I used a CRRC26V2 on mine. Power is great. Fit the cowl with only the VVRC pitts muffler pipes showing plus a hole for the velocity stack and spark plug. Engine isn't terribly obvious. Not unlimited but plenty of power for a very tall hammerhead, large loops, and good takeoff climbout. Don't really need more. Motor isn't totaly broken in, and I haven't played with the props yet. Should get better. 16x8 Zinger for now until the weather warms some.