I found this online calculator:
http://www.csgnetwork.com/compcalc.htmlBut I don't know my numbers for some of what's requested, i.e., head gasket bore diameter, piston dome volume, and piston deck clearance. I found numbers for everything else, and left the fields I just mentioned with the values supplied by the calculator: came out to 15:1+. I'm going to go out on a limb and guess that ain't right.
Something I should have mentioned, I'd like to keep this thing running on pump gas. So I don't want CR too high, right??