I'm flying a Trex 450 in a Hughes 500E fuse. When I add power quickly the nose yaws left just past 90degrees due to the torque. When I drop the throttle the nose will yaw right less than 90degrees. I'm running a GY401 w/S3154 and a DX7. I was told that I should run a 5.1v step down for this servo when using the GY401 so I installed a step down and getting the same results. Did I already blow the servo or is there something else that I need to do?