You're a lot more likely to get off the ground with something like the Rotax 447:

http://www.rotaxparts.net/scripts/pr...p?idproduct=33

It's about 40hp and of course has a bunch of gearbox options. You can swing up to a 66" prop at a more reasonable 2500 rpm or thereabouts. I've flown a couple 447's, good engines.

The DLE would be super loud too!

LS