10-4 Smokey, don't know what to compare too but a Taurus 2.6 (totally unfair) but I will give you the RPMs and prop size. There appears to be quite a following already on this combo, search here on RCU for Tubo-Jet. I'll put up pics of the cowl when installed too, looks like it may just fit with no cowl cutting. Dave was turning 7200 on a 18-10 Zinger Pro and the Bison muffler, totally rich.