# Clicking noise 1970 400 in 68 GTO



## 1968GTOMAN (Aug 3, 2020)

Hello,
I received this car from a dealer out of state. When it came on the tow trailer i immediately noticed a clicking noise in upper part of engine.
Oil pressure about 9 PSI at idle 
60 PSI Avg while driving.
I've had the car to a mechanic and he took the valve covers off and saw nothing wrong so I took it to a boutique type shop which works only on classic cars and I'm waiting for an answer from them for a week now.
I changed the fuel pump because it went bad, and when i bought the new one i made sure it wasn't one with a loose arm because when there is no spring on the arm of a fuel pump they can rattle and clank. So its not that but has that type of sound, like metal clanking.
I've been frustrated by the horrible noise, but car runs like a champ., ive actually been toying with the idea that maybe there's something wrong with the distributor shaft which is affecting the oil pump but thats not substantiated by anything but my guesswork. There is some oil under inside the valve covers, i can see it through the breather and oil fill. So some oil is getting up there.
Anybody have any ideas?
Thanks!
Bill


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## pontrc (Mar 18, 2020)

Sounds like to me a collapsed lifter which is annoying. What alarms me is the pressure at idle. Is this a factory gauge or mechanical?


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## 1968GTOMAN (Aug 3, 2020)

Thanks, its an aftermarket mechanical gauge.
When i first start the car its up in the 50 to 60 PSI range in idle then as it warms
up I get down the road it drops to 5 to 9PSI at idle.


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## GTO44 (Apr 11, 2016)

1968GTOMAN said:


> it drops to 5 to 9PSI at idle.


this would scare me


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## 1968GTOMAN (Aug 3, 2020)

Yeah, thats probably causing the clicking sound, but my mechsnic thinks its because when they put a cam in they didnt put the extra parts that go with the cam so he thinks its not oiling enough. Its in a shop now, hopefully they find me the answer.


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## BLK69JUDGE (Jun 10, 2010)

at what rpm does the oil pressure pop above 15 or 20 lbs...
what rpm is the engine at an idle now after it warms up ?
have you had the oil changed ? what oil filter are you running ?
no kinks in the mechanical gauge hose? what brand of gauge ?


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## pontrc (Mar 18, 2020)

You mentioned it started this off the trailer,I hope you inspected it before you bought it or hired someone to look at it. It is good advice to do this before committing. I’m sorry man hope it works out for you


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## 1968GTOMAN (Aug 3, 2020)

I didnt have anyone look, i trusted the company because they seemed like specialists in Classic Cars, on their website had a bunch of pics of the car, video, but they cleverly hid this and the gaps in the fenders.
I got them to give me a check for $2k back, that might help some but not near what im facing.
The car is very beautiful, cant deny that, its worth figuring this stuff out. I really like the car but spent alot on it. Traded in my (73 needed bodywork and paint )Charger with rebuilt 440, and $15k.
Bill


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## pontrc (Mar 18, 2020)

I’m sorry 68 never trust a dealer, too many people get burned by this, too much money to risk


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## 1968GTOMAN (Aug 3, 2020)

BLK69JUDGE said:


> at what rpm does the oil pressure pop above 15 or 20 lbs...
> what rpm is the engine at an idle now after it warms up ?
> have you had the oil changed ? what oil filter are you running ?
> no kinks in the mechanical gauge hose? what brand of gauge ?


Hi, my tach isnt hooked up yet so can provide exact RPMS. Have not changed oil yet. Car is in a shop so cant see what brand of gauge, didnt think to look for kinks.


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## Lemans guy (Oct 14, 2014)

You might need a different viscosity motor oil, hot oil at 9 or 10 PSI with a 750 Idle would be fine...5 not so much...

you are 60 Psi at speed so the pump is increasing and decreasing with RPM’s which is correct...rule of thumb is every 1000 RPM would be 10 PSI....2000 RPM 20 PSI...when hot until the pump limit....or a little more...

I would run a different oil, the clacking has so many variables but it may be a lifter...


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## O52 (Jan 27, 2019)

Use 10-30 Dino oil, not synthetic.


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## 1968GTOMAN (Aug 3, 2020)

Thank you this is very interesting and helpful!
I bought 10w40 to change it when i get car back. Someone said put 20w50 in but I argued that might slow the the flow, not increase it.


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## PontiacJim (Dec 29, 2012)

Could be as simple as a rocker arm has backed off. Pontiac torque's the rocker arm nut to 20-25 ft lbs. If the nut backs off, you will here the clicking and it can effect oil pressure.

Do not use 20W-50. 10W-30 or seeing it is summer, 15W-40 would be OK. Pontiac rates their oil pressure as 60 PSI @ 2,600 RPM's. 5 PSI is bad. 10 PSI might be marginal. As pointed out, too low of an RPM will see low oil pressure - so know what RPM the engine is idling.

A ticking noise can also be a bad exhaust gasket/ exhaust leak.


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## 1968GTOMAN (Aug 3, 2020)

Thank you! I do know that when engine warms up, idle will drop very low, maybe thats part of that oil pressure issue. These other things, my mechanic must have checked rocker arms i would think. Ill ask him when i drop my other car off to be fixed there tomorrow.
Thank you!!


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## Old Man Taylor (May 9, 2011)

My shop manual for the 64 GTO shows 30-40 psi at 2600 RPM. The RAIV would be more. I have a '69 manual, but it's not currently accessible.


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## 1968GTOMAN (Aug 3, 2020)

Hmmmmm... i wish i had a tach reading to share. Seems to be the center of the question.


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## 1968GTOMAN (Aug 3, 2020)

I should be getting a phonecall any day now from the repair shop its in. I will definitely share the results they ascertain.
Thank you for taking the time to help!


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## Lemans guy (Oct 14, 2014)

You can also just use a clip on Rpm meter to test and lots of timing lights have RPM readings as well....one in the cab is best, it can be mounted anywhere. Back in the day lots of guys clamped them on the column. Not original factory, but still old school period correct!


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## 1968GTOMAN (Aug 3, 2020)

Yes! Lol, ive seen plenty with them strapped to steering column. Years ago, i had a clock blank in my 71 Cutlass, put one on there, fit perfectly, almost looked factory.
I have a hood tach i just bought and painted to replace the old one. When the repair shop releases my car to me that's the first thing i plan on doing.
Thanks!


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## PontiacJim (Dec 29, 2012)

Old Man Taylor said:


> My shop manual for the 64 GTO shows 30-40 psi at 2600 RPM. The RAIV would be more. I have a '69 manual, but it's not currently accessible.


You are correct. The AMA specifications show that the pump pressure was upped in 1965 for the GTO and other Hi-Po engines to 45-50 PSI @ 2,600 RPM's. The standard Tempest/Lemans/Full sized cars still used the 40 PSI pump - and the economy engine option in the GTO.

It is not until 1967 that the 55-60 PSI pump @ 2,600 RPM's is seen in the AMA specifications. The RA IV used the 60 PSI pump. Of note is that the AMA specs for oil list the Single Viscosity oil for above +32 degrees for the RAIV as 30W, as opposed to 20W for the non-RAIV, with the acceptable alternate viscosity for both the GTO/RAIV as 10w-30, and 10W-40 as an alternative only with the RAIV option.

For 1970, we have a few changes. The GTO still uses the 55-60 PSI pump, the RAIV require SAE 30W or 10W-40 at all times, and the optional 400 4-Bbl (Tempest, Lemans, Lemans Sport, etc.) got the 30-40 PSI @ 2,600 RPM oil pump while the optional 455 4-bbl got the 55-60 PSI oil pump.

For 1971 it is a repeat as above less the RAIV engine.

1972 shows 30-40PSI for the standard 400, 55-60 PSI on the 400 4-Bbl option, 30-40 PSI on the standard 455 and 55-60PSI on the 455HO.

The only engine to use a higher pump pressure, that I am aware of, was the SD engines at 80 PSI. In the late 70's when the HP went down the tubes, Pontiac went back to the 40 PSI pumps again until they began to have engine failures on the 6.6 TA engines. Those engines that got out the door were recalled and retrofitted under warranty with the 60 PSI oil pumps and the oil pan with the factory oil pan baffle. Engines following those that got out the door were all factory equipped at the asembly plant from that point on.

60 PSI is all that is needed for most applications. This is also why you have to be cautious when going to your local parts store and ordering an oil pump for a Pontiac - you may get the 40 PSI pump when you wanted the 60 PSI pump.


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## 1968GTOMAN (Aug 3, 2020)

Wow! This is anazing and very important.
Thank you for going out of your way to explain these details. I really appreciate it. Mine is a 1970 GTO engine, not Ramair. This is valuable to know these things!


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## pontrc (Mar 18, 2020)

PontiacJim said:


> You are correct. The AMA specifications show that the pump pressure was upped in 1965 for the GTO and other Hi-Po engines to 45-50 PSI @ 2,600 RPM's. The standard Tempest/Lemans/Full sized cars still used the 40 PSI pump - and the economy engine option in the GTO.
> 
> It is not until 1967 that the 55-60 PSI pump @ 2,600 RPM's is seen in the AMA specifications. The RA IV used the 60 PSI pump. Of note is that the AMA specs for oil list the Single Viscosity oil for above +32 degrees for the RAIV as 30W, as opposed to 20W for the non-RAIV, with the acceptable alternate viscosity for both the GTO/RAIV as 10w-30, and 10W-40 as an alternative only with the RAIV option.
> 
> ...


Nice work Jim


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## 1968GTOMAN (Aug 3, 2020)

Jim. Is it maybe possible that i have the 30 to 40psi oil pump in my 1970 GTO 4 barrel equipped engine? Maybe thats part of what is happening.
But update! The auto shop where the car is, i spoke to them today and they said one cylinder isnt firing, so they are doing a compression test and will let me know the results tomorrow the said.
Not sure if i should celebrate that at least they found something? 
Thank you!


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## Lemans guy (Oct 14, 2014)

I am hoping it is a bad plug or plug wire!...could also be a head gasket leak, coolant in the cylinder or any number of valve train issues, lifter, broke rocker arm, broke spring, burnt valve.... but more investigation needed..


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## Mine'sa66 (Oct 30, 2019)

1968GTOMAN said:


> Jim. Is it maybe possible that i have the 30 to 40psi oil pump in my 1970 GTO 4 barrel equipped engine? Maybe thats part of what is happening.
> But update! The auto shop where the car is, i spoke to them today and they said one cylinder isnt firing, so they are doing a compression test and will let me know the results tomorrow the said.
> Not sure if i should celebrate that at least they found something?
> Thank you!


This might help explain your low oil pressure at idle. Missing one cylinder is going to make it idle just above stall, which isn't going to make much oil pressure. You might have already pumped a lot of gas into your oil with that misfire lowering the viscosity by a lot.
Get your misfire straightened out, change the oil/filter, then see where you're at.


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## 1968GTOMAN (Aug 3, 2020)

Thank you!


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## 1968GTOMAN (Aug 3, 2020)

Havent heard from the shop, was hoping to today, it may be more than just misfire though?
I put new spark plugs in, wires looked new.


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## RMTZ67 (Mar 12, 2011)

As far as the ticking is concerned...After rebuilding my engine I also had a ticking. turned out to be exhaust leak in the intake. Almost sounded like a lifter. Used the ol hose to the ear trick to find it.


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## Mine'sa66 (Oct 30, 2019)

1968GTOMAN said:


> Havent heard from the shop, was hoping to today, it may be more than just misfire though?
> I put new spark plugs in, wires looked new.


A noise and a dead hole do not generally indicate good news  That being said, the permutations are nearly endless, with cheap and easy still being a possibility. All you can do is wait for the diagnosis.
We're all waiting with you, so post it up as soon as you hear!


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## 1968GTOMAN (Aug 3, 2020)

Thanks for staying with me!
The support is comforting as well as very educational!


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## pontrc (Mar 18, 2020)

She will get straight, Pontiac 400 is a tough ole gal 👍


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## 1968GTOMAN (Aug 3, 2020)

Yeah lol, and taking your 60s GTO to a shop is like taking your dog to a vet. You want your dog back lol.
Or at least updates.
If I had somebody's $30k car, id feel somewhat compelled to keep in touch with customers about their cars but companies around here in Fredericksburg Va, only a few of them work on old cars, and they dont have to worry about competition it seems. 

Yeah i hope they can provide me answers soon. Admittedly, i'd rather wait and get 
accurate diagnostics than get shoved out the door quickly and no fix.


Thanks!
Bill


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## Jared (Apr 19, 2013)

Good luck my friend. I hate to hear someone have this sort of bad experience early on. Hopefully this doesn't sour you on your GTO. You are doing the right thing getting this straightened out rather than driving it and hoping for the best. The problems only get worst once something big breaks (ask me how I know). You have come to the right place for advice. There are several guys on here who are extremely knowledgeable and willing to share what they know with novices like us.


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## 1968GTOMAN (Aug 3, 2020)

Yeah, glad ive found you guys!
Im sure the repair shop will properly diagnose the issue , but its a waiting game.
Will be 2 weeks wed


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## 1968GTOMAN (Aug 3, 2020)

Tomorrow will be 2 weeks that the car has been in this Fredericksburg Classic Car Center. It wasnt my plan to have the car sitting somewhere for 2 weeks with no answers.
They dont call to update me, theyre nice in person and on the phone but I have no idea if they are even working on it.
Im prepared to spend the money to fix or rebuild, whatever it takes...but Im losing my patience.
A simple phonecall from them would quiet my mind but they dont call.
Im having a party here at my house on Aug 22 and i need my car here for that.
Im an interesting guy, with an interesting house and an interesting car!
People who come need to see that lol, but seriously I need my car back.
Im afraid if i call them its going to irritate them, but theyre irritating me by not being in touch about whats taking place.
Im also afraid that if i tell then i want to pick up the car theyll say, "Oh, but we have the heads off the engine."
Itd be nice to know!

I dont know, i have such bad luck with mechanics. I went through hell with my 73 Charger in this town. Hoping with GTO to have a fresh start. Actually wasn't expecting to need a mechanic after just buying this car.

Bill


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## Old Man Taylor (May 9, 2011)

Anytime my car is in a shop anywhere, I check on it constantly - in person. I don't hassle them, I just want them to know that I am paying attention.


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## 1968GTOMAN (Aug 3, 2020)

Good point, i want to, its obviously bothering me, ....when i called them last thursday i just automatically started appologizing to the guy for bothering them.
I think it should have been him saying, "Oh yeah, sorry we havent called you "
He said tomorrow he shoukd know something. That was 5 days ago.
My friend said the diagnostics take time, But I would think that the diagnosis part would take less time than the actual repair.


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## Lemans guy (Oct 14, 2014)

Definitely go by and check your car out, be nice look at it you can tell a lot about what is being done by that, lift up the hood no matter where it is, say you want to look at something, if you don’t want to be too direct, but either style works, just make it your style, which sounds easygoing but you want to know....

and hey you are a car guy, from what you have talked about here you more about old classics than the average bear, you don’t have to be Rocky the guy who hand built a thousand hot rods....

go by check it out, talk person to person, tell him when you need it so please get me a diagnosis. He may be close but their are other shops, legitimate ones who can help you somewhere in Virginia

go to it good luck, you will have more info when you return.....


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## 67ventwindow (Mar 3, 2020)

I hate being at the mercy of some one with a car or working on my home.I have no idea what this shop s like that you took it to. I took my Chevelle to be painted in 1990. It was a one man shop I knew that when I dropped it off. But still as time went on the more backed up he got. I checked in once a week. After a while I started helping him out sweeping the paint booth, sanding cars what ever I could to get my car back. I ended up talking with him for hours. I paid 1500 for the paint job. It was worth 3000. I would go see the progress in person. It might give you more insight on whats going on. If you are planning on using the shop for other things. Building a relationship with them will only help.


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## Longs (Jul 21, 2013)

Now you don't have access to the car but my '67 400 makes a rattling noise at idle, I thought it might be lifters or a problem with the distributor, I eventually discovered that it was the vacuum distributor advance rod rattling, if I pick up on it under the advance mechanism the rattling stops. Just something to check, it took me a while to find it.


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## 1968GTOMAN (Aug 3, 2020)

Thats a good thing to check, ive googled and even began suspecting something could be going on with distributor rod.
But i never thought to pull up on the vaccume advance.
I will raise that possibility with them.
Today i called the shop, they said that two cylinders had slightly low pressure but they didnt act like it was any relation to the noise, . He said today his mechanic was focusing on the header exhaust leak, i dont think its that. I know they can make weird noises, but not metal clanking noise.


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## RMTZ67 (Mar 12, 2011)

I don't have much patience when someone has my car. But like others have said you tend to be at their mercy somewhat. I would stop by look at it, ask for all the compression numbers.....if they did not write them down,well maybe its time to pay the bill for doing nothing and get it out of there. if they did you know they at least looked into it then you can decide your next move. squeaky wheel gets the grease. Good luck.


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## 1968GTOMAN (Aug 3, 2020)

The problem is, the place is like a corporate headquarters. When you pull up, theres nobody around. You have to go in the front and your car is way inside in the back somewhere. So you cant just pull up and see someone working on cars.
What really is bothering, after just 2 weeks of it being there, is there is no phonecalls to update you.
Its a very expensive car, its not theirs, it's mine, and they should show some degree of accountability to not just the car, but the customer.
Yes. Im getting impatient, only because, theyve told me twice they eoukd call me and didnt.
That a red flag to me.
The customer shouldnt have to call you. You should call them.


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## Old Man Taylor (May 9, 2011)

You're going to have to walk in.


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## 1968GTOMAN (Aug 3, 2020)

On the phone he said, "I dont have details in front of me about what the mechanic found so far, he's at lunch, but after he comes comes back, ill get with him and call you."
I said, "So your definitely going to call me today??"
He said "Yes."
Well, he didnt.

Going in there might be kind of rude though. Personally, I cant stand it when people show up unnnanounced. With communication tools, ie phone, email, no excuse for just barging in on people.
Of course I dont have people's property either.

Its only been 2 weeks, id hate to go in there and be embarrassed to find out that they did a whole bunch of stuff and I feel foolish and mistrusting.
But yeah, if they did any compression test, shouldnt the car owner be informed ofbits results like RMTZ67 said?
Youre right that I need to see with my own eyes, but if show up, and they just say, "We havent had much time to work on it because we've been trying to finish up some other projects," id feel like an impatient jerk.
Hmmm.


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## pontrc (Mar 18, 2020)

Bill gooooo down their! Think about your goat needs your help she needs you ! This is the reason why I do everything in my power to do it myself!


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## 1968GTOMAN (Aug 3, 2020)

I do feel that 2 weeks is milestone of sorts. That timeframe should get a diagnosis, youd think 
This place, as I mentioned, its kind of a boutique for classic cars. They store them, they repair them, they sell them, they run car shows. When they took the car in the guy said, we have a waiting list but since you happen to be calling right at this moment that our mechanics are going to be finishing up and will need work we can take your car in later this week."
And keeping in mind, there arent many places that work on 60s cars in Fredericksburg Va. If I burn this bridge, which Im probably going to have to do, it kinda might affect something in the future, who knows what that could be?
You know how car guys all run in the same circles, they all know or know of eachother.


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## Jared (Apr 19, 2013)

I realize this won't help you right now, but once things get back to normal, go to some cruise ins or cars and coffee events in your area and talk to other owners. You may need to find a smaller shop close to you that works on old cars. There are probably more out there than you think. Another option is talk to the guy who works on your daily driver. Even if it's at a dealership, he may know a guy who does it. These bigger boutique places usually bring bigger boutique prices and longer waits


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## 1968GTOMAN (Aug 3, 2020)

Yes, you make a great point!
The "Boutique" place called me just now!
They said that the exhaust at the header was causing the noise, he said that they had to weld the header to flatten the seal. He added that the engine was running hot, like 218°. I never experienced it overheating but they are going to flush the radiator and put a 160 tstat in it.
But otherwise they said theres no more noise.
Im going to go ahead and have them remove the 750 edelbrock carb and the dual plane intake and put my holley 750 and single plane manifold on. I had just bought those. Theyre in the trunk.


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## Old Man Taylor (May 9, 2011)

It's amazing that a header leak will sound like a ticking noise, but I've had several that did that.


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## 1968GTOMAN (Aug 3, 2020)

Im still doubting it.


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## 1968GTOMAN (Aug 3, 2020)

This brings uo new questions.
Im running HEI.
The vacuum advance has nothing hooked up. Theyre saying the engine is running hot.
Will the vacuum advance help bring the temp down?
I wonder why its not hooked up?


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## PontiacJim (Dec 29, 2012)

1968GTOMAN said:


> This brings uo new questions.
> Im running HEI.
> The vacuum advance has nothing hooked up. Theyre saying the engine is running hot.
> Will the vacuum advance help bring the temp down?
> I wonder why its not hooked up?


Yes.

The single plane intake will be a mistake.

Can't wait to hear what the bill runs you - it's going to be a doozy.


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## Mine'sa66 (Oct 30, 2019)

I run a high volume shop. There's


1968GTOMAN said:


> Yes, you make a great point!
> The "Boutique" place called me just now!
> They said that the exhaust at the header was causing the noise, he said that they had to weld the header to flatten the seal. He added that the engine was running hot, like 218°. I never experienced it overheating but they are going to flush the radiator and put a 160 tstat in it.
> But otherwise they said theres no more noise.
> Im going to go ahead and have them remove the 750 edelbrock carb and the dual plane intake and put my holley 750 and single plane manifold on. I had just bought those. Theyre in the trunk.


So what about the dead hole? They said you had 1 cylinder not firing. What was the diagnosis there?


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## 1968GTOMAN (Aug 3, 2020)

He said $400 to put an intake and carb on. Thats not bad, but i dont know where the cost is yet for what theyve done.


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## 1968GTOMAN (Aug 3, 2020)

Yeah! I wondered that too but they said it wasnt a dead cylinder after all, just a hair lower than normal compression, said its nothing to worry about.


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## 1968GTOMAN (Aug 3, 2020)

"The single plane intake will be a mistake."
How come?
A mechanic who races says it will increase my power band, give more hp and it will be the best choice for me. Im looking for primarily street use, but want to dominate if I decide to take it to the track.
Im not really into drag racing, , i do want off the line power, but if i went to a track, i would much rather do high speed road course stuff.
He said its a myth that street cars wont benefit.
Ive been hearing both sides of the single plane vs dual plane opinions on google and other places. Im just trying to make the most informed decision.
I value and appreciate your opinions.
I need all the help I can get!
Thanks!
Bill


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## Mine'sa66 (Oct 30, 2019)

1968GTOMAN said:


> "The single plane intake will be a mistake."
> How come?
> A mechanic who races says it will increase my power band, give more hp and it will be the best choice for me. Im looking for primarily street use, but want to dominate if I decide to take it to the track.
> Im not really into drag racing, , i do want off the line power, but if i went to a track, i would much rather do high speed road course stuff.
> ...


There's no perfect solution. If there were, we'd all have the same one. Speaking in generalities. A single plane manifold will produce higher peak horsepower numbers. But, that's at very high RPM and is giving up low end HP and torque. A dual plane manifold is a compromise. Still performing at high RPM, but not sacrificing low RPM. Then you take it specifically to Pontiac engines, which are known for low end torque and now you're using something made for high RPMs on an engine that specializes in low end power. The folks here that build a lot of Pontiac engines will probably chime in with some more specific data.


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## 1968GTOMAN (Aug 3, 2020)

Thank you for this information about single and dual plane intakes! I need all i can get.
I guess i can just put it on there and see what happens and report back. This mechanic friend that races and has a busy repair shop who recommended I install a single plane, told me that i wont notice any loss in bottom end but will feel the improvement in upper rpm power.
Hes also recomending aluminum heads.
And my cam is an upgrade from stock, we just dont know yet what it is.
Im thinking if we change the intake, then we can find out what cam is there? And then make the next plan to do that.
I just spoke with my mechanic friend again and he assures me that like you said, these engines a low torque motors, so after around 3000rpms youre already at peak power.
And the single plane will provide power in the higher rpms where as the dual plane has already reached its limit.
He also mentioned that at drag strips youll never see a dual plane intake. So i guess we're taking the plunge with single plane!
Thanks!!
Bill


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## Old Man Taylor (May 9, 2011)

You may not be able to take your engine to a high enough RPM to take advantage of a single plane manifold. I still have a factory tri-power on my '64 GTO. "Back in the old days" (mid-70's) I ran 12.20 at 114 with a tri-power on top of a 400. You have to be careful with a lot of mechanics. If they're not familiar with Pontiac's they will build it like a Chevy. That won't work. Unless you really hop up the engine you want to stay with a dual plane manifold and a dual pattern camshaft. Also make them keep a 30 degree valve job on the heads. Chevy's like 45 degrees. My first rebuild on my 389 was like a Chevy. When I race it the performance was actually worse than the bone stock engine. B/T/W, I was shifting at 6000 when I ran 12.20. Admittedly my setup was optimized for the track, but the principles are the same.


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## Mine'sa66 (Oct 30, 2019)

1968GTOMAN said:


> I just spoke with my mechanic friend again and he assures me that like you said, these engines a low torque motors, so after around 3000rpms youre already at peak power
> He also mentioned that at drag strips youll never see a dual plane intake. So i guess we're taking the plunge with single plane!
> Thanks!!
> Bill


Yes, peak power at low RPM where a single plane is at a disadvantage.
Never is a big word, but yes at the strip, you'll see mostly single plane manifolds, and cars with slicks and ridiculous gears to create high RPM situations. There's a whole lot of stuff you see at the strip that you won't see on the street which is why you need to build your engine for where it's going to live.
Also, removing your intake isn't getting you any closer to seeing your camshaft.
Decisions, decisions


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## 1968GTOMAN (Aug 3, 2020)

Thanks, roger that!
Yeah, i dont want to neuter my engine by putting the wrong intake. Good thing though, it can always be changed back. 
The mechanic friend said because the pontiac engine runs at auch a low rpm it wont me a noticeable lag in power off linw but will benefit me as i reach past 3000 rpm.
Old man taylor eliquently said i wont ever reach those rpms to see the benefit
Im just confused. I trust everybody, and this is the place i feel im getting the best advice, I guess find out the hard way what happens after I switch it to single plane.
Worst comes to worse, no harm to engine, just a waisted gasket and some antifreeze?


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## Mine'sa66 (Oct 30, 2019)

1968GTOMAN said:


> Thanks, roger that!
> Yeah, i dont want to neuter my engine by putting the wrong intake. Good thing though, it can always be changed back.
> The mechanic friend said because the pontiac engine runs at auch a low rpm it wont me a noticeable lag in power off linw but will benefit me as i reach past 3000 rpm.
> Old man taylor eliquently said i wont ever reach those rpms to see the benefit
> ...


In all honesty, you'll probably not notice the difference. If you took it to the track and made some hits with the stock manifold, then switched and made a few more, there's probably a difference to the timer and the mph, but likely not a heck of a lot. You're definitely not going to neuter your engine either way. So no, just time, gaskets and coolant.
For the sake of conversation, I'd estimate most single planes are not at an advantage over most duals until closer to 5k RPM


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## 1968GTOMAN (Aug 3, 2020)

Yeah in my 73 charger with 440, (i sold), if i hit 4000rpms i was already around 70 mph.
So maybe, yeah, for street might not be a advantage. But i would enjoy some real power.


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## integrity6987 (May 10, 2017)

When you get it back and are comfortable with everything (specific "quirks" of your car) and the opportunity presents to do a stoplight pull to 60mph against a new gen Camero and you don't beat him. Switch back.😈


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## Old Man Taylor (May 9, 2011)

If you want real power you have to build the engine for it. It won't come from just a carburetor and manifold.


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## 1968GTOMAN (Aug 3, 2020)

No argument there! Maybe the only difference will be that its out of the trunk and on the engine. Its got a 750 edelbrock carb on there now that nobody seems to appreciate


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## PontiacJim (Dec 29, 2012)

I say this with no offense to you, but in reading into this post I am going to say that you have no mechanical experience and rely on others who do, and you have never owned a Pontiac.

So my suggestion is to first purchase a few books with regards to building Pontiac engines for bigger horsepower and torque so you have a good handle on what it takes and you know that your mechanic shop is installing parts that match and achieve your goals rather than wind up throwing good money onto bad and be disappointed. This is your ride and don't trust anyone to tell you how to change it or build it until you yourself understand what is being done.

We have a good listing of reading materials that cover a number of subjects to include engines:
Books, Pontiac Reading 

If your mechanic is suggesting aluminum heads, then I suggest considering a complete engine build and match all your parts that will work with aluminum heads.

You can install any intake you want, *but the key is to match parts*. I can't say it any better than Cliff Ruggles who is well known in the Pontiac racing community and puts his money where his mouth is.

"To date I've tested just about every intake that will fit under the hood of my Ventura (455CI), and a couple others on the dyno, back to back against our iron intake. The iron intake out ran all of them at the track, but only by a small margin. The intake that ran closest to the iron intake was a Tomohawk with a 1" spacer. It gave up nearly a tenth in 60' times, but ran only .02 seconds slower and over nearly 2mph faster than the iron intake with no spacer.

_So much for shifting power to a higher rpm for improved track performance. With good traction, an intake that makes the broadest power and torque is tough to outrun by one that gives up starting line and some mid-range power complemented by a strong top end charge._

We have heard for years how good some of the single plane intakes are. Recently we dyno'd a fresh 455 engine using 670 heads and a pretty hefty 248/256/108 hydraulic cam. We started testing with a Torker I intake, but the engine simply didn't like it, power numbers were off at all levels. We installed my iron intake, and immediately made over 50 more hp on the next pull. Does this mean the Torker one is a turd, not at all, the combination of parts simply didn't like it.

I think the single plane intakes have their place. On some really heavy hitting engines, we've made almost equal power with Torker II's and Tomohawk's outfitted with 1" spacers as Victor/Dominators.

FWIW, if you are moving around a heavy car with conservative gearing/converter, it's going to be hard to outrun an RPM or iron intake with a single plane intake. The last time we had my engine on the dyno, we tested a Torker II on it with a 1" spacer and HP950 carburetor. It made 2 more peak HP than our iron intake/Q-jet, but was WAY down on average power and gave up a lot of power in the lower rpm range. The only intake I've every tested that showed more power than the iron intake, that's total power, was the RPM. We've been running one this season, but have only been out 3 times, and haven't had an opportunity to back to back test it against the iron intake.

Last season we tested lots of intakes at the track, and when the smoke cleared the quickest run was made with the iron intake and no spacer, 11.64 @ 115.39mph. This was in near perfect weather, as the car would typically run 11.70's to 11.90 in hot/humid weather. This season we've went 11.50's at over 117mph with the rpm intake and new Hydraulic Roller cam, but haven't ran in good air yet. It is unlikely we'll do any more intake testing, at least not this season, I doubt if we'll even run the car again.

I would add that we attempted to test the standard Performer intake last season, but aborted testing, my engine would not run correctly with it in place. It acted like a restrictor plate, surging, pinging and out of power by about 4500rpm's. They are probably OK to about 450hp, but not well suited for our 455 application making over 500hp......Cliff "


You didn't state what intake you have, just single plane. Runner size is important. Smaller provides more port velocity, larger will slow it down - especially at the lower RPM's. Depending on the cam, this too can effect port velocity. Assume the Holley 750 is vacuum secondaries? It'll most likely need to be dialed in for your application. I am not a Holley guy, so can't provide any comments on a Holley.

So it is your car and you can try whatever you care to go with. The single plane/750 may be perfect for what you are looking to get out of the car. The single plane typically moves torque and useable HP up the RPM scale and can make the bottom RPM's a little "soggy" and if you have an engine you feel comfortable spinning 6,000 RPM's to take advantage of it, then it may be a good choice. How much low end might you lose, it may not be that noticeable per say unless you had track time to compare one combo against another. But, for street/daily use, the strong bottom end torque & HP of a dual plane is king.

When you get the car back, we all want an honest evaluation of your set-up and how you like it as compared with the dual plane and Edelbrock 750.


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## 1968GTOMAN (Aug 3, 2020)

Ill let you know for sure how it performs.
The way it is now is that its sprightly and can spin some tires, but flooring the gas pedal isnt very exciting, doesnt throw your head back.


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## 1968GTOMAN (Aug 3, 2020)

I do rely on mechanics who have umpteen years of knowledge. If they give me the wrong advice, yes its very costly, in time, money, materials and inconvenience.
By trade, Im a master gasfitter, work on gas heating products, particularly gas fireplaces. So im mechanical, do alot of things myself but i leave engine building to the experts.
I do things that are amazing but i dont know what im talking about when it comes to the proper camshaft, what stall converter i need, what lifters go with what springs. That goes way over my head. I just never focused on it. Its like some people are day traders and some people have no idea how to buy a share of stock. I have no stocks, i dont know how to get started with that. 
I had a pontiac Catalina when I was 17, loved that car! GM are my favorite cars. The 67 firebird is in my top 3 favorite along with the 68 GTO and late 60s -70s Corvette.


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## PontiacJim (Dec 29, 2012)

Well, if you can afford the gas, a rear gear change can do wonders for acceleration and you don't have to invest as much as you would into the engine to get the same results. So don't rule out gearing, both trans & rear.


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## 1968GTOMAN (Aug 3, 2020)

Yes sir! And luckilly the rear it has is the 12 bolt. 
Thats good, and auto transmission is supposedly freshly rebuilt. It has the his or her shifter. Nice setup. But yeah, again gears are over my head. I remember how hard it was just to find the right speedometer gear for my charger lol had to measure the tires, it still came out wrong. The GTO speedometer is off by 10mph. So thats another head-scratcher.


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## Mine'sa66 (Oct 30, 2019)

1968GTOMAN said:


> I do rely on mechanics who have umpteen years of knowledge. If they give me the wrong advice, yes its very costly, in time, money, materials and inconvenience.
> By trade, Im a master gasfitter, work on gas heating products, particularly gas fireplaces. So im mechanical, do alot of things myself but i leave engine building to the experts.
> I do things that are amazing but i dont know what im talking about when it comes to the proper camshaft, what stall converter i need, what lifters go with what springs. That goes way over my head. I just never focused on it. Its like some people are day traders and some people have no idea how to buy a share of stock. I have no stocks, i dont know how to get started with that.
> I had a pontiac Catalina when I was 17, loved that car! GM are my favorite cars. The 67 firebird is in my top 3 favorite along with the 68 GTO and late 60s -70s Corvette.


I owned a 68 Firebird for 12 years. Until my 66 GTO, it was my favorite car and there's been a long list.
Jim is onto what so many overlook. Do you know what the rear gears are? You may have some real soft gears in there, which might be why you don't get that throw your head back feel. You have the carb and intake sitting around and it sounds like it's going to drive you nuts if you don't , so get it on there and report back how she goes. Then get under there and find out your rear gear ratio.


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## Mine'sa66 (Oct 30, 2019)

1968GTOMAN said:


> Yes sir! And luckilly the rear it has is the 12 bolt.
> Thats good, and auto transmission is supposedly freshly rebuilt. It has the his or her shifter. Nice setup. But yeah, again gears are over my head. I remember how hard it was just to find the right speedometer gear for my charger lol had to measure the tires, it still came out wrong. The GTO speedometer is off by 10mph. So thats another head-scratcher.


we were typeing at the same time. 12 bolt! Awesome for you. Shouldn't be too hard to figure out the ratio. Will tell a lot.


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## O52 (Jan 27, 2019)

The 67-72 iron intake is a copy of the Super Duty intake manifolds from the early 60s race cars. Thats why they work as well as any aftermarket manifold.


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## 1968GTOMAN (Aug 3, 2020)

Ive got the torqer 2, there werent any other choices for the 400. And thanks "Minesa66" i guess we got to let our kids make their own mistakes, lol meaning me lol. Yeah I do want to at least see what if it does, if anything, i'll learn something maybe. Theyre doung the coolant and the carb, might as well pop that on there. I'll be glad to admit if it made it and less epic or more enhanced.
Im not hiding any data. 
And the gears, i was going to look at that, you think that is more important than doing a cam job as a next step?
I want highway speeds so I have to be careful as you know, finding a balance.


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## 1968GTOMAN (Aug 3, 2020)

67 and 68 firebird is one of the most beautiful creations made by man.


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## Mine'sa66 (Oct 30, 2019)

1968GTOMAN said:


> Ive got the torqer 2, there werent any other choices for the 400. And thanks "Minesa66" i guess we got to let our kids make their own mistakes, lol meaning me lol. Yeah I do want to at least see what if it does, if anything, i'll learn something maybe. Theyre doung the coolant and the carb, might as well pop that on there. I'll be glad to admit if it made it and less epic or more enhanced.
> Im not hiding any data.
> And the gears, i was going to look at that, you think that is more important than doing a cam job as a next step?
> I want highway speeds so I have to be careful as you know, finding a balance.


Yes, much more important. There's no point in setting up your engine without knowing what's there. Got real tall gears, you're going to need low RPM torque to turn them. Real low gears means things are going to spin up quickly and you'll be in a higher RPM range more often. The whole package works as one unit. Got to nail down as many variables as you can before making the hard decisions.


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## pontrc (Mar 18, 2020)

Check out the yellow firebird on Once apon a time in Hollywood near the end of the movie👍


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## pontrc (Mar 18, 2020)

Also Bill after the engine issues settle you could install a 200 4r in it to help with the gear ratios


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## 1968GTOMAN (Aug 3, 2020)

Hi thanks!
Im researching that thanks to your recommendation! I will learn.

So to everybody here who has generously been so interested in my 68 GTOs problem of the mysterious metalic clicking noise, and about the subsequent issues going forward, single plane manifold, etc..your advice has been very valued by me. I want you to know im honored to have your ear as well as your help!
I certainly will want to ask more questions so I hope I havent used up all my genie wishes.
Anyway, tomorrow, possibly or Friday, the car will be coming home from the classic car "Boutique" place.
They claim they have fixed the noise, as ive mentioned, by somehow welding/sealing a header leak, flattening out the header seal area.
Thats excellent, to not have to rebuild this year.
And to have the fall to enjoy showing off the car.
They went ahead and put the single plane torque II manifold on, and my Holley 750 double pumper. 
Im going to report as mentioned the results of that idea.
Several of you have expressed a valid point that if you want power you have to build it from the ground up and not just put things on top and expect it to make a big difference.
There is no doubt that that is true.

A racing mechanic who have been relying on for some advice has made good points as well that you need air/fuel to get energy for spark and power. He explains that a dual plane intake will route the air through passageways, but a single plane will deliver the air immediately, no tunnels to travel through.
He also explained that the 400 Pontiac engine being a low torque engine already has the built in low torque power therefore it's not going to lose that with a single plane manifold. He just explains that at higher RPMs the engine will gain power.
Lets see, and if it works it works, if not, it wont, im open to find out, and its already done, so lets see.
Also this friend who is a mechanic has a dyno so we will be taking the car there and tuning it to the best possible timing he says 
Im looking so forward to report back to you guys in the next day or two the results of the single plane, the dyno is a few weeks away..
Thanks for staying with me on this!!
Bill


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## 1968GTOMAN (Aug 3, 2020)

So i got the car back.
They installed the Holley 750 and the single plane manifold.
They got rid of a large portion of the engine clicking on the drivers side!, VERY HAPPY ABOUT THAT!!
But still noticeable is some engine clicking noise on the passenger side.

On my way home from the shop, the car stalled a couple times, had to pull over and restart it.
Theres a dead spot in the acceleration and it sputters out.

Now, as far as single plane vs dual plane question, i have to say that over 3000 rpms it does seem to have more power now. Before I could floor the accelerator, and not be going too fast right away but now I cant floor the accelerator at all because its too fast, too quick. Not throwing my head back though.

It doesnt appear to have lost any low end torque. Only appears to have opened up the higher end.
So, btw, I hooked up my tach, it doesnt dim, just stays bright, but thats least of my concern now. I hate to, but i guess i need to take it back to the boutique shop and have them see if they can figure out the sputtering/cutting off and the dead spot and see about the passenger side click noise.
(That click isnt really bothering me. Its so much better now that they fixed the big clicking sound as mentioned, but if it can be solved, it should be)


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## Jetzster (Jan 18, 2020)

So maybe another exhaust issue on the passenger side of engine and a carb dead spot issueRemains?how bad was the $$ hit,they did Not finish everything that was still wrong...


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## 1968GTOMAN (Aug 3, 2020)

Hey, how are ya? yeah, they originally were charging $700 to fix the driver side header leak, then they put in 160° tstat 
flushed radiator, which they said would put price to $1000.
Then...
Installed (my supplied) manifold
Installed (my supplied)new Carb
Changed oil
Then they started messing with rear brakes
Turned drums replaced rear pads and cylinders
Whole thing $1980.
Theres an update; I called them yesterday, they agreed to re-see the car. Im bringing it in today. Hopefully they dont charge me anything or much. 

With the single plane and the Holley, i have to say the car seems so much lighter now at take off. Its got power. But when im going in 2000rpms range i feel like im in a headwind or feels like still in 2nd gear, but thats where the dead spot might be affecting things.
But over 3000, i can go. Have yet to push it over 4000 because ill get reckless driving, too fast.
There was a bunch of roaring engine sound in front and inside the car before, but now its all in the back since they tightened up the drivers header. Just a really nice car, ill let you know what they do next 
Thanks for your interest
Bill


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## Mine'sa66 (Oct 30, 2019)

Did they just bolt the carb on or did they spend some time tuning it? Rarely is it a great tune right out of the box.
You really cannot make any determination about what the intake is doing/not doing for you until the carb is dialed in.
Even then you'll never really be able to attribute what's giving you what as you changed two things at once.
But, it really is of little concern as if it runs the way you want, that's the endgame. Doesn't matter how you got there.
Glad to hear they're willing to keep at it. 2 grand is full price....
Let us know how it goes!


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## 1968GTOMAN (Aug 3, 2020)

Thanks! They probably made a few adjustments seeing that they broke down and had to tow my car back to their shop during the test drive.
I like your analysis that changing two things will never identify exact results from one or the other.
The Holley 750 DPump carb could provide noticeable change in power though? Even if the other Edelbrock 750 was functionng pretty well? I guess so?.
But yeah, i mentioned to them that maybe it needs a different size squirter? ..I was just spit balling...
And they said if it does they'd certainly diagnose that and order the right one(s).
So i hope they dont start focusing on fuel pump pressure, i just put that new mechanical pump in and i hate when they start focusing on that. Thats a rabbit hole i went through with my 440 engine in my 73 charger. Had 3 mechanicals then switched to electric.
Yes, i hope its all about the carb.
Thanks!
Ill let you know. 
Bill


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## Mine'sa66 (Oct 30, 2019)

1968GTOMAN said:


> Thanks! They probably made a few adjustments seeing that they broke down and had to tow my car back to their shop during the test drive.
> I like your analysis that changing two things will never identify exact results from one or the other.
> The Holley 750 DPump carb could provide noticeable change in power though? Even if the other Edelbrock 750 was functionng pretty well? I guess so?.
> But yeah, i mentioned to them that maybe it needs a different size squirter? ..I was just spit balling...
> ...


Fuel pump pressure isn't usually an overwhelming concern in a carb. The pump simply needs to keep the bowls supplied with fuel. You can have too much pressure and force the needles open or too little pressure/flow and starve the carb at high rpm, but it doesn't seem like that's going on here.
Yes, if your former carb was working well, simply changing to a new carb that's working well isn't likely to make you stand up and take notice, but the question is; was your former carb doing all it could? Sounds like that's an unknown. Yeah, a tow back on a test drive is good cause to go back at it gratis....


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## 1968GTOMAN (Aug 3, 2020)

Yeah, it doesnt seem to starve for fuel at high RPM like you said., Its more about when coasting through parking lots, slow streets, going up a slow hill the engine starts to sputter and i have to pump the gas pedal, sometimes it stays running, sometimes it just shuts off. But when i pull over it starts right back up.
And revving the engine, yeah obvious instantanious dead spot.


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## 1968GTOMAN (Aug 3, 2020)

Nothings worse than driving passed a bunch of admirers looking at your beautiful GTO, and it stalls lol.
Its like being on stage and hitting bad notes.


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## PontiacJim (Dec 29, 2012)

Hmmm. I guess no one caught it. A double pumper has mechanical secondaries. That, in combination with a single plane intake is only asking for trouble. A double pumper typically needs a high stall converter and good gearing to get the engine up in RPM's fast, and the lower velocity of the single plane at lower RPM's, well.................

A vacuum secondary style carb is what you want for the street.


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## 1968GTOMAN (Aug 3, 2020)

Even sitting in neutral and revving it? Thats where the dead spot is apparent.


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## pontrc (Mar 18, 2020)

I would keep it out of that shop


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## PontiacJim (Dec 29, 2012)

1968GTOMAN said:


> Even sitting in neutral and revving it? Thats where the dead spot is apparent.


Possibly. When the mechanical secondaries open and suck in air and the accelerator pump/squirters are not sized to compensate, it's going to bog in the same manner if your primaries didn't get a good shot of gas when you opened up the carb. You can even experience backfire from such a lean condition. So my guess this is happening in the transition stage from primary opening to the secondaries popping open. I am not a Holley guy at all, but I now not to use a double pumper with mechanical secondaries unless you have a real "hairy" engine or a high RPM engine with high stall converter/gearing. I believe the secondary opening speed might be adjustable and can be timed to open a tad bit later, but not 100% sure.


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## 1968GTOMAN (Aug 3, 2020)

PontiacJim said:


> Possibly. When the mechanical secondaries open and suck in air and the accelerator pump/squirters are not sized to compensate, it's going to bog in the same manner if your primaries didn't get a good shot of gas when you opened up the carb. You can even experience backfire from such a lean condition. So my guess this is happening in the transition stage from primary opening to the secondaries popping open. I am not a Holley guy at all, but I now not to use a double pumper with mechanical secondaries unless you have a real "hairy" engine or a high RPM engine with high stall converter/gearing. I believe the secondary opening speed might be adjustable and can be timed to open a tad bit later, but





PontiacJim said:


> Possibly. When the mechanical secondaries open and suck in air and the accelerator pump/squirters are not sized to compensate, it's going to bog in the same manner if your primaries didn't get a good shot of gas when you opened up the carb. You can even experience backfire from such a lean condition. So my guess this is happening in the transition stage from primary opening to the secondaries popping open. I am not a Holley guy at all, but I now not to use a double pumper with mechanical secondaries unless you have a real "hairy" engine or a high RPM engine with high stall converter/gearing. I believe the secondary opening speed might be adjustable and can be timed to open a tad bit later, but not 100% sure.


Wow. 
I guess i could buy a vaccuum secondary carb. I always have to learn the hard way. Damn.
This is why my 73 Charger had $30k in it and it wasnt even painted yet. This is pissing me off. I rightfully rely on mechanics who actually race at tracks to give me advice. I just dont see how this can keep going wrong.


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## pontrc (Mar 18, 2020)

Bill I would believe in people in this forum before this shop, and talk to people with cars in your area clubs, at shows they will help you out. But this shop definitely is not helping you


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## 1968GTOMAN (Aug 3, 2020)

PontiacJim said:


> Possibly. When the mechanical secondaries open and suck in air and the accelerator pump/squirters are not sized to compensate, it's going to bog in the same manner if your primaries didn't get a good shot of gas when you opened up the carb. You can even experience backfire from such a lean condition. So my guess this is happening in the transition stage from primary opening to the secondaries popping open. I am not a Holley guy at all, but I now not to use a double pumper with mechanical secondaries unless you have a real "hairy" engine or a high RPM engine with high stall converter/gearing. I believe the secondary opening speed might be adjustable and can be timed to open a tad bit later, but not 100% sure.


Okay!! So here's the deal. You are very correct! 
My mechanic friend, he races Honda Civics and is very knowledgeable about all aspects of cars and engines but for some unknown reason he missed the boat on this one.
You have opened my eyes very wide by explaining the differences between the mechanical secondary and the vacuume secondary. I also watched the short video which clearly states the difference.
So i just called Holley, which has great tech support, they echoed your assertion about the double pump carb as being WRONG for my street/strip car.
So i just putchased the dual feed 750 vacuume secondary carb. Then called the shop the car is in and told them "Stop the presses" on the carbeuretor tuning!
The guy there said "We've installed tons of carbs, we won't have any problem, we can make your double pumper work."

I said "How bout NO!!!!"

So they found a leak at the other header, theyre working on that instead and also fixing my gas gauge, while the carb is one day shipped to me.
Yeah, i learn the hard way. Even when I go to professionals they send me out looking for a "Left handed smoke shifter"
Thats what happened in Boyscouts. When we were at camp they played pranks telling us scouts to go get things that dont exist.


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## O52 (Jan 27, 2019)

Muffler bearings come to mind.


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## 1968GTOMAN (Aug 3, 2020)

O52 said:


> Muffler bearings come to mind.


When the boutique shop said "Starter shims" the other day i thought the same thing.


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## integrity6987 (May 10, 2017)

1968GTOMAN said:


> When the boutique shop said "Starter shims" the other day i thought the same thing.


At least those are real items.....but it is kinda a "measure twice cut once" Dudes on this forum know PONTIAC and how they were engineered to lead the pack back in the day. They are great high-torque engines and are a blast to drive and reliable if (as PJ and others have pointed out) all the pieces work together.


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## Lemans guy (Oct 14, 2014)

Yes PJ is right, I use a vacuum secondary QFT 780 CFM carb on my 461. Racers are very knowledgeable, but if you are not racing a lot of those things make operating a street car harder......I know you are trying for a street/strip car so you can work to that.....

but many things that racers do you do not want to do for a car tat spends lots of time on the street......


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## 1968GTOMAN (Aug 3, 2020)

Lemans guy said:


> Yes PJ is right, I use a vacuum secondary QFT 780 CFM carb on my 461. Racers are very knowledgeable, but if you are not racing a lot of those things make operating a street car harder......I know you are trying for a street/strip car so you can work to that.....
> 
> but many things that racers do you do not want to do for a car tat spends lots of time on the street......


Thank you! Yes I agree, ive been telepathing that to all the mechanics i have advising me but they for whatever reason dont know, i guess.


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## 1968GTOMAN (Aug 3, 2020)

I put the vacuum secondary carb on it and it was a big dud. Had to put the mechanical secondary carb back on.
Im using single plane manifold.


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