't I have this hesitation when I put things back together and tried it but it shows up after a drive, I didn't sit and idle a long time in the heat where the fuel might be heating up vaporizing. I only went up one drill size in the front and six in the back, just don't want to be running lean. It was good before with these squirters so I only increased advance which shouldn't give it a hesitation then changed the jets so I would think that is the problem but my plugs were pretty light with a couple showing aluminum specs so I should need to be richer especially increasing the advance right?


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## Lemans guy (Oct 14, 2014)

Your Centrifigal total is fixed it will not go up or down. When you add or subtract to base it changes “Total” not Centrifigal. If you are at 36 and go down to base to 11 then at 34 you may have a bit less punch.

yes, I did suggest to up the secondary jets, but not the primary. It looks like you upped those as well. Like PJ said when you change many things the you have to figure out which change caused the issue. I don’t get hung up on the number spread of primary vs secondary jets. Like they must be 10 apart. I have found via the AFR that sometimes that does not give the best AFR. A little deviation as long as AFR is in tune with your engine and driving actually runs better. So 72 primary and 84 secondary may be the best even if it is 12 instead of ten apart.

Just a guess when you upped both primary and secondary jets you made it too rich and you also backed it off two degrees of timing. Change one thing at a time going backwards see if you lose the hesitation. I would drop those primary’s back first.


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## PontiacJim (Dec 29, 2012)

Found this neat little site from Holley that has a ton of info that may help. You can expand the site to provide even more tips/info.

Making too many adjustments at a time only throws off what your goal is. You had higher vacuum, now that has dropped - which can affect timing/carb adjustments (and even port velocity) each time. I am not so much a fan of a double pumper as I prefer a vacuum secondary for the street as they can be a little more forgiving, responsive, and responsive to engine needs. With a double pumper, you are pushing fuel into the engine "right now" so things like converter stall and rear gearing can come into play.

Timing, vacuum, and a host of carb settings can be played with, but something as simple as the outside weather like temps/humidity can have the carb adjusted perfect one day and out of adjustment the next day - racers know this and have to constantly adjust carbs/timing, etc for such conditions. So consistency also has to be done in your testing, ie engine temps, acceleration practices. length of the power run, speeds, RPM's, etc..

Go through this site and their tips and "how to" videos which may be of help. Again, I am not a Holley guy just for the reasons you are experiencing - too many possible adjustments and tricks that you really have to be a Holley tech to understand all of them. LOL I like simple & basic adjustments.

At this point, you are see-sawing back and forth from Timing adjustments to Carb adjustments and with each of the changes you are affecting the other and then trying to compensate by going back and adjusting the other again and you may be adjusting both of these for a long time doing it this way. NOT being mean here, so don't take it personal.

Set your timing to its best possible setting and leave it alone, period. Once that is done, then go after your carb adjustments.

Get you Timing back to a base number like in the beginning, somewhere around 21-23 degrees with the vacuum can attached. 32-34 degrees Total @ 2,800 - 3,000 RPM's.

See where your engine vacuum is. With a big cam, don't expect to be able to adjust the carb air/fuel ratio as you can with a stock engine. Big cams need more idle RPM's to run well which can be related to lower engine vacuum and slower port velocity - ie the speed at which the fuel mixture is entering the engine is slow/lazy and needs to be sped up through a higher idle RPM. 750-850 RPM at idle may not work as well as 900-1,000 RPM's. So idle RPM's are another tuning measure. Of course this is where a higher stall converter is needed, if an automatic, so you can raise the idle speed without the car wanting to take off on you when in gear and you have to use both feet on the brake pedal to keep the car from lurching forward.

But your next problem with the higher idle will be when you shut the engine down. The primary throttle blades will most likely be cracked open enough that the engine vacuum will still pull gas from the idle circuits. This can lead to "dieseling" or "engine run-on" when you shut the car off. This will ultimately lead to engine damage. So if you do raise the idle RPM's, you will want to add a way to drop the idle RPM when the engine is shit down and this is often done with an electric idle solenoid switch which can be purchased aftermarket. I don't know if there is some way to adjust the Holley so this solenoid is not needed, but maybe some Holley experts will know what can be done.

I am just pointing the above out as a possible adjustment that may be used/needed with a larger cam - even Pontiac had an increased idle RPM setting on their RA IV cam with all of the overlap the RA IV cam had.

So idle speeds/idle mixture would be my first check/adjustment. Then go from there - step at a time and road test.

You may feel that the car has lost a little power/pull, but if the engine is running on the lean side, it will seem to have more peak power/pull, but you may also be at the point of melting parts. Fattening up the engine may feel like you have lost some power/pull - and you do. But you won't be melting parts. The A/F meter really is needed to inform you of how the A/F mixture s doing, and allows you to adjust each function of the carb - idle, power, cruise and dial it in with a lot less guessing and trial and error testing.

You will get it and you have already made improvements, just keep sticking with it and you will become an expert. 





__





Carburetor Technical Support - Holley







www.holley.com


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## Baaad65 (Aug 29, 2019)

Lemans guy said:


> Your Centrifigal total is fixed it will not go up or down. When you add or subtract to base it changes “Total” not Centrifigal. If you are at 36 and go down to base to 11 then at 34 you may have a bit less punch.
> 
> yes, I did suggest to up the secondary jets, but not the primary. It looks like you upped those as well. Like PJ said when you change many things the you have to figure out which change caused the issue. I don’t get hung up on the number spread of primary vs secondary jets. Like they must be 10 apart. I have found via the AFR that sometimes that does not give the best AFR. A little deviation as long as AFR is in tune with your engine and driving actually runs better. So 72 primary and 84 secondary may be the best even if it is 12 instead of ten apart.
> 
> Just a guess when you upped both primary and secondary jets you made it too rich and you also backed it off two degrees of timing. Change one thing at a time going backwards see if you lose the hesitation. I would drop those primary’s back first.


So I increased the base to 13 from 11 for 36 total so that should've upped my power and I thought I could do that with larger jetting, more gas means I could have more advance without melting anything. Then I only went up one drill size in front so do you think that little of a change would give me a hesitation if not then it's in the secondary where I went up 6 drill sizes 82 to 84 because that's the next jet size I had. I guess I can try and disable the secondarys and see if that helps. Also nothing has changed in the motor except me separating the booster from the pcv so how would I lose 2 inches of vacuum from that but I'm at 11 now on the ported side of the carb. Everywhere you read it's always the squirters are to small but mine was working great with these so I don't think it that, only thing I changed was jets but my plugs were showing lean I thought it made sense.


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## Baaad65 (Aug 29, 2019)

PontiacJim said:


> Found this neat little site from Holley that has a ton of info that may help. You can expand the site to provide even more tips/info.
> 
> Making too many adjustments at a time only throws off what your goal is. You had higher vacuum, now that has dropped - which can affect timing/carb adjustments (and even port velocity) each time. I am not so much a fan of a double pumper as I prefer a vacuum secondary for the street as they can be a little more forgiving, responsive, and responsive to engine needs. With a double pumper, you are pushing fuel into the engine "right now" so things like converter stall and rear gearing can come into play.
> 
> ...


Yes I have a bad habit of changing to many things at once but I thought in this case if I add more gas that I could and would need more advance. It's a 4 speed and I had a vacuum secondary but it had a little hesitation and less power so everything I read also the carb builder said run a DP with a stick and it made a difference but ya I was on the verge of melting stuff. How do I achieve perfect timing first if the carb is out, won't it be hard to feel? I'll check out that site and again thanks for all the help👍


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## BearGFR (Aug 25, 2008)

You can't set timing by "feel". Really getting it perfect requires precise measurements either on a dyno or at the track. However unless you're trying to cut every last hundredth of a second from your ET you don't have to be that precise. 

Open chamber factory iron heads tend to be happy in the neighborhood of 34-36 degrees total mechanical (no vacuum), closed chamber heads like the 1967 670's may like a little more. 

If you've got open chamber heads, start with a safe 34 total (without vacuum) and get the fuel mixtures right first - that means in all modes of operation from idle to launch to steady state cruise to WOT. THEN and only then optimize timing but don't expect to be able to "feel" a huge difference, that is if you can feel any difference at all. 

Fuel mixture doesn't change timing, really. Except an overly lean mixture that burns hotter, slower, and puts more heat into the chambers can cause hot spots, leading to detonation, that can lead to thinking you have to back off the timing to correct when the real problem is the lean mixture. 

Bear


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## Baaad65 (Aug 29, 2019)

I have 7K3 heads street ported to 220-240 flow, about 9.4 compression, think I'll leave the timing at 36 and put the secondarys back to 82's and watch the plugs. I can't see changing one drill size up in the primary created a hesitation but maybe...just don't want to melt anything like my dirt bike story a hundred posts back...the power is nice but it won't last.


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## BearGFR (Aug 25, 2008)

Primary or secondary jet size has nothing to do with hesitation. Hesitation (or the lack thereof) is related to the accelerator pump circuit (and on a QJet, also the air valve opening rate - and in very rare cases if the car launches "hard", fuel 'slosh' into the secondary metering rod holes).

From a standstill, if you slam the throttle all at once, what happens? Does is fall on its face instantly, or does it even for just for the tiniest fraction of a second "go", and then stumble?

Tell me again which carb you're running?

Bear


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## Baaad65 (Aug 29, 2019)

That's what I was thinking that jets shouldn't do that, the accelerator arms are adjusted good, and like I said when I put it back and stomped on it in the garage it had no hesitation so I thought great, on the test drive I would just get the clutch out and go wot and had no hesitation or nose down then back up effects just a little down on power but maybe I was feeling the lean affect. Only when I got back in the driveway I mashed it a couple times and the hesitation showed up, I have it posted on YouTube under "throttle response " It's a Quick fuel 850 QFT that's been customized buy the builder I'll post the build sheet again.


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## Baaad65 (Aug 29, 2019)

...and when I put this on last summer it ran lights out except for a couple times it had a hesitation going to wot but it was really hot and humid then and the builder said it's probably the weather that I could richen it up if it really bothered me, I know cooler drier air helps this problem.


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## Baaad65 (Aug 29, 2019)

I started playing with the carb after I happened to check the plugs which hadn't been out in a while and two of them had silver specs on them which alarmed the guys here so I got nervous about melting something and richen things up.


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## BearGFR (Aug 25, 2008)

Ah,ok. You can't determine anything by what it does sitting in your driveway in neutral. That is so unimportant that you can completely ignore it. If you want to know if your accelerator pump is set up correctly take the car out let it idle along in low gear, just as slow as you can possibly go in gear with the clutch out and then nail it and see what it does.

If you do get a hesitation under those conditions then pay attention to whether it bogs immediately or whether it starts to go for just a brief instant and then bogs. That will let you know if it wants pump shot or less.


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## Baaad65 (Aug 29, 2019)

Ya I think I was making more out it when I would mash it it the driveway, guess I was being anal about it and wanted great response all the time although sometimes it does respond great in the driveway, maybe after a drive it's just really hot. I did just check the accelerator pump adjustment on the primary and after having the bowl off it did seem to come in a little on throttle movement so I adjusted so soon as the throttle moves the pump is squirting but now I can't get a feelers gauge in when opened up all the way so don't think that's right either, isn't it supposed to be .020 ? The secondary pump I actually loosened a little but still can't get a gauge in there either when fully open so hope I don't damage the pumps.


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## Baaad65 (Aug 29, 2019)

I meant the primary was coming in a little late upon throttle movement...proof read proof read darnitt.


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## Baaad65 (Aug 29, 2019)

Did anyone get to see the video on YouTube?


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## PontiacJim (Dec 29, 2012)

"Also nothing has changed in the motor except me separating the booster from the pcv so how would I lose 2 inches of vacuum from that but I'm at 11 *now on the ported side of the carb.*"

You need to clarify this statement. Is your vacuum advance connected directly to manifold vacuum or ported? Ported is not manifold vacuum and may explain your lower vacuum reading - it is not a loss, but where you have it hooked up on the carb.


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## Baaad65 (Aug 29, 2019)

The vacuum advance is hooked to manifold like I showed in the pictures, I hook my vacuum gauge to the ported on the front of the carb for tuning, maybe my old Hastings gauge was off and I know now my console gauge is off so maybe I had 11-12 the whole time....even with a 114 LS cam 15-16 was wishful thinking.


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## Lemans guy (Oct 14, 2014)

Agree with PJ and Bear and you baad, you have done a great job, but you are over thinking and over analyzing. Your timing is right, set the base to get 32 or 34 as PJ recommended because you are concerned about detonation. Stop messing with that. It is good.

you will not satisfy yourself on whether your circuits, secondaries, squirters, main jets etc without a wide band o2 meter in the cab and a vac gauge. Then you can tune the carb and be sure.

Leave the timing and drive it move than a few throttle runs as you tweak your carb. Busy yourself with listening and checking the plugs for signs of detonation. AAs you drive and tweak the AFR you will be more sure of both and can adjust accordingly. Carb setting are not going to change your timing.

You have done good relax and enjoy driving it as you, more slowly work to get it perfect. Remember you are fine tuning, that is not done in a heated rush.


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## Baaad65 (Aug 29, 2019)

Does anyone know of a temporary AFR gauge so I can tune the carb better, I don't want a permanent one installed.


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## Baaad65 (Aug 29, 2019)

...also just a thought since my manifold vacuum is now about 11.5 would a 5.5 power valve be better than the 6.5 in it now ?


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## armyadarkness (Dec 7, 2020)

With all of the high-tech hotrod stuff on your car, I can't believe that you dont want an onboard AFR gauge.


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## Baaad65 (Aug 29, 2019)

Just thinking it's a job to install and once dialed in I don't need to watch it constantly, more of a distraction..I would put it in the glove box and pull it out when needed.


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## Lemans guy (Oct 14, 2014)

Any Wide band O2 gauge installed in just aft of the header gives the best AFR readings.

That said I also have a PLX devices remote AFR that I can stick in the tailpipe of any car and read the AFR on my iPad or iPhone while riding in the passenger seat.

All the portable meters will give you a good readout on your main jets at cruise and secondaries. The portable ones gives problems dialing in the idle circuit because they are at the tailpipe and suffer from the 02 sensor, also portable, next to the outside air.

I have found that by taking a piece of aluminum line and sticking it in the end of the innovate tailpipe mounting device, about two feet of pipe, I get the same AFR readings that I get from the wide bands permanently mounted just aft of the exhaust manifold headers…

innovat has them, FAST, PLX, not sure that you will get it cheaper than a permanent mount.

No I would leave your power valve and drive it and watch the vac gauge. When you are demanding power, below 6.5 does you AFR gauge show a richer mixture? Like 12.2?

You have to drive it awhile to see what it needs along with your driving habits.


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## Baaad65 (Aug 29, 2019)

I wonder if they make a bolt in plate for the sensor so I could just drill a hole and not have to do any welding and would I need two sensors one for each down pipe for an accurate read ?


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## Lemans guy (Oct 14, 2014)

A muffler shop will weld you in a standard 02 bung quickly and not very expensive…..near the header…just call,one and ask them how much. They do it and they have the bungs that are threaded for the 02 sensors. Much easier.


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## Lemans guy (Oct 14, 2014)

I use two, but you can use one. Maybe a little more accurate, but gauge it based on cost.


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## Lemans guy (Oct 14, 2014)

They drill a hole in the pipe near the header, weld in the 02 bung and screw in a big nut to block the hole. Then at your leisure you can add the wide and 02 sensor. Make sure it is sticking mostly vertical, angles are ok but on the top half of the pipe, and keep it away from hot pipes and oil filter etc.


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## Baaad65 (Aug 29, 2019)

I think I'll try to read the plugs first if it ever stops raining, I did notice after the jet change the fuel was at the very bottom of the sight glasses so I adjusted them up a tad also noticed the primary squirter coming in a little late on throttle shaft movement so I tweaked that still with .015 fully open so hopefully the rain stops and I can get her out. Another thing if I still have a hesitation is the pink cam is in the #1 hole position # 1,according to the chart the # 3 hole would be a bigger shot up from 30cc to 37.5 cc so we'll see...I know one thing at a time 👍


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## michaelfind (Dec 14, 2018)

Baaad65 said:


> Just thinking it's a job to install and once dialed in I don't need to watch it constantly, more of a distraction..I would put it in the glove box and pull it out when needed.


I mounted mine in the glovebox😄


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## armyadarkness (Dec 7, 2020)

Baaad65 said:


> Just thinking it's a job to install and once dialed in I don't need to watch it constantly, more of a distraction..I would put it in the glove box and pull it out when needed.


Then I'd mount it under the hood. Adds another cool show factor, and use it when diagnosing or tuning.


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## armyadarkness (Dec 7, 2020)

FYI, most all AFR companies sell a kit for mounting the 02 sensor, without welding.


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## armyadarkness (Dec 7, 2020)

Isn't this exactly opposite of what we've been discussing? It seems like the MSD example is near my setup, so why am I advancing?


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## Baaad65 (Aug 29, 2019)

Here's what I've been looking for should make it an easy installation, everyone sure I wouldn't need two sensors and the passenger side has more room so how close does this have to go to the exhaust manifold outlet ?


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## Baaad65 (Aug 29, 2019)




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## Baaad65 (Aug 29, 2019)

Also found this, any good..pretty good price.


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## armyadarkness (Dec 7, 2020)

Baaad65 said:


> Here's what I've been looking for should make it an easy installation, everyone sure I wouldn't need two sensors and the passenger side has more room so how close does this have to go to the exhaust manifold outlet ?


If your engine is maintained, then you shouldnt need two. Two is optimal, obviously, but unless something is drastically wrong with your engine, the mixture should be the same on both banks. Ive never used two. 

They used to need to be very close, because they needed to reach a certain temperature before they would work, but now theyre heated. If you have headers, put them in the collector, if manifolds about 10" down


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## armyadarkness (Dec 7, 2020)

BTW, the instructions that come with your gauge will tell you where to mount.


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## armyadarkness (Dec 7, 2020)

Baaad65 said:


> Also found this, any good..pretty good price.
> View attachment 143885


Personally, I'd get the AEM. It's pretty much the industry standard/ what most guys here use.


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## Baaad65 (Aug 29, 2019)

Sounds good, I'll look around some more...what about mounting it horizontally in the down pipe before it flattens out, would be about 6" down from the manifold.


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## armyadarkness (Dec 7, 2020)

You definitely dont want it horizontal. All of the condensation and crap in your exhaust will settle in your 02 sensor. Always give it some vertical pitch so that it drains when you shut off your car


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## Lemans guy (Oct 14, 2014)

Those charts are useless, too general, high low rich lean???

optimal timing like it said in the bottom narrative is two degrees below detonation. That gives max power without engine damage. Leaner mixtures 13’s and up require more spark lead to ignite efficiently….those mixtures should be when vacumn signal is high, as throttle is mostly closed at idle and light throttle cruise.

For power demand, throttle opens more a richer mixture happens via accelerator pump, power valve, main jets and secondaries….that richer mixture needs less spark, and vacumn is dropping….vac timing is dropping…..then when throttle is at WOT there is no vac advance and the mixture should be rich, like 12.2 AFR and the advance 2 degrees below detonation…usually 36 degrees sometimes 34 or 32…..some engines actually take 38 or 40 but be careful as you are close to detonation territory.


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## Lemans guy (Oct 14, 2014)

One thing is don’t try to tune a carb to exactly “stoich”14.7 for pure, 14.1 for 10% ethanol,..it is too lean. Carbs are wet intakes and gas adheres to and puddles on the intake runners. They are not quite as “technically efficient” as fuel injection, but can run just as good.

stoich is a perfect burn of all fuel molecules, even though 13’s are on the rich side of stoich, it is still a lean mixture,…with low 12’s being rich……


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## Baaad65 (Aug 29, 2019)

How's this one?


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## Lemans guy (Oct 14, 2014)

It will work, just need a bung in the exhaust near the header…


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## Baaad65 (Aug 29, 2019)

Or there's this model, didn't research the differences and found this bung clamp.


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## armyadarkness (Dec 7, 2020)

Lemans guy said:


> One thing is don’t try to tune a carb to exactly “stoich”14.7 for pure, 14.1 for 10% ethanol,..it is too lean. Carbs are wet intakes and gas adheres to and puddles on the intake runners. They are not quite as “technically efficient” as fuel injection, but can run just as good.
> 
> stoich is a perfect burn of all fuel molecules, even though 13’s are on the rich side of stoich, it is still a lean mixture,…with low 12’s being rich……


This is my issue. My car runs strong and healthy as an ox, but it lost a lot of power and the mid range is sluggish. All aspects of it are sound, milage is horrid, AFR's sre in the 13's, so the only thing left to assume is that it's rich.


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## Lemans guy (Oct 14, 2014)

Cruise should be in the 13’s ……and idle too. The idle circuit and main jets should allow cruising there. When you power down, quickly accelerator pump shot should change that mixture to rich 12.2…or close

When you demand a constant power, like pulling a grade sat at 45 or 50 mph, you should not have secondaries on and you are past time for accelerator pump….

let’s use a Holley quick fuel carb as an example

Now the power valve should deliver that 12.2..richer mixture. It does not come on until it’s rated number. So if you are running a 6.5 HG power valve once there it opens, it does deliver a gradual mixture, it is open or closed and the two POWER valve channel restrictors flow fuel

Your vac can on the dizzy is now seeing below 6.5 vac it has dropped much of it’s 10 degree advance, it is gradual and like I set em starts pulling at about 5HG and gradually pulls in that 10 degrees until about 11 to 13 HG. So below 6.5 HG you are into a richer mixture, your vac timing is mostly out and your Centrifigal timing is coming up and set for a richer mixture..

yours rods have to be the ones that deliver that richer micher on demand without secondary engagement, secondaries come on when the throttle plate opens much wider, so sometimes the in between is too lean…..


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## Lemans guy (Oct 14, 2014)

Typo…the power valve does NOT deliver a gradual mixture..it is open or closed.


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## armyadarkness (Dec 7, 2020)

I did have my pump shot set to the weakest setting (of the three), AND... I just realized that the Summit diizzy is set to be all in at around 4500 or higher. That may not be helping.


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## Lemans guy (Oct 14, 2014)

That 4500 number is dragging you down, get that down to 3000 and definitely up the pump shot


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## Lemans guy (Oct 14, 2014)

If you are running pure gas with 14.7 stoich you can run idle circuit and even light throttle a tad leaner, like 14.2 ……. .5 richer than Stoich. If. You are running 10% ethanol with a 14.2 stoich a .5 richer is 13.7 .

if you go too lean you risk backfire on deceleration as that throttle closes fast the AFR spikes lean normally….so the leaner that you run the higher that spike is. If you watch an AFR meter as you drive it is easy to see.

These numbers are not exact there the center of say a .5 range where on 10%, 13.5 or 13.9 is OK.


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## armyadarkness (Dec 7, 2020)

For the record, although I've had an AFR meter on all of my hotrods, for more than 20 years, Ive never used one to set idle mixture. I ALWAYS use vacuum.


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## armyadarkness (Dec 7, 2020)

even using the lightest springs they give, it's still 3200 all in


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## BearGFR (Aug 25, 2008)

armyadarkness said:


> even using the lightest springs they give, it's still 3200 all in


Swap to heavier weights.


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## armyadarkness (Dec 7, 2020)

BearGFR said:


> Swap to heavier weights.


Man I'm going to need a bigger brain for all of the stuff I'm learning here!


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## Lemans guy (Oct 14, 2014)

Vacumn is orbit why not use both? If your Vacumn method is right your AFR should be right as well…


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## Lemans guy (Oct 14, 2014)

Sorry, my iPad spell corrects….not orbit….alright


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## 67ventwindow (Mar 3, 2020)

One thing about AEM,the gauges I have seen have provision for data logger. I like to make changes because of repeated performance than one run. If your geeky enough there are projects that use controllers to link AFR, TPS. Tach and GPS for data logging and near real time display .so you can get a better picture of what your car is doing when.


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## michaelfind (Dec 14, 2018)

Lemans guy said:


> Sorry, my iPad spell corrects….not orbit….alright


Local sign had this on it, “autocorrect made me say things I didn’t Nintendo “


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## Baaad65 (Aug 29, 2019)

So fired the car up tonight after adjusting the accelerator pump arm after having the bowls off for the jet change and bumped the floats up so they're at a third up the sight glass, getting a solid 12 inches sometimes 12.5 but a pretty steady needle, base still at 13° - 36° in @ about 2850rpms, 25° on the can so now I'm getting 12° from the can with a lock washer and a drop of superglue over the screw(directions said purple thread locker but I wanted to be able to get it loose if I had to) so got it to temperature then started stabbing the primary's and it sounded good, then laid into the secondarys once I think, responded great mashed the pedal again from idle big backfire and flame uh oh...this is with no air cleaner so I move the primary pink cam to cam hole #3 linkage hole #2 try it again, perfect no hesitation no bbq, perfect three more times. Only problem with I didn't get it out for a test drive hopefully tomorrow or Saturday. So should I be concerned about the carb back fire just one time, seems like that happened once before a long time ago. Also I can't find much information on the pink cam position I'm using now just that number one is 30cc shot and number two is 37.5 shot, the charts show what I have it set for is a little more aggressive and longer shot, I'm running #31 nozzles and do you think I should run the secondarys in the same position since maybe that's where I could have been lean causing the back fire? Guess it's all hinges on the drive and the plugs after about 50 miles.


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## Lemans guy (Oct 14, 2014)

Sounds like you fixed the spitting thru the carb, which can be caused be a late pump shot, and especially if your engine was cold. I would not change anything right now. You tried it twice it did not cause spitting thru the carb.

Also I would slow down always banging the throttle to max multiple times at idle. If you did this on a cold engine it is not really good, you could get coughing thru the carb just because it is cold. Maybe you were at hot idle then, but just note that.

You have done great, just drive it normally, not pounding it all the time. Get to know how it feels and make changes slowly…..enjoy it,

Remmber racers have to hammer their cars all the time, what happens they have to repair them all the time too. They are pros, experts, and can swap stuff at the track faster than you can. That is built in to their plans…you don’t have to do that. So slow down a tad. Your set up sounds really good…


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## Baaad65 (Aug 29, 2019)

It was at normal temperature I wouldn't do anything cold, and I know Bear said not to be concerned about how it performs in the driveway but I don't think anyone would like their car to stumble and definitely not backfire in the driveway but be fine on the road so that's what I was trying to solve. If it's good standing still it should be good driving it I'm thinking. I'll drive it now and decide if I should adjust the secondary cam.


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## Baaad65 (Aug 29, 2019)

I put a message into Holley tech about the pink cam position but if anyone has any information on that I would appreciate it. It still is concerning that I got a carb backfire after raising the floats and adjusting the accelerator correctly and why only once?


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## Baaad65 (Aug 29, 2019)

Also, (I know I'm a pita) but should I be concerned about the vac can giving 12° now even though it was locked and glued so now my advance timing is 25° ?


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## Lemans guy (Oct 14, 2014)

No 12 is fine and so is 25….I set them at 8 to 12, most at 10…the 12 does not add to your total timing and 48 degrees max for light throttle is fine….46 to 48 is right no more…

you are not a pain….just fine tuning, I think that you fixed the pump shot mostly, and those cams are always trial and error…

Once you have the AFR gauge and are driving you can watch the pump shot as the gauge drops rich so you will know exactly what you are getting


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## Baaad65 (Aug 29, 2019)

Thanks! Hopefully I'll get some windshield time this weekend and start by checking the plugs that's if my new brake line leak doesn't get worse...another thread 🤯


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## Baaad65 (Aug 29, 2019)

So I thought I would go back to this thread because it was about timing, I haven't heard back from 4 seconds flat about my questions about the plugs but I was thinking about what he wanted me to do with the advance. So he wanted me to go with the bigger bushing 18 and more base timing so my question is does it matter how you get to 36 degrees ? Either the 23 bushing and 13 base or 18 bushing and 18 distributor advance. This is keeping the vacuum advance at 10-12 degrees, I'm trying to get the most bang for the buck when I hit the go pedal with of course not detonating, guess I'm getting used the horse power and wanting a little more but don't know if there's anything left to squeeze out of this motor unless I start making major changes but any ideas are certainly welcome.


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## BearGFR (Aug 25, 2008)

First, the vacuum can has nothing, nada, zilch, zero, NO impact on what happens when you "hit the go pedal" because when you do that, vacuum drops to zero and the can is out of the picture. The can is only active when you're "driving sedately" and don't have your big toe hanging over into the carburetor.

None of the changes you're talking about with regard to timing will make enough difference for you to feel in the seat of your pants. You might be able to tell a difference on a drag strip with their accurate to .001 timing clocks - maybe. 

If it were my car I'd probably start with 18/18 just because 23 initial "sounds like" a lot and is more likely to make it harder to start, especially when it's hot.

If you're looking for changes you can actually feel, you won't find them there unless you happen to pick a combination that your engine just HATES and it gets much worse.

Bear


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## Lemans guy (Oct 14, 2014)

Exactly right!…..set many up 18 and 18 and 10 degree of vac. 28 for idle timing then. The reason many like this is because race shops do this when they have no vacumn advance. This way they get enough, just enough, idle timing at 18 to smooth it, and keep 36 total.

There is no great advantage here, especially if you use 10 degrees of vac advance hooked to full manifold vac. Here is why, The right set-up can give you more than 18 degrees idle timing with vac advance.

like 14 base + 10 vac for 24 @ idle….add in 22 degrees Centrifugal for 36 total…..24 with a medium hot cam will be better than 18 base……..

Also, that 18 and 18 some argue for on a medium cam, which most run, does not really do anything more because as soon as you barely move the pedal you start to pick up Centrifigal timing,…remember it is based on RPM’s. I think you get a smoother transition with Centrifugal timing climbing at the same time as vac timing dropping out. Either way the difference is not that great.

stock cam idle,….I set in low 20’s with 10 degree vac….

Medium lope/ increased duration over stock….I set in mid twenties at idle with 10 from vac

Radical duration, some rollers with like 8 Hg vacumn…I set in high twenties, even low 30’s with 10 degree vac..

just a guide each engine is different, each combo unique. But 18 and 18 is not a manic number,…..just used a lot to take out Vac advance….which is a bad idea on a street car.


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## Baaad65 (Aug 29, 2019)

Ok, I know the vac advance drops out right away, when I started this I had the 18° bushing in and base at 19° without the vacuum can so I added it and you said use the 23° bushing and 13° base now are you saying I should go back to the 18° bushing and 18° base with the vacuum advance limited to 10°? Never had a problem starting I just saw a couple plugs with silver specs on them but that's before I richened the carb up. Again does it matter how you get to 36 total between the bushing and distributor advance, is one way better? Is 18° and 18° the happy medium? Also moved my secondary pink cam to the #2 hole second position like the Holley tech said I could try before the change out the squirters, let it get up to 180 and no hesitation mashing the throttle in the garage but it's bad weather here so no test drive.


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## Lemans guy (Oct 14, 2014)

No Re read my post, I am not saying 18 and 18 is great, yours in my view is best 23 and 13 base…with 10 vac for 23 at idle and 36 total. I would leave that. What amI saying is some guys insist that more base timing is better… they want 18 or 23 base…or whatever because a racer told them to. The point is they do that because often they use no vac adance so they have to have more base timing to get a smooth idle.

I think your hesitation is the accelerator pump cam and squirter like PJ pointed out.

does it matter how you get there to 36. 36 is the most central number where most of these V8’s run best for total timing. Actually of course it is a range from 32 to 40 most cars run best at 36, but some take more and some take less. If it is pinging you need less,32 is conservative 40 is detonation territory.

so it is with base and Centrifigal can you have 4 degrees base and 32 Centrifigal? Yes many cars, V8’s came from the factory that was to retard idle timing and burn off emissions…can you run 30 base like some racers say, or weld your distributor in at 36 base. Yes?

Maybe some super drag car needs that, but again timing is a range and an orchestra, where you are not for street performance is great, you can keep moving it around but not sure what will be achieved. Hope that helps.

each engine is a tad different, each driver has different goals and styles.so there is no one absolute.


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## Lemans guy (Oct 14, 2014)

I would leave your timing where it is and drive it…..should run great


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## Baaad65 (Aug 29, 2019)

Got it, waiting for decent weather so I can see how moving the pump cam affected things then maybe change the the squirter or maybe both squirters idk if they should be changed in pairs or just a trial and error thing, thanks again 👍


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## Baaad65 (Aug 29, 2019)

...and here's what that 4 seconds flat site suggested to do but still haven't heard back from them on my follow up email.


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## BearGFR (Aug 25, 2008)

How it acts sitting in your driveway in neutral tells you nothing about how it will act under load. Trying to tune by what it does sitting in neutral will only end up with you chasing your tail. and not getting anywhere.


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## Baaad65 (Aug 29, 2019)

I get that but I still don't think it should have a hesitation anytime when you punch it, driveway or dragstrip..just my line of thinking I guess.


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## BearGFR (Aug 25, 2008)

Think about it.

Sitting in neutral, how much load is on the engine? Very little. When you open the throttle, there's nothing "holding it back" except for its own internal friction so it's going to be able to rev much more quickly. So how much extra fuel is it going to need in order to 'carry it through' the transition period when the throttle opens suddenly but before the air flow through the carb "catches up" and starts pulling fuel from the primary circuit? Not much.

Contrast that to when it's under load, pulling hard through the entire drive train and against the pavement, trying to overcome inertia. It's not going to be able to 'spin up' as easily because of all the forces that are trying to hold it back. RPM isn't going to ramp up as quickly, so air flow is not going to ramp up as quickly, and the primary circuit in the carb isn't going to come online as soon. The engine is going to need more fuel, more "pump shot" to carry it through until they do.

Setting up the pump shot volume, timing, and duration to be "perfect" for it sitting in your driveway is very likely to be too lean for actual driving conditions and you're going to have a lean bog while driving. Conversely, the right settings for driving might be too much/too rich for when it's just sitting and you may have a 'rich bog' then.

Pick one. Which situation is the more important?

Bear


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## Baaad65 (Aug 29, 2019)

Well I just talked to Don at 4secondsflat or FOB ignition systems for 30 minutes and first of all he says MSD distributors are Chinese garbage now but likes the Petronix, he still insists on a 14 degree bushing (which the lowest I have is 18) with 20 degrees of distributor advance for 34 @ 3200 rpm and 10-12 vacuum advance but says my MSD vacuum can won't work...and says 30-40 degrees at idle will burn the residue fuel, keeping the plugs nice less junk in the intake and is ok because there is no heat and pressure at idle. So idk I guess I can try that and he wants to see the plugs after 200 miles, also said because it's a manual that the advance has to start over on every shift, so does that make sense because it's different than what everyone is saying here.


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## Baaad65 (Aug 29, 2019)

That's FBO and Pertronix sorry.


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## BearGFR (Aug 25, 2008)

> because it's a manual that the advance has to start over on every shift


The man's an idiot.  Don't let him touch your car again - ever. 40 degrees at idle to keep your plugs clean??!!!?? Good grief!!! 

Centrifugal/mechanical advance is controlled by RPM, >>AS IT SHOUILD BE<<, so yeah, if you let the engine drop back to idle RPM between shifts, then the advance will follow RPM - >>LIKE IT'S SUPPOSED TO<<.

You can listen to him if you want to, but everyone here has been bending over backwards to try to help and I know a lot of folks have really put a lot of effort in trying to help you understand all this. But hey, it's your car and you can do with it as you please. Best of luck.

Bear


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## Baaad65 (Aug 29, 2019)

Well PJ put me on to this site and LeMans guy has his book so I thought it was reputable and I've read everything on his site and talked to him and he doesn't sound like an idiot he's been doing this for 50 years. Maybe others can read his tech articles and see what they think or call him up and talk to him, I'm not saying he's the last word in tuning just trying to understand everything and maybe see if his ideas work, but I really don't think he's some google moron. Also all the information was getting confusing so maybe I got the 40° idle advance wrong.


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## Lemans guy (Oct 14, 2014)

If you set idle timing at 30 as he asked with a 14 Bushing as he said that is 44 degrees of total timing….if you drive 200 miles with 44 degreees of total timing the detonation in your engine will be extreme. Ask these engine builders, PJ, Bear, what your bearings will look like then.

All for the purpose of reading spark plugs, to see what your timing should be. That is what your timing light does. You should read plugs also but not cause severe detonation to do it.

Don’t be the guy who wins a million in the casino, but keeps playing in search of more, and then loses it all. You have a million now.


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## Lemans guy (Oct 14, 2014)

His 34 degrees of timing and 10 to 12 vacumn is exactly or very close to what we all have been saying. Nothing wrong with that. His other change is why racers often do run up the base timing, he said 20 base + 14 Centrifigal. Your car will ok there. It is still 34 total. It will not be that better or worse than where you are. So all that works.

The 30 base + 14 Centrifigal for 44 total and then a 200 mile drive to burn off fuel and read plugs seems to be a bad idea.

I do have his book he is a racer a good one, but racers go to extremes to win and cut seconds and tenths of seconds and they change cams easier than you change your pants, so just understand the level of stuff they live with. Blew the bearings, no big deal, pull it out and throw in a new crank, nothing slows them down. That is their world. It does not mean they don’t have great skills and tips. But don’t forget you are not a pro racer, or maybe you want to work toward that.


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## Baaad65 (Aug 29, 2019)

He said set the base at 30 only for a vacuum read then set to 20 with a 14 bushing = 34 and 10-12 vacuum advance, I was confused too with that email but now it makes sense and the higher advance will only be at idle so when I crack the throttle that 10-12 goes away and I'm right where I should be right?


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## Baaad65 (Aug 29, 2019)

...also told him this is a street car never been raced so he knows I'm not prepping this for racing.


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## Lemans guy (Oct 14, 2014)

If you set the base at 20 and add 10 or 12 vacumn for 30, 32 idle……you can do that. The vacumn does not go away instantly, it drops out as the throttle opens…..Centrifigal timing goes up…..Vacumn timing goes down.

If that is what he means then again not a few degrees difference than what we have talked about here, I told you that I have set up many at 18 + 18…..he says run 20 + 14…that is a 2 degree difference…..and and a few degrees anyway in the end…..

none of that will hurt your engine, but not 30 base and 14 Centrifigal…don’t do that.


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## armyadarkness (Dec 7, 2020)

All I have to say about it is that you really have to stick to one school of thought. You can't simply pick and choose the procedures that you like, from different approaches to tuning. No one here would be offended if you chose to take someone elses advice, but EVERYONE here is going to be frustrated when they hear that you've not followed their advice, are still asking for it, and have yet to resolve your tuning.

I don't know half of what these guys know, but I'm a scientist and an engineer, and I try to help everyone here by being available daily, even if Im just throwing crap at the wall until something sticks.

The Wagner valve is a perfect example. You took the advice, followed through with the education and tuning, but then stopped at the catch can... Only to come back two weeks later and wonder why you had oil in your intake. I'm not angry that you didn't take our advice, Im frustrated that you didn't and now your experiencing problems that we tried to help you avoid.


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## Baaad65 (Aug 29, 2019)

Lemans guy said:


> If you set the base at 20 and add 10 or 12 vacumn for 30, 32 idle……you can do that. The vacumn does not go away instantly, it drops out as the throttle opens…..Centrifigal timing goes up…..Vacumn timing goes down.
> 
> If that is what he means then again not a few degrees difference than what we have talked about here, I told you that I have set up many at 18 + 18…..he says run 20 + 14…that is a 2 degree difference…..and and a few degrees anyway in the end…..
> 
> none of that will hurt your engine, but not 30 base and 14 Centrifigal…don’t do that.


No I would never keep it at 30 I'm not that dumb but some might disagree, I think he wants more base to burn off the fuel and oil fumes and says it should fire up on the first compression stroke because I questioned it too as what is the difference if I have a large bushing or small bushing and a lot of base timing or a little as long as I hit the 34-36 mark...that should be all covered in the book you have and think I'm going to order one.


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## Baaad65 (Aug 29, 2019)

armyadarkness said:


> All I have to say about it is that you really have to stick to one school of thought. You can't simply pick and choose the procedures that you like, from different approaches to tuning. No one here would be offended if you chose to take someone elses advice, but EVERYONE here is going to be frustrated when they hear that you've not followed their advice, are still asking for it, and have yet to resolve your tuning.
> 
> I don't know half of what these guys know, but I'm a scientist and an engineer, and I try to help everyone here by being available daily, even if Im just throwing crap at the wall until something sticks.
> 
> The Wagner valve is a perfect example. You took the advice, followed through with the education and tuning, but then stopped at the catch can... Only to come back two weeks later and wonder why you had oil in your intake. I'm not angry that you didn't take our advice, Im frustrated that you didn't and now your experiencing problems that we tried to help you avoid.


First of all I really do appreciate all the help and education because I certainly am learning a lot and god knows I need it, I'm just weighing everyone's opinion that's smarter than me and have always questioned things until I understand them and sometimes that gets peoples underwear in a not but didn't me to do that. You guys have a lot more experience and knowledge than I do but I also think this Don does too I don't thinks he's not an idiot. It won't hurt to do some trial and error to see what works best as long as I don't do something really stupid. Also I never said I had oil in the intake and still don't just on the plugs and maybe because the were a step colder and maybe because my base timing wasn't high enough idk, but does every car you see have a catch can? I've been to a lot of shows and have seen a ton of cars this year and very few had cans and if can figure out a clean way of doing it I will maybe over the winter but it's not high on my list like a heater core and vent window rubber.


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## BearGFR (Aug 25, 2008)

Baaad65 said:


> Well PJ put me on to this site and LeMans guy has his book so I thought it was reputable and I've read everything on his site and talked to him and he doesn't sound like an idiot he's been doing this for 50 years. Maybe others can read his tech articles and see what they think or call him up and talk to him, I'm not saying he's the last word in tuning just trying to understand everything and maybe see if his ideas work, but I really don't think he's some google moron. Also all the information was getting confusing so maybe I got the 40° idle advance wrong.


Maybe I misunderstood what he was telling you to do. When I read that response it just sounded like a TON of timing to me, and running a bunch of initial lead "just to keep the plugs clean" sounds like a load of you-know-what.

Bear


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## Baaad65 (Aug 29, 2019)

BearGFR said:


> Maybe I misunderstood what he was telling you to do. When I read that response it just sounded like a TON of timing to me, and running a bunch of initial lead "just to keep the plugs clean" sounds like a load of you-know-what.
> 
> Bear


Believe me when I saw his email I thought it he was nuts too until I talked to him, but I still don't understand why putting the base timing to 30 degrees and lowering the idle to normal increases the vacuum reading, I thought the cam and other components determined engine vacuum. He just wants to get a vacuum reading for tuning purposes at that timing degree. Also sounds like I need a better vacuum advance can than the MSD which we talked about that just putting a limiter on it isn't good enough that the vacuum signal or something that was brought up in this thread that I can't remember isn't good on regular cans, I have the VC181 but would need the Lars limiter...unless I scrap the whole distributor since it does have a relucter paddle piece broke off and get a Pertronix Ignitor III with the adjustable vacuum advance.


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## PontiacJim (Dec 29, 2012)

If you doubt yourself and then start looking/hearing/feeling "things" coming from your engine/car, you are apt to find them and then this adds to your doubts and then you begin to doubt those who try to help you and you question their answers and then look to others for their answers then you adjust your engine/car to what they suggest thinking they have the solution but when it still seems off or does not work, your doubts are renewed and you then look to the next guy for his answer and experiences and now all you have done is forget your settings, which are now all over the place, and which further add to not only your frustrations, but to your doubts. Continue this path and you may damage the engine, then you will be looking for a "fall guy" to throw under the bus because it's hard to accept the consequences of your doubts that led to your engine damages.

The other thing is that just because some guy is a "professional" racer, engine builder, book publisher, does not mean that he has the answer to *your *engine build setting between the frame rails of your car. He is not by your side adjusting the tune with you - but we are each time you take the car for a drive and report back. It is fine to seek opinions from others, and if reputation has a lot of weight with your engine adjustments, then stick to what he is saying and do not cloud it up with the advice given here on the forum - use one or the other and follow through with it. IF it does not work out, then break clean of whatever settings you did have, and start fresh from square 1 with the other guys settings. No harm or foul in doing that - it is your car and we ALL understand you want to have it running peak. But blending several tunes and adjustments and trying to take the best of what one guy says and the best of what the other guys says won't work.

Many of us have been on the forum quite a while and have seen many engines and tune-up/timing/carb settings and have done our best to help and get those items all in sync. Noboby knows it all and every engine build/car is different. WE offer the best knowledge about these cars as we can, but for most of us, it is our hobby and not our living. If a "more professional" guy who does this for a living can offer better advice, I don't think any of us are insulted, but you want to follow through with that "professionals" advice and forget what some of us have offered up in helping you with your situation. Let us know your end results as per the "professional" as we are all open to learning just another kernel of information that can be used to help others who will come to the forums. But again, stick to one set of advice and guidance values or the other, not both or a mix, because your doubts and confusion only add to out frustrations and throwing our hands up and waving the white flag.

None of us want to see you damage your engine with bad, or misunderstood, advice/settings.


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## Baaad65 (Aug 29, 2019)

Thanks for that and I really do appreciate everyone's advice because you know more than me, you suggested the FBO site otherwise I would have never heard about it and so I read all the tech articles and they seemed pretty knowledgeable so I just bounced his ideas off of this site to see if you agreed with any of his thinking and it sounded like I insulted everyone's intelligence which in no way wanted to do. I feel like I have a family of people with the same interests..it's my Fakebook. I document every change and the car runs good I just want it to be at its peak with everything without damage and I've only looked here and now at FBO for advice, I'm not reading every Google story and trying that but I might try what this guy recommends and hey if it isn't better I'll be the first one to say his tune didn't work and your guys tune did believe me! Also if you haven't guessed I'm a little hyper and fidget with things too much, it's a problem I know, been that way all my 56 years..probably not going to change now just hope it doesn't bite me 👍


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