what is the piston dome c,c in a stock 500hp carb motor.

my heads im using cc at 122.5

not for certain however I think flat tops and you would have near 8.75 to 1 depending if you have stock bore

I don't know the specs on the pistons, but the stock heads are 118cc. The increase in cc is going to lower the Comp Ratio to about 8.4:1. Use a thin Cometic head gasket.