Early F.I. Intake Manifold Gaskets

[Stuart F.]

Can anyone tell me if GM or any aftermarket provider still makes the V8 Intake Manifold Gaskets that used to be specified for early F.I. engines. They featured a metal block off piece in the exhaust heat riser passages that was laminated or crimped into the gaskets. The metal piece had an oval hole in it (don't know why), and we used to use them on all our performance engines back in the day. They restricted the passages, still allowing some exhaust heat through. They gave you the best of both worlds, so to speak, for the northern climates.

I haven't seen these in years, but they sure would be a nice item to have for our old Vette in our warmer climates. I never could understand why Chevy even bothered to make them that way for the F.I. application which have no passages there in the lower manifold anyway.

Stu Fox

[Dan H.]

Re: Early F.I. Intake Manifold Gaskets

Stu, paragon sells them.
Dan

[Alan D.]

Re: Early F.I. Intake Manifold Gaskets

Stu, just FYI
I have two old sets of 3772384 (Gr. 3.270) intake gaskets for the FI. Neither have any blockage for heat riser. Know what you are talking about since I've had many a set which came with the metal blocking plates, none left. The over the counter Felpro sets have a small hole at the heat riser.

[Michael H.]

Re: Early F.I. Intake Manifold Gaskets

Stu, just FYI
I have two old sets of 3772384 (Gr. 3.270) intake gaskets for the FI. Neither have any blockage for heat riser. Know what you are talking about since I've had many a set which came with the metal blocking plates, none left. The over the counter Felpro sets have a small hole at the heat riser.

I think Alan is correct. The gaskets in the set specifically called out for engines with FI had only one small item that was different than a set for non FI engines. That would be the distributor mounting gasket. There were two instead of one and each had a small notch cutout for the distributor spacer locating pin.
The manifold to head gaskets were the same as those used on non FI engines.

Many aftermarket companies made intake gasket sets with the small metal block off plate.

[Clem Z.]

Re: Early F.I. Intake Manifold Gaskets

those SBC intake gaskets with the block off plates with holes in them were used on late model engines with carbs and they had something to do with the hot air auto choke operation that had a loop of SS tubing in the heat riser croosover in the intake. the only intake gasket with completely blocked heat riser crossovers were for the BBC

[Stuart F.]

Re: Early F.I. Intake Manifold Gaskets

Clem;

The gaskets I recall are ones I last used say in 1961 before I went into the service and put my hot rod days behind me. They were on my original 58 fuelie engine when I first changed it to dual quads, and I used them a number of times after that whenever I changed manifolds. I have not seen them since, and that's why I asked. There were no divorced chokes or unusual heat riser configurations back then that I can recall.

If I pull the manifold, I would want to have a set of block off gaskets or ones with the holes to reinstall it with. I would probably still test before hand with the shim stock to make sure it works ok.

Stu

[Clem Z.]

Re: Early F.I. Intake Manifold Gaskets

Clem;

The gaskets I recall are ones I last used say in 1961 before I went into the service and put my hot rod days behind me. They were on my original 58 fuelie engine when I first changed it to dual quads, and I used them a number of times after that whenever I changed manifolds. I have not seen them since, and that's why I asked. There were no divorced chokes or unusual heat riser configurations back then that I can recall.

If I pull the manifold, I would want to have a set of block off gaskets or ones with the holes to reinstall it with. I would probably still test before hand with the shim stock to make sure it works ok.

Stu

i have to admit i never saw GM sold SBC intake gasket with blocked off heat risers except the ones i posted about above. there were after market ones from most of the manufactures . the guys here with the old GM parts catalogs should be able to check.

[John N.]

Re: Early F.I. Intake Manifold Gaskets

I believe that Chev supplied block off plates in a envelope with some straight axle cars. Dave Bartish wrote a article on this in a early Restorer. I own the car GM tested them on. Engineering #6911, 56#1009.
Regards

[Michael H.]

Re: Early F.I. Intake Manifold Gaskets

i have to admit i never saw GM sold SBC intake gasket with blocked off heat risers except the ones i posted about above. there were after market ones from most of the manufactures . the guys here with the old GM parts catalogs should be able to check.

I agree Clem. I still have a few sets of the original 3772684 FI intake gaskets and the heat cross over is open.

[Stuart F.]

Re: Early F.I. Intake Manifold Gaskets

The block off plates I recall (w/holes) were of a "blued steel" material, not a silver or SS looking finish. Does that ring a bell with anyone?

Otherwise, I'm going to bed tonight to dream some more, I guess.

Thanks anyway.

Stu Fox

[John D.]

Re: Early F.I. Intake Manifold Gaskets

Stu, I thought you had a 63 carb car. Anyhow the guys already answered your question. The repro gasket sets are OK for a driver but not for judging. The camel hump is incorrect but can be massaged. The rubber ends are totally incorrect for judging as they lack the tab with the GM logo. None of the FI gaskets from 57 to 65 had he block off plaste as was already mentioned.
If you need the originals a friend of mine may have a set left-the later style anyhow.

Now I have a question about some repros I just got that are supposed to be correct for 57 up to 61??? Instead of the camel hump they are cut off flat with a stub sticking up. Meaning the repro guys took the camel hump ones and just cut off the top of the camel hump and made them straight across.
What's the scoop here on those gang??? Let me say this another way. So when did the camel hump start on the intake gaskets. And what was the configuration of the camel hump area before???
God I wish I knew how to take pics and post them.

[Gary C.]

Re: Early F.I. Intake Manifold Gaskets

John, go buy you a Canon Powershot. Don't need anything over 6 megapixel. Canon software is plug and play. Recall you have a new PC in the last year. Need a USB port on the front. After taking photos, plug the camera USB cable into the PC port and hit the download/transfer button when the page pops up and the Canon photo software puts the photos in the My Pictures directory. Then all you have to do is resize them to fit the TDB requirements. If you have XP go to this link http://www.microsoft.com/windowsxp/D...powertoys.mspx amd select "Imagine Resizer" downloand which is about the middle of the download selections. It's simple to use from "explorer" by right mouse button click on the "Start" button. Then read the TDB FAQ about posting photos. Good luck. Let us know how you make out. Most Canon Powershot cameras about $150 or less. Gary....

[William C.]

Re: Early F.I. Intake Manifold Gaskets

In the early days the camel hump was indeed a rectangular tab. I had an NOS set of those around here at one time (black and Gold packaging) Camel hump started in '62 or '63 as best I could tell tracking the part numbers a few years ago.

[Stuart F.]

Re: Early F.I. Intake Manifold Gaskets

John;

The reason I'm looking for early F.I. intake gaskets or ones w/block off plates for the heat risers is that I am still trying to deal with my severe percolation problem. My experiments have led me to determine the heat to the carb is causing the problem, and most of it is coming up through the intake manifold during shut down (heat soak) literally causing the fuel to boil. My latest test, with a laminated spacer under the carb, is going well. The difference in temperatures between the manifold and the carb body during the shut down shows a reduction of about 20 to 25 degrees using the spacer (was only 5 to 7 Degrees w/o). I have been taking I.R. temp readings and recording them every 10 minutes after shut down. On my last tests with the spacer, I did not have any fuel streaming from either the main nozzles in the venturi clusters or through the accelerator nozzles - with either test carb (3720SA or 3721SB).

Trust me, I would hate to pull that manifold for the first time ever in 45 years, but the situation has gotten intolerable. I can't live with the stink and the potential for hydraulic lock, etc. My show days are over, I just want to have fun with the car in my remaining years or until they outlaw it (may happen in the first term, don't ya think?).

Stu Fox

[Clem Z.]

Re: Early F.I. Intake Manifold Gaskets

John;

The reason I'm looking for early F.I. intake gaskets or ones w/block off plates for the heat risers is that I am still trying to deal with my severe percolation problem. My experiments have led me to determine the heat to the carb is causing the problem, and most of it is coming up through the intake manifold during shut down (heat soak) literally causing the fuel to boil. My latest test, with a laminated spacer under the carb, is going well. The difference in temperatures between the manifold and the carb body during the shut down shows a reduction of about 20 to 25 degrees using the spacer (was only 5 to 7 Degrees w/o). I have been taking I.R. temp readings and recording them every 10 minutes after shut down. On my last tests with the spacer, I did not have any fuel streaming from either the main nozzles in the venturi clusters or through the accelerator nozzles - with either test carb (3720SA or 3721SB).

Trust me, I would hate to pull that manifold for the first time ever in 45 years, but the situation has gotten intolerable. I can't live with the stink and the potential for hydraulic lock, etc. My show days are over, I just want to have fun with the car in my remaining years or until they outlaw it (may happen in the first term, don't ya think?).

Stu Fox

there is no need for the FI intake gaskets to have a crossover blockoff because the FI base plate that bolts to the block has no heat riser passage to block off..