The perfect engine for a 1/4 scale Cub is an FS 1.2, the main problem with this size engine for the Cub is not that it will overpower the airplane, a throttle takes care of that, but the size is much more than a Cub nose can handle, although some people don't care about that, to me is very important.
My Bellanca 1/4 scale Decathlon had a Quadra 35 for power (much larger nose area than a Cub), and it was just perfect (at 20 lbs ready to fly weight), I've also seen 1/4 scale Nosen Aeroncas with this engine and it fit OK too, that engine will power just about any type of airplane up to about 15-25 lbs. weight, but then again if you want a 27 % (82" wingspan) Extra or Cap that may only weigh 15 lbs but you want to do 3 D manuevers with, it would probably be not the right engine for it, it would fly them very well, but not 3 D.
Most large biplanes and high wing type airplanes would be the best aircraft for that type engine at the weight I mentioned earlier.