Tony, I have one on a SIG Somethin' Extra. I tried a dozen different props, and ended up staying with the first one; an APC 13x6.

Be aware that the amount of nitro you're running plays a BIG part in how this engine responds to different propellors. Mine ran like crap with a 14x4W on 15%. My buddy runs a home-brew 20/20 mix and his screams with that same prop on his DP Ultimate.

He also had an Aresti; that's a fast little plane. The 13" prop might pose ground clearance problems. Just remember that the higher the prop pitch (if you have to go to a shorter, higher pitch prop for ground clearance) the faster the airspeed. I seem to recall that an 11" prop was the longest that would comfortably clear on the kit gear- he had a TT .46 on his.

That would call for an 11x8 or higher; and you'll have a rocket on your hands...<G> The good thing is that this engine is perfectly happy at higher (11,000+) rpm, so you can run the shorter props with no worries about hurting the engine.

Steve