BTW, the guys at our field who run OS46AXs have gone to 11x6s for most airplanes. And I'm running 11.5x6s on most of mine. The engine is a bull. It'll run a 12x6 on a couple of my smaller birds, but the vertical suffers on the regular sized planes, meaning that's too much prop. I like as much fan (diameter) as possible, so tried a cutdown 12x6 one day. Took the balancer to the field and took 1/4" off each test. At 11.25" that particular 46AX had just started showing a bit of loss on vertical, so I figured to save that prop for winter flying (air is denser) and made up some 11.5s I was trying some 12x5s but although the vertical was excellent, I didn't like the obvious loss of speed that was accompanied by obviously higher rpm. No value in that.