I stopped by the LHS this evening just asking around and the guy there said that usually a multi cylinder wont pull the kind of power that a single cylinder will, that the FG 60 would be more like a 55 CC and the Hellcat being around 27 pounds might be a bit underpowered with it. He said it would fly it but you would be spending most of the flight at 3/4 to full throttle and you could get into trouble if you need power quick.. a lot to think about so I may sideline this project for a bit. On a side note, sitting on the shelf there was a 15cc Hellcat ARF.. I did not know Horizon had put that out.. been doing the Harley thing all summer and have not flown this year. I am biked out so I am getting some planes around now but that would be an interesting project.