Just so I'm clear, you believe that with a 4.0 inch stroke and the 4.0 in diameter pistons that I have, my compression will be 10.68 to 1 with the magnum heads that I have since they actually measure 64cc's? I guess iron heads would be out of the question then for pump gas?

If my math is right and I just used the stock crank 3.58 my compression ratio would be 9.67 to 1?

A 3.79 stroker crankshaft would bump the compression up to 10.17 to 1?