engine for 4-120
 

I am working on an older kit, an Ace 4-120. It has an 85 inch wingspan and the box says it will weigh 13 pounds - pretty heavy for today's standards. I have a 25cc gas engine I was going to use, but I have been interested in the RCV engines and started thinking of getting one for this plane instead.
Would the 120 be the best choise? Would the 90 fly it? I don't care about going straight up or having excessive power, so long as it can loop and roll easily. The kit was designed for 120 four strokes. Thanks Jim S.

engine for 4-120
 

Hello
As long as you are not expecting to do 3D aerobatics the RCV-120 will fly it beautifully. I would use a Zinger 18x14 or 20x12 prop and keep the RPM down to about 4500-4700 revs. If you need to go to a larger prop to keep the revs there than by all means do so. I would strongly recommend that the engine be broken in using my procedure to extend the longevity. Please Please Please use a good fuel. If you have any questions please call me (630)321-0580.

Otto Kudrna