I posted this on LT1 tech without any luck:

What head gasket would one buy if he was interested in lowering his compression as much as possible?

I have a Felpro head gasket right now with 11.3:1 compression.

I figured going back to regular stock GM head gaskets would put me at 10.8:1 compression.

Is there a fatter aftermarket head gasket available to lower it a bit more?

I'm thinking about a turbo kit.

 

http://www.headgasket.com/whoweare.html

The place above makes custom head gaskets out of copper in any thickness you want. There are lots of places that will make a custom gasket. Your biggest problem is finding an LT1 compatible gasket. Fel-pro and others have .051 gaskets, but I don't think they are for the LT1.

I think SCE makes custom copper gaskets also.

http://www.scegaskets.com/

 

Dished pistons would be the preferable route.

 

Using a thicker head gasket (reducing quench) is an invite for detonation.
I'd follow the Doc's advice and use a dish piston to arrive at a target comp. ratio. I wouldn't worry about 11.3:1.

-Mindgame

 

The reason I want to lower the compression is because I want to run an 8psi turbo

What exactly is quench?