Abstract: An improved turbocharger system including a plurality of selectively actuatable pressure switches and associated vent valves on the compressed charge side of the turbocharger so as to allow a selected reduction of boost pressure. The several pressure switches serve to control the operation of solenoid actuated valves in the charged flow stream leading to the engine intake. The pressure actuated switches have graduated thresholds such that during normal operation, they provide progressive actuation of the valves at higher pressures. A switch is also provided which allows selective deactivation of the high pressure switches and activation of other low pressure switches which serve to reduce the charge during cruise operation. The vented charge may be dumped to ambient, may be recirculated to the turbo input, or it may be routed to the inlet of the compressor in opposition thereto so as to prevent possible runaway of the turbocharger.