Joe,
You probably already mentioned but Imissed the type of plane you have this motor in. That prop is rather small in comparison to what a lot of us run. Your plane will dictate what you run but that motor will turn, at the very least (as I've tried them all) these props:

APC 20x15
20.5x14
22x12

Falcon 21x14

Obviously, it'll turn a lot more but those are the props I've tried. I'm surprised you have to go full throttle (or maybe this was just a ground check).


Good luck at the contest!