What I know about methanol is to shoot for 15.0 to 1 or slightly higher for drag racing. I have freshen a 572 race gas motor that had 15.0 to 1 with flat tops with a set of 440-1, I don't remember the CC of the heads though I like and use steel rods, that compression ratio is not hard to achieve with a big C.I. motor with flat tops with valve reliefs I had a set of B1 with big combustion chambers, around 72 CC, Koffels wanted to make them 51 or 52.0 CC , if I'm remebering correctly Check your CC first before ordering pistons