I just finished installing a new set of servos and fabricateing a new spur gear setup for the GT. I got just a standard hitec servo for the throttle and a futaba 3305 high torque servo for steering. the spur gear is a 44t gear that I think is for an old HPI RS4 I found it in a tool box that I got as part of a package deal a while back so I'm not sure exactly what it is for but I made it work. so now I am running a 44T spur with a 19T clutch bell this thing is going to fly!!!