RE: McCoy 35
I flew a McCoy redhead 35 in a Sterling Yak 9 for Old Time Stunt. For a long time the engine took only one flip to start. I put a lean run on it (all castor fuel, I'm sure). It still ran the same, but took three flips to start from then on. I thought the McCoy perhaps a little better than the Fox 35, perhaps not. Any way, I got rid of the McCoys and kept the Foxes because of parts availability. I still have several McCoy 19's and have flown the hound out of a couple of them. I really like them.
If I have wind up or runaway problems, the first thing I do is change propellers. I've been able to solve the problem that way several times. Easier than fooling with head shims or venturi size, maybe.
If you are beyond the beginner stage in control line, a Brodak Flitestreak would supply hours of fun with your McCoy 35.