High-horsepower diesel trucks with aftermarket turbochargers will typically display damaging surge characteristics that BD's Turbo Guard can prevent. This blow-off valve protects stock or aftermarket turbos from surging and, thus, the resulting compressor wheel explosion. Turbo Guard has a microprocessor with SIX settings tuned to your application including, Valve Opening Pressure, Valve Opening Duration, Activation Sensitivity, Clutch Cancellation and More! A truck's throttle position sensor is used to activate Turbo Guard, which results in a fully controlled blow-off valve. Toggle and micro switches are no longer needed. TPS/APPS-equipped 12 and 24 valve engines on automatic and standard trucks can benefit from the added protection of Turbo Guard... the only proven diesel blow-off valve in the industry. Note: Not for sale to licensed California vehicles.