I agree with Todd about no overheating problems. Even standing still there are no overheating problems. A friend of mine was holding the nose of my CBM F-16N as I warmed up the engine and he said that he could feel a strong inflow at the chin scoop when he put his hand over it. The prop being so close to the tailcone is probably what allows the good duct-flow even standing still. Since there is such good suction at the chin scoop, I imagine that air is also being drawn in between the engine head and engine head cut out hole in the tailcone. I have another pusher without any sort of ducting around the engine and I do have problems with overheating when I static-run it.

I also agree with Todd about recommending the YS 45 for this plane. But I would also strongly recommend a tunned pipe. My first flights were without but, it is just so much more fun with the pipe.