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Finally got my "new" carb today.
A remanufactured (I guess) Rochester-Q
It came with the bottom gasket and the one on the left that seems to be made of some sort of bake-lite type material.
Can I use it or should I stick to the metal one?
thanks as always
Tk:seeya:
 

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What is it going on? The one on the right, is for the intakes that have a transfer groove cut in them (alot of early Chevy's had that). The one on the left is probably the one you need on a Pontiac. If you take a picture of the intake and post it here I could say for sure.
 

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The one on the right is a '67 only GTO base gasket, needed with the stock intake on '67 only. You need the metal block off plate that seals the heat passage from the carb, and it goes between the carb and the gasket. I got mine from NAPA, and they actually had it in stock. Looks like a metal carb gasket, but does not have the "groove" The black plate/gasket is for later models and not your car.
 

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gasket gets matched to the intake and the carb base. thin metal one also requires another gasket for sealing purposes, not just the metal one. best to look at the carb base to ensure the proper one is used. they are not universal.
 

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gasket gets matched to the intake and the carb base. thin metal one also requires another gasket for sealing purposes, not just the metal one. best to look at the carb base to ensure the proper one is used. they are not universal.
Are you saying there needs to be 3 gaskets total?
Never seen that....
 

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pontiac is correct. With the '67 intake (and carb, which is a one-year only deal) you install a gasket at the intake, install the plate, add a gasket between the plate and the carb. That's how mine is, and it's all original. The gaskets are pretty thin. If you have a '67 intake and a later model q-jet, I think the steel blockage plate is still needed to keep hot exhaust gasses from cooking the carb.....
 

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I was searching for the carb gasket sequence and came across this post. Is the one on the right the plate which is simply sandwiched between the two gaskets?
1 intake, 2 gasket, 3 metal plate, 4 gasket, 5 carb. I'm cofused, ames said I only need the two.
 

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pontiac is correct. With the '67 intake (and carb, which is a one-year only deal) you install a gasket at the intake, install the plate, add a gasket between the plate and the carb. That's how mine is, and it's all original. The gaskets are pretty thin. If you have a '67 intake and a later model q-jet, I think the steel blockage plate is still needed to keep hot exhaust gasses from cooking the carb.....
This is true plus the gasket with the slot needs to be installed correctly, or you'll have a vacuum leak. For the passage itself (on the intake manifold) you can plug the passage ports with 11/32" (I think) plugs. Measure to make sure, but it definitely keeps the heat down under the carb.

Chuck
 

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Chuck is correct. The steel plate that goes between the gaskets has no slot....it closes it off to keep the carb from baking. The manual calls for one plate and one gasket, I like to use a gasket on both sides of the plate, for better sealing and better heat insulation. So, two carb gaskets, with one plate in between.
 

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OK, I just want to confirm. From the picture posted by Topkat, I have just recieved from Ames the two gaskets on the right and the one metal one on the left. The metal will be simply sandwiched between the two gaskets and it seals the heat groove on the carb or manifold?????
 

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I know this is an old thread, but new to me and pertinent as I’m gathering the parts and information to replace a Holley carb/Edlebrock intake with a date correct Qjet/Pontiac intake on a 49 state 67 400/4spd. So the recommended gasket “stack up” is standard $10 gasket/$20 metal gasket/standard $10 gasket?

Does anyone recognize the “NOS GM/AC Delco Quadrajet Carburetor Heat Shield Insulator” in the attached picture?
 

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Thank you PontiacJim!

So in my “stack sandwich” the “NOS GM/AC Delco Quadrajet Carburetor Heat Shield Insulator” would serve as the “$20 metal gasket”? Is the GM/AC Delco Quadrajet Carburetor Heat Shield an extraneous item (with all the apparently excess metal around the sides) compared to what is commonly available (a “simple” carburetor size metal gasket)?

Do you know of any pictures of a 67 GTO with a “GM/AC Delco Quadrajet Carburetor Heat Shield Insulator” installed (non Ram Air)?
 

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Have never seen one used on a car or GTO in all the car shows I have attended over the years, but have seen them loose or in pictures as you have.

Chevy engines used a heat shield more like your typical carb gasket because the intake had an exhaust heat slot that went under the front of the carb - like the 1967 only Pontiac intake. This metal heat shield sealed off the slot in the intake and then the carb went on top. The larger heat shield such as you have would seem to be an extension of that design in that it kept additional heat off the carb when you shut the engine down - "heat rises and when the vehicle’s engine is turned off, the rising heat can easily penetrate the carburetor and cause the fuel in the float bowls to expand and eventually boil or percolate."

Doing a quick web search it seems the larger heat shield was offered by GM on their Chevy performance engines and the earliest date I found with a picture of one was 1969. So late 1960's and early 70's. Not sure when they discontinued their use on factory cars.

Read on one blog that the gasket goes between the plate and top of the intake manifold and the carb then sits on the plate. The aluminum is soft enough to create a seal between the base of the carb and the plate - but I personally would use a thin undercarb gasket myself just to ensure no issues in case their might be any slight warping anywhere.

Here is a discussion on it and photo of one at the bottom link if you click on it. https://cliffshighperformance.com/simplemachinesforum/index.php?topic=1015.0

This pic/description may be the same one from above and it says both gaskets are attached, which is what I would use anyway and more often not, two gaskets are mentioned. https://paceperformance.com/i-6250300-10147945-gm-quadrajet-carburetor-heat-shield-oem-chevelle-camaro-nova-z28-item-fits-all-qjet-carbs.html

It seems to me to be rather bulky and I don't know how effective it really is. I might opt for a phenolic spacer under the carb instead if you have the hood clearance - they come in 1/2" & 1" thickness. https://www.summitracing.com/search/part-type/carburetor-spacers/carburetor-spacer-material/phenolic-plastic?N=4294921304
 
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