When you get your new engine or rebuild the old one I recommend you add 2 to 3 oz of extra oil to the first gallon fo fuel you use through the engine. Open the high end needle 2+ turns to where the engine will barely run its so rich. Keep it here for the first tank then lean it to about 1 3/4 turns. Once you have 3 to 4 tanks burned richen the bottom needle until the tngine will not idle well and then back it down until it will idle. The OS 32 needs to be rich on the bottom end as it effects the hover settings. If the engine coughs while transitioning from idle to running RPM's this is a good sign that you are in the ball park for the bottom end setting. If it dies while transitioning lean it no more than 1/16th of a turn at a time.