I am looking for a gas engine to put into a 60" bipe that should come out around 10lbs with out engine. This plane use to fly with a Webra 120 (30oz with muffler) but did not have the power to fly out of a hover though it could do just about everything else. I know the g-23 and the 3w-24 does not have the vertical that I am looking for so:

My question is what is available?

Is 40cc's to much? That is really the next level. The only 30cc I've seen is the RCS 1.8. Would that be enough?

Suggestions.