Mustang Wilwood 2lb residual pressure valve retains a minimum brake line pressure to help eliminate excessive pedal travel in brake systems. The two pound valve is used where pad knock back occurs, thereby causing excessive caliper piston retraction and a longer brake pedal stroke. Pad knock back is common in rear disk brake situations where a full floating housing is not used. Due to the cornering loads the brake pad can become “unseated” and must be reset by reapplying pressure, this leads to decreased lap times and complication. By using a 2lb residual pressure valve constant pressure is put on the pad, while not over-applying pressure causing brakes to drag.