So I have an extra 2150 kv motor I stuck on this Spartan ,with a 45mm prop it was not much fun ,so I stuck on a 640 because of the speed of the motor ,man it was smooth ,no torque roll ,no chine walk ,had the strut straight with the hull ,at speed just the tail was in the water ,never did hitter speed ,it would blow over,need to lower the strut a little ,but this prop makes all the difference with a fast motor on 6s,small prop with a lot of pitch ,I'm leaving it on ,