I was told just the other day by a guy that has his own shop and has been in the hobby 50 yrs that the only true way to tune the engine is to fly it and make sharp turns and climbs and listen to the engine and adjust as you need. I'm new to the hobby and I've found out that everyone has their own way of doing things. I have someone hold the plane and I throttle up and have them tilt the plane up like climbing and hold for a min. then tilt it down and hold it for a min. and listen for any changes in the engine, and then fly it and listen to it in the air while you climb and make sharp turns,,