TCI Transbrake Valve Bodies allow you to achieve maximum torque converter stall and provide for quicker and more consistent reaction times and 60-foot times. This is due to the transbrake action which prevents an engine's torque load from being transmitted through the drivetrain prior to launch. The transbrake acts in much the same manner as a manual clutch. Once it is engaged the vehicle can neither roll forward nor backward and as you press on the accelerator the engine can RPM as high as the torque converter stall. Once the transbrake is released the power is transmitted immediately to the rear tires in much the same manner as a manual clutch but with the parts saving advantage of the torque converter's shock absorbing action.