I would think it would do better.... I threw an Echo 58cc together a while back and it turned a Top Flite 22 x 6-10 at 7000.

How is your ring gap?? Another thing that can trip one up is getting full throttle. We usually remove the stop from the throttle and set the idle with transmitter trim. That's fine, but you have to watch that the throttle butterfly doesn't open TOO far and go past center, actually closing the throttle somewhat. I once had one that was a bit down on power, and found out that there was just enough slop in my throttle linkage that the engine would suck the butterfly partially closed while running....

Just looked up your carb.... On that size engine it wouldn't hurt to go to a 15mm carb, but check everything else first.

AV8TOR