I'll be running the new 355 that with standard thickness head gaskets, and 64cc chambers will yield about 9.25-1 compression. I wanted it to be up around 10-1 but I was going to use my 57cc Vortecs.

So if I use the super thin gasket that compresses to .015 instead of .039 or .041 I won't be screwing up the efficiency of the heads and all that jazz right????

I figure the little bit more compression will yield a pony or two.

Edit: I think it's 9.25-1, but now that I'm thinking about it I believe it's 9.75-1.

 

Yes it's fine to use a thin gasket. It'll raise compression about 1/2 point.

 

well i never did the math but i think kfoley is a bit optomisstic in gaining a half point of compression with .024 less head gasket. also head gasket thickness isn't the way to make or remove compression, you may also want to consider quench when you make your gasket selection.

 

Well I was going by how much it raised compression on my 305. Yours would probably be a bit less.

 

I wouldent bother. I dont think a thin gasket is worth the potential problems. Yep I'll stick to my nitro seal gaskets and not worry about maybe 2hp.

 

2hp huh.....were not talking about a weenie motor here.

Even a quarter point of compression is worth at least some decent power.

This motor will put out 425 or more either way, but I want the most I can get. Half a point is a bit high, yes, probably a bit closer to .3-.35 of a point, which is good.

 

The stock GM gasket for Vortec heads is .028" thick. I don't know the part #. Too many numbers in my head as it is.

That maybe what you're looking for.

 

Here's the composition gasket.....
http://www.sdpc2000.com/cart.asp?act...id=576&pid=651

Here's the graphite.....
http://www.sdpc2000.com/cart.asp?act...id=576&pid=724

 

I've never had headgasket problems no matter what. Just make sure the surfaces are flat.