GCG's Adjustable Pressure Relief Valve is an adjustable over-boost protection valve, used for turbocharged and supercharged applications. Primarily used as a safety valve on many street/race vehicles in the event that a vacuum hose blows off the wastegate, or the turbocharger/supercharger goes into an overspeed/overboost state.
This boost pressure relief valve can be used on diesel, and petrol applications (plenty of these used on the ZD30 Nissan Patrol's which are common for overboost issues when the engine's boost sensor fails). This pressure relief valve is adjustable from approx 1psi, to 29psi, and adjustment is extremely easy using the adjustment screw and locking nut. Mounting thread size is 1" BSPT.