TCI Automotive Brake Proportioning Valve 861730;

These dependable, quality units provide first-class performance as braking devices. When installed in-line with a vehicle's front brakes, the TCI RollStop allows you to do a burnout like the professionals. Simply pump up the brake, apply the RollStop and release the brake pedal. It will keep the front wheels locked. If you did not pump up enough brake pressure - no problem - simply hit the brake pedal and the unique one-way valve puts additional pressure through to the wheel cylinder side. The RollStop can be installed without brake system modifications and includes a precision micro-switch that releases the front brake and can be installed anywhere in the car. And now TCI offers application specific RollStops for certain Camaros and Mustangs.