Cyberwolf, sounds like that new piston for the Mintor 22cc engine you made is going to work out just fine. Good Work. About raising the compression ratio, it may just only place more stress on the engine. Not sure on that. See if you can go to the engine conversion forum & look for AV8TOR. He has ported many engines and seems to know a lot about porting & compression and the effects it has. I have really enjoyed trading ideas with him. We did a lot with gas/glow engines also. Keep up the good work, wish I had the range of tooling to do more with engines....its very interesting! Best Regards Capt,n from W Michigan