I'm building a world models 1/3 scale J3 Cub ARF as we speak....I decided to run a Zenoah GT 80 and cut the cowell to expose the top of the 2 cylinders and plugs. Alot of guys are running g62's and they claim that it is plenty of power. These are weighing in at 26-29 lbs fly ready. I wanted alittle more power so when I put it on floats it will have the power to get me out of trouble if need be.