How heavy is the plane. Your probaly looking at about 6lbs built out of the box. My kadet flys great with a .46 OS FP but is not a speed demon. It gets great duration on a full stock tank. The engine rating is .29-.40 cu. in. 2-Stroke. So a .46 ABS ball bearing type engine with a speed prop such as a ASP shoud satisfiy your requirments.