Exhaust gaskets

[Calvin C.]

This may be a goofy question, but I am assuming there is no exhaust manafold gasket used, correct? I am putting my 69 350/300 engine back to specs.

thanks

cal

[R N.]

Re: Exhaust gaskets

You are correct.

[Calvin C.]

Re: Exhaust gaskets

You are correct.

Why do you think everyone uses them? Maybe if your headers are warped, but the gaskets may cause warping. Even the shop shows on TV always use them on chevy small blocks, and tell you not to forget them. Do the big blocks use exhaust manifold gaskets?

thanks

cal

[Patrick H.]

Re: Exhaust gaskets

Why do you think everyone uses them? Maybe if your headers are warped, but the gaskets may cause warping. Even the shop shows on TV always use them on chevy small blocks, and tell you not to forget them. Do the big blocks use exhaust manifold gaskets?

thanks

cal

You always believe what you see on TV?

Me neither. Don't believe what I read on the internet either.

As I've posted previously at one time (pre-NCRS discussion board) I tried exhaust gaskets. After replacing them yearly (different companies, different styles) because they burned out I finally had my manifolds trued and installed them. Zero leaks since then.

[Joe L.]

Re: Exhaust gaskets

Why do you think everyone uses them? Maybe if your headers are warped, but the gaskets may cause warping. Even the shop shows on TV always use them on chevy small blocks, and tell you not to forget them. Do the big blocks use exhaust manifold gaskets?

thanks

cal

Calvin------


Exhaust manifold gaskets were never originally used on any Corvette or other Chevrolet V-8 engine except 80-82 Corvette with tubular-type manifolds. These were very expensive gaskets and nothing like the ordinary ones seen for cast iron manifolds.

The biggest reason why folks use the exhaust gaskets is because they are usually supplied with "valve grinding" gasket sets or complete engine rebuild gasket sets. So, mechanics or owners figure they are supposed to use them. I never have, though, and I've never had any leakage problems.

Actually, though, I like the idea of using exhaust gaskets for aluminum head engines with cast iron manifolds. For the most part, GM did not, but I like it. However, I would only use exhaust manifold gaskets that are of the MULTI-LAYER STEEL type. These were actually used on some MUCH later big block engines but never during the era when big blocks were installed in Corvettes.

[Richard G.]

Re: Exhaust gaskets

Once the aftermarket caskets have been installed it is usual to leave an impression in the manifold and the head. After they have been installed many times you will have to reinstall them to keep a seal. I would just confirm the head and manifold are flat and straight and install them just like GM did. The SBC had many issues but leaking exhaust manifolds was not one of them at least on the automobiles.
Rick