RE: FT-160 Twin in Vario Boxer Heli
With the twin-cylinder engines, one cylinder will ALWAYS be leaner than the other. You just have to set the engine so that the leaner cylinder is not running too lean, and let the other one take care of itself. It's a fact that multi-cylinder engines will not get even fuel distribution unless you have direct fuel injection to each cylinder. Full-size aircraft will show the different cylinders with different exhaust gas temperatures when normally-aspirated. That shows an uneven distribution, and you lean the engine to the cylinder that runs the hottest...same with model engines.