Thanks for the feedback guys. I tried a 10x6 and I got too much cavitation, a lot of RPM but not pushing much air. I do understand that humidity and all will affect the performance, I was enquiring so that I can get a baseline guide to work with. Was my first time buying the engine and I was more of testing it than anything else. I have to say the SC is totally reliable, does not cut on me even when its running inverted. The power is less but the price is even lesser! I just got a SC 91 2C yesterday for my pattern plane ... hope it turns out well ... thanks a lot guy for your input!!!

ps. the SC is actually OEM for Magnums.