1/4 scale cub engine
PS, Old Mill, you may want to consider chopping off your wingtips, then removing the last 2 rib bays, and then gluing the tips back on. Every cub I've ever seen with the full sized wing has a tendency to have adverse yaw in turns, It's like the wing is too big for the plane. That's why the "Clipped Wing" version is so popular. And the clipped wing is certainly no more difficult to fly. If anything, it's easier due to the lack of adverse yaw.