VIWG Borg Warner Wastegate Actuator 57mm Diaphragm – 6inHgTurbosmart Upgraded Vacuum operated Wastegate Actuators have been developed to provide maximum possible boost response for your factory frame turbocharger. The Turbosmart vIWG Series of upgraded Actuators benefit from an increased 'Working Ratio' over the factory equipment resulting in improved boost response, throughout the RPM range. This Improved 'working ratio' is achieved through an increase to the effective surface area of the diaphragm &