Exhaust Manifold Gaskets - YES OR NO?

[89Suburban]

Let's see your votes! Your experiences. I plan on replacing my exhaust manifolds. Who here uses gaskets against the block or not?

Many of you may remember my heads replacement thread and I used the gaskets and a few here asked wtf I was doing that for lol. I never thought NOT to use them so I would like to get a sample here from the members what they do/did with theirs!

 

[skysurfer]

I thought you had to. But then again, I was surprised by a former co-worker engineer who rebuilt his Chevy Monza with such close tolerances he ran it without head gaskets.

 

[Stroked]

Yes, because I assumed you were suppose to.

I'm interested to find out what others thoughts are on this subject.

 

[MrMarty51]

Those surfaces are machines,so,no gasket is required,IF them surfaces are undamaged.
If I am instralling them exhaust manifolds and if the machined surfaces are damaged I dress up the surfaces using a sanding block and then I will use the gaskets,if it looks like there`ll be a problem if I do`nt.

 

[Jims86]

nope!

 

[Driver4r]

Yes, you need them. Who cares if the surfaces are machined or not. even flat surfaces against each other will seep exaust fumes out.

 

[Jims86]

Yes, you need them. Who cares if the surfaces are machined or not. even flat surfaces against each other will seep exaust fumes out.

GM didnt think so...you only need them with headers. and, you are wrong, a perfectly machined surfaces of both parts does not require a gasket...in fact, gaskets can cause exhaust manifold warpage.

 

[bucket]

GM didnt think so...you only need them with headers. and, you are wrong, a perfectly machined surfaces of both parts does not require a gasket...in fact, gaskets can cause exhaust manifold warpage.

Correct on all counts. GM didn't use them and I don't either.

 

[Driver4r]

GM didnt think so...you only need them with headers. and, you are wrong, a perfectly machined surfaces of both parts does not require a gasket...in fact, gaskets can cause exhaust manifold warpage.

Ive never seen an engine without them. I wasnt around when squares were new. But all the newer stuff has manifold gaskets. And ive seen ALL-ORIGINAL Chevelles/Impallas with the factory manifold gaskets.

 

[bucket]

Ive never seen an engine without them. I wasnt around when squares were new. But all the newer stuff has manifold gaskets. And ive seen ALL-ORIGINAL Chevelles/Impallas with the factory manifold gaskets.

The factory DID NOT use manifold gaskets until the LT1/Vortec years, and those were nice stainless or graphite gaskets, not the crappy paper gaskets that come with a gasket set.

 

[smurph20]

I always just go with if it was there when i tore it down then it goes back when i reassemble it.

 

[Driver4r]

ok, I WAS WRONG, and ill admit it. I was just told that they started using manilfold gaskets to try and stop manifold warpage.

 

[bucket]

ok, I WAS WRONG, and ill admit it. I was just told that they started using manilfold gaskets to try and stop manifold warpage.

It's alright to be wrong sometimes, everyone's allowed to be It's funny though, I never saw so many broken manifold bolts until GM started using gaskets.

 

[Jims86]

Ive never seen an engine without them. I wasnt around when squares were new. But all the newer stuff has manifold gaskets. And ive seen ALL-ORIGINAL Chevelles/Impallas with the factory manifold gaskets.

They didnt come from the factory with them. Great uncle was a part of GM development for a long time, told me if he ever caught me using gaskets on anything other than headers, he would go grab the Hidden white 85 454 SS and drag me from the bumper, old west style. said the same thing about silicon gasket shputz.
lots of the newer vehicles have them, because they are usually against aluminum heads.

 

[Jims86]

ok, I WAS WRONG, and ill admit it. I was just told that they started using manilfold gaskets to try and stop manifold warpage.

Actually made it worse...LOL.
The gaskets allow more movement than without with heating and cooling.