Manual boost control valve, acts as a safety to ptotect your turbo in case of a control system failure.
Ok so, what is it?
The Boostvalve turbo boost controller is an adjustable pressure relief valve or "check valve". Some may call this a "gated valve", but be certain it is NOT a "bleeder valve".
In simplest terms: It prevents boost pressure from opening the turbo's waste gate until the desired preset boost level is reached. Inside the valve is a precision stainless steel ball that is held in place by spring tension. During the turbo's spool-up (as pressure is building) spring tension in the valve is greater than the boost pressure pushing against the ball, so the ball prevents the air from flowing to the wastegate actuator.
This maximizes the efficiency of the turbo during the spool-up by using the greatest amount of air possible to spin the turbo charger. Most boost control systems waste air by venting much of the air out, even many factory boost control systems waste available exhaust energy during this crucial spool-up period. Once the turbo spools up to the desired boost, the Boostvalve opens, quickly opening the waste gate. Boost pressure is held at this level with accuracy unmatched by even more expensive methods of boost control.
Alright. So, why is it better than a "bleeder"? A bleeder valve is open all the time. Bleed valves work by fooling the waste gate into only seeing some of the boost pressure. The rest of the pressure is vented off, sometimes completely wasted by blowing out an open hose. Just like an air leak in any other hose this wasted air can cause problems with modern computerized engine controls. Additionally this causes the waste gate to open before maximum boost which can create turbo lag.
boost valve