Greddy Blow Off Valve - Type R

If the throttle plate is closed while engine is making boost, the compressed air will return to the compressor housing which causes compressor surge and also damages the turbine shaft. In the same condition, the GReddy Blow Off Valve will release the copressed air from the charge pipe to protect the turbocharger from the pressure spike and also gives quicker boost recovery. By modifying the vaccum line routing, it can also be used as a Relief Valve.

A blow off valve relieves pressure that builds up in the intake system when the throttle is closed quickly (between shifts, for example). This valve is an extremely important part of any turbo system, and allows quick boost response and greatly increases the life of a turbocharger. Original equipment valves function well, however they tend to be unreliable at higher boost levels. The completely adjustable GReddy S-type valve offers excellent performance at a reasonable price.

Many cars will require some sort of adapter in order to install an after market by-pass valve. BOLTS ONTO 1st generation DSMs with slight modification. 2nd generation DSMs require either the S-type adapter flange or an intercooler pipe upgrade that incorporates an S-Type BOV flange. GReddy also offers the R-Type BOV, which should only be used for high-output race engines in excess of 500hp.