This valve is a direct replacement for the Bosch valve as used on most German factory built turbo automobiles, e.g. VW Golf 1.8T / Audi TT / Porsche 911 Twin Turbo. The Bosch valve is made from plastic and contains a rubber diaphragm which is actuated by engine vacuum. The valve is used to release pre-throttle body manifold pressure on deceleration.

The VF-Engineering Race Bypass Valve is made from billet aluminium and can withstand higher boost pressures and the higher charge temperatures. The OE Bosch valve is a part that is prone to failure in stock applications and particularly on 'chipped' vehicles. Bosch have revised their valve design several times but by using the VF-Engineering valve you will have the assurance that once this valve is fitted, it will not need to be replaced.

The VF-Engineering Race Bypass Valve has been bench "flow tested" and results show that it flows just over 10% more capacity. The greater airflow capacity means that on aftermarket and higher boost applications, air turbulence is reduced and the possibility MAF turbulence is minimized.

This valve is supplied with all VF-Engineering stage 2 supercharger systems and is recommended for all stock and modified vehicles fitted with either superchargers or turbochargers.