Hill, great to hear about your successful maiden but I think that's too much prop for that engine guy! I know it's not a true comparison, but for example I'm running a Saito 150 single cylinder (which is just a tad smaller in displacement than the 160 Gemini) and I'm swinging a 16 x8 at 9300 rpm full bore. Needless to say, my full wing DPSC hauls ***** and I have to throttle back to fly it scale. Everybody at the field tells me that it's overpowered, and it is, but I'm saving all that power for when I put it on floats, I'll need it then he! he! You might want to try a 16x8 or 16x10 and see how it goes. On another note that's the scale size prop for the Cub!