RE: Engine for 60 Ultra stick?
The Saito FA-100 4-stroke is the ideal mate for this plane. It will give it all the power you want and then some and is a very reliable powerplant. If I was to go with a 2-stroke then I would be looking for a high-end 60 or 90. Anything larger than the 2-stroke 91 is very much overkill for this plane.