crank,

Good advice to use a tach to help compare different props. And of course to fly them to find out which ones make the plane behave like you want it to. I like Chuck's idea about trying to make these OOP engines last. I'm gonna try some 13 inch props on my SF/RFs. Maybe tomorrow on the test stand. My <7lb. monowheel Calypso flies great with its OS FS90 turning an APC 13~8 near, IIRC, 10K.

Terry in LP