72 BB Intake Manifold Gaskets

[Anthony D.]

[Joe L.]

Re: 72 BB Intake Manifold Gaskets

Hi all,

I have my intake off and getting ready to reinstall with fresh gaskets.

From what I’ve read here, seems like 2 options, repro or nos.

The gaskets that came off the car were GM, but service replacements that have more gasket material across the center ports.

the originals had less material there.

My questions:
- any issues with nos due to age or sealing tech?
- any issues with the original configuration, ie less sealing surface than the later versions?
- anyone have experience with the quality of the repros?

Whichever way I go, I’m planning to skip the rubber end gaskets and use a good rtv. I appreciate originality but I also forgo it for additional quality or reliability.

Thanks in advance for any suggestions.

Anthony------


When you refer to "NOS", what is the part number of the "NOS" gasket set you are referring to? There are several gasket sets available from GM over the years that are not necessarily "NOS" for 1972.

[Anthony D.]

Re: 72 BB Intake Manifold Gaskets

Anthony------


When you refer to "NOS", what is the part number of the "NOS" gasket set you are referring to? There are several gasket sets available from GM over the years that are not necessarily "NOS" for 1972.

[Joe L.]

Re: 72 BB Intake Manifold Gaskets

good question. Don’t know the pn. Here’s a picture.

Anthony-----

This gasket set appears to me to be an original configuration gasket set as used for 1972 LS-5 with one exception. The exception is that the exhaust cross-over has a restrictor plate installed. Original LS-5 gaskets did not have the restrictor plate. Gaskets with restrictor plates were used on many truck big block applications. If you removed the restrictor plates, these gaskets should be correct for your application.

[Anthony D.]

IMG_2208.jpg

[Joe L.]

Re: 72 BB Intake Manifold Gaskets

Thanks. I had planned to do that so there’s no issue with the choke. This is what I took off the car. I’m gonna to use permatex right stuff or something similar for the walls.

[ATTACH=CONFIG]123499[/ATTACH]

Anthony------

Those are later GM replacement gaskets supercessive to the originals or aftermarket. I do not believe that style gasket was used as early as 1972. So, I would say that the manifold has been off before which is not unusual for a car more than 50 years old.

[Anthony D.]

[Mike M.]

Re: 72 BB Intake Manifold Gaskets

cut the tabs off the end seals and insert them in the drying right stuff, front and rear. mike

[Mark E.]

Re: 72 BB Intake Manifold Gaskets

Unless you plan to regularly drive it in freezing temperatures, consider leaving the cross over restrictions in place or blocking them completely. You may need to adjust the choke but it will run stronger and be less susceptible to percolating (a problem with modern fuels).

Also, wire open the heat riser or replace it with a spacer.

These two things will minimize carbon build up in the cross over passage and keep the intake cooler.

[Anthony D.]

Re: 72 BB Intake Manifold Gaskets

Great idea 👍

[Anthony D.]

Re: 72 BB Intake Manifold Gaskets

Thanks. Great tips!