I think that I will build it to spec at 0 incidence all around. It sounds like per sig that the ballooning may be coming from the high performance 46 two stroke combined with the flat bottom wing. I found a Magnum 52 four stroke for $129 and I think I will buy it and use it for my engine. I just don't think that I need to overpower this little plane. CafeenMan, what have you used for motors in your previous two Smith's? What type of flying do you like?