1.5T 10th & 11th Gen Civic/Integra Billet Bypass Valve (BPV)

When any 27WON projects start, the first question we ask ourselves is always “why” as in “why develop an upgrade?” In this case, the answer was clear. The stock Honda bypass valve is a weak point and had to go! We know customers want reliability and our community pushes the limits on what they can get out of their Civics for power and performance. Those two things mean a lot to us. So, our solution needed to be robust, reliable and also stand-up to increased boost pressure.

With that principle guiding us, we set out to REDEFINE what a bypass valve should be. We started by ditching the cheap OE style stamped steel body. In place we went Billet design. Next on the list was the actual interior bypass mechanism. Instead of a flimsy rubber diaphragm, we opted to use a metal piston. Finally, we knew we had to make this mod work with the OEM factory turbo and also aftermarket turbos like our W1, W2, and W3 to maximize compatibility and allow our customers to grow with this mod as their builds progressed. And yes, this will even work with 3rd party non-27WON turbos if you’re running those. Thus, the 27WON Billet Bypass Valve was born.

Let’s talk details. A common weak spot amongst OE style bypass valves is they often develop a tear in the interior rubber section. This may cause boost related engine codes galore and even poor fuel trims. This is especially prevalent on higher horsepower builds and with lots of accumulated miles.

So, out went that style and in went a piston in its place. This allows better durability over repeated use and no opportunity to tear. This piston and its spring work in tandem to control boost pressure when the throttle plate closes like when you up-shift into the next gear. And don’t worry, our BPV will work with both 6MT and CVT transmissions so no one gets left out.

Honda’s cost cutting measures sometimes leave us puzzled. Certainly, they could have made the stock bypass valve look better, right. But, nope! Fine, we took on the challenge. We scrapped the plain boring thin steel design and in its place use Aluminum construction. The valve cap is accentuated with a knurled finish and the top is engraved with a “W” logo to let everyone know you’re rockin' the best parts for your FE or FC Civic and Integra. Form and function meet at one!

10th or 11th Gen Civic 1.5T. Manual or CVT transmission. Sedan, Coupe, or Hatch. Stock or Aftermarket Turbo, OEM or upgraded Turbo Inlet Pipes…this BPV will work across all these different combinations of parts. We wanted maximum compatibility and our design allows the benefit of integrating seamlessly with your current list of mods. And look, if this is your first mod ever, then you’ve come to right the spot to scratch that itch to turn your FE, FC, or FK Civic into the ultimate daily, auto-x monster, or even roll race hero.

Let’s talk boost control for a moment. The OEM valve controls how quickly your turbo spools. What we mean is that it seals the system so that charge air doesn’t escape when you mash the throttle and want power. This is the closed position. On the flip side, it has to open to relieve excess pressure when you upshift or just simply let off the throttle. This is called boost taper. During R&D, we put this valve through the ringer testing over thousands of miles and across different setups to confirm the same or better spool and boost taper characteristics as the OEM valve. What this means for you is 100% drop-in CEL free operation while keeping performance front and center.

Unlike traditional blow-off valves that release excess boost pressure into the air causing that “whoosh” sound, our valve is a fully recirculating design. Why is that important? Because the ECU can't figure out where that missing air went and it compensates by changing how much fuel is being added or taken away. That causes fuel-trim problems. You know, the ones every other Honda owner has told you about when going to a blow-off valve. Not here though. Our design functions just like OEM so fuel-trims stay nice and consistent allowing you to worry about other things, like how much offset is too much on your latest wheel setup!