forged ls2 9.1 cr.
setup was going in my camaro but ended up selling along with turbo kit. motor is now going in a 2004 gto but I havent found a forced induction system for a decent price, how can I raise the compression in the motor without swapping pistons. and by how much?

 

Mill the heads.

 

You can get some thinner head gaskets or mill the heads.

 

in addition to the above, you can deck the block.

 

First question to ask is will the motor stay N/A or do you plan to run boost/nitrous later on? If you plan to throw boost at it I would not mill the heads.

 

You can do all that, but I doubt you're going to get it up that high.

Maybe some milled 5.3 heads with 0.040 gaskets will get you just about to 10.0:1.

 

5.3 heads would be the cheapest route...personally I don't think the thinner head gasket from cometic are really worth the money since milling heads will get you there quicker...

If I was you I would get some Texas speed 5.3 heads and if you still want more then mill em...

 

There are plenty of kits available for the GTO both new and aftermarket, what is your budget?

 

picked up some afr 225's, forcing me to buy charger