Figure my compression

I am running spitfire headers into 2 1/2" out the back. Eddie rpm intake, eddie 750. I never thought about polishing and cleaning up the heads to increase the volume. I sure wish I could turn back time and make the heads about 60cc. Who knows, I may spring for some eddie heads this spring if things don't work out. Especially if I have to run special fuel just to get down the road.