Inefficient factory blow off valves (BOV) can hinder boost response during shifts and can damage your expensive turbo charger. PERRIN offers several choices for owners to choose the best solution to the problem. Fully recirculated (Recirc shown) For clients that demand proper air fuel ratios and idle quality we offer a fully recirculated BOV. The internal design allows the user to change the volume of recirculated air, spring tension and sound. It also incorporates an industry leading boost chamber that does not place pressure on the piston surface that would otherwise force it to open prematurely. It will only release pressure when shifting. This condition is common with our so called competitors, leading to serious tuning issues and reduced power. Capable of handling more than 190 psi, there simply isn’t a boosted engine that our BOV can’t handle.