Important! Please Read Before Purchasing Any Blow Off Valve! Here at Treadstone we strive to provide our customers with the best possible service, and help them make the best possible chose when it comes to turbocharging any vehicle, and as such we try to inform our customers as much choice as possible. So today’s topic is BOV springs and the common misconception you might face with them. Misconception: 1) All BOVs are the same, in reality there are many different types and styles of BOV on the market each made for different styles and configurations. From the popular pull-type HKS to the new 50mm Tial Q BOV all have their pros and cons. 2) A BOV is not always needed; the truth is that a BOV enhance the turbochargers’ overall lifespan by alleviating detrimental compressor surge thrust loads during closed throttle or high vacuum conditions. 3) All Vacuum is the same, in reality not all vacuum line are the same a vacuum line before the throttle body experiences very little to no boost while a vacuum line after the throttle body sees both boost and vacuum. So when choosing your reference line make sure to keep this in account, or else your accessory systems my not function in a manner you would like them to. 4) The BOV spring must match the boost spring, this is the most common misconception in actuality the BOV spring must match the vehicle vacuum at ideal this allows the BOV to open when the throttle is closed rapidly. For instance if you have a vacuum pressure at ideal is -20 In/Hg you would use the -11psi spring in your Tial Q BOV, on the Other hand if you had -8 In/Hg of vacuum on ideal you would use the -6psi spring this allows the BOV to open as soon as the throttle closes. [gallery] When ordering any performance product remember that information is your greatest asset and here at Treadstone Performance Engineering we are here to service all of your need.