Thanks Arobatx for your answer, that gives me a better perspective.

To give you guys a better idea of where I'm going on this, I'm looking at a 1/4 scale Wing Derringer twin with an 87" wingspan, 1137 sq. in. wing area, and a projected weight of 24-27 pounds. They recommend .60-.75 2C glow engines.

I'm basically trying to avoid using glow and just use gas. Would I possibly be okay with something like the Zenoah G-20? Or does anyone have any other recommendations?

Thanks