Mangum 46, that a 2 stroke? I had a 46 OS FX on my last one and flew great. Actually the engine pylon is still in tact (after the crash) and can be plugged right into the new one if I don't to finish up my new engine setup yet. For flight testing I suppose. Or maybe I should not in case the 4 stroke doesn't fly as well. Planning on an OS Surpass 52.