In an attempt to upgrade this season, I went to a 15x10 three blade prop, replacing the original two blade that was on the boat when I purchased it. When it was installed the boat made smoke (over proped)and only turned 2700 RPM's. After adjusting the pitch down to 15x9 I was only @ 3070 RPM and it still made smoke. I reasoned that I probably should not take another inch of pitch out of it and loose the "bite" I went to the three blade for. I returned the prop. Does anyone have experience with this particular boat with the M-18 Universal and a the dimensions for a three blade prop? Thanks for the help/