In this video, we learn how to tune an RC nitro engine. First, you will need to adjust your needles. Make sure you know which way to go as you are adjusting them. After this, you need to find your high speed needle and find where you will hook up your fuel line. Lean the motor by turning a screwdriver into the barrel. This will screw your needle in and make the engine restricted to fuel flow. Now you will want to test out your engine to see how much lean you are getting. Make sure it's oiled up properly, then enjoy!