I'm happy for this thread to take a auto/motorcycle engine conversion turn, but I want to make it clear that the UL Power engines were designed from the ground up as aircraft engines. That said, they are not cheap (although the UL260i is a little cheaper than the 912S at the moment) and more importantly to me they would undoubtedly take some "tinkering" with the installation and prop to get it right (and I don't want to spend my time or money doing that). That's why I'll probably go with the 912S in my SS7, although I don't share the enthusiasm many of you seem to have for that engine (I hasten to repeat that I have 200 hours flying behind a 912S). I encourage all of you to take a look at the UL Power website (I'm still hoping someone will put one on a Kitfox so I wouldn't be the first).