Wilwood's GM style proportioning valve is a direct replacement for 1978 and newer General Motors vehicles equiped with front disc / rear drum brakes.Manufactured from high quality aluminum and coated with a durable black anodized finish. Line connections for the valve, if mounted in the OE location, Will allow the original lines to connect directly to the valve. If mounted in a non-OE location, fluid lines may have to be modified. This also does allow usage in other non-GM vehicles. This proportioning valve offers: 63% psure reduction (rear) after 350 PSI knee point. A 30 PSI delay rear-to-front circuit and Circuit failure sender activation at 50 ± 10 PSI. A Recommended maximum operating pressure: 2000 PSI. Non-adjustable front-to-rear proportioning (knee point, rate, etc.) and Anti-dive or metering delay valve: Enables rear brake pressure to build momentarily before front brake pressure builds.