I had two Brison 3.2. I had the best performance in the air when the engine tached 7200-7400 rpm on the ground. The props I used to accomplish this were: BME 22x8, 3W 22x8. Menz 22x8, NX 22x8, Mejlick 22x8. The MSC 22x8 loaded up a bit more @ around 7000 rpm. but pulled like a horse. Good luck.