V&H Fuelpak Touring 11-13V&H Fuelpak Touring 11 13 Your fuel injected American V Twin is equipped with an ECU (electronic control unit) that's programmed to deliver fuel to the motor based on an air fuel ratio for a stock air filter and stock exhaust system. While the ECU can self adjust for environmental factors such as temperature and altitude, it can't adjust for mechanical changes like adding performance parts. When you install a performance exhaust system, your airflow