My Four Star 60 is the ARF version. Power is the Magnum .91 4 stroke turning a 14x6 prop. I built a new rudder that is 1.5 inches bigger, replaced the stock pushrods with carbon fiber rods, and used titanium prolinks and ball ends on the aileron linkages. With the power of the 4 stroke and the larger rudder, it will sustain knife edge flight with ease, and it really improved other aerobatics as well.
