I know an MVVS/Evolution 26 will turn a 18x6 around 8700-9300 rpm on a tuned pipe. I'd really like to put this .90 in something, maybe modify a Perfection to be a 3D plane. I also like the sound of the 2300 converted. I almost bought a 2300 for my Wild Hare 120 Edge, but they're so variable in that some are good engines, some aren't.