I think there is something wrong with your engine. My Saito 60 Twin will turn a 12x6 APC prop at 9000 RPM on the ground with 15% Nitro. Sounds like you're running on one cylinder. Download the Twins manual from Horizons' website and follow the instructions on how to set the two carbs. It's not difficult but you have to follow their procedure to get good performance. Might not be a bad idea to leave the glow drivers connected while you're doing the initial set-up. That way you'll be sure you're not dropping a cylinder. Also, remember that these are AirBleed carbs. To lean them at idle you unscrew the adjustment (counterclockwise) to let more air into the idle circuit..

If you can't find the manual on Horizon's site E:mail me at [email protected] and I'll send you a .pdf file.

Bob