0Re-designBest Answer 9 years ago ReplyUpvoteIf you want the plane to go faster find the max. rpm point of the motor. Then vary the pitch of the prop. A steeper pitch will go faster if the motor can pull it. A shallower prop will give more power to climb but top speed may be too low. There are charts with guidelines available on electric r/c sites that will help you figure out the best prop size and pitch.