hi was wanting some input for the guys flying the razzle with a 4 stroke 91 on it. i am flying mine with an os 91 4 stroke with a apc 14-4w prop on it half throttle is all i can do otherwise the plane builds up too much speed just looking for some other possible props. i am running powermaster ys 20/20 fuel and turning around 9600 rpm on the ground the motor spools ok but could use a little faster spool up.well thanks for any help this is a nice flying airplane.