On orders over $99
100% Money Back on Select Parts
Product images
Product Media
COBB Tuning LF Bypass Valve - Subaru Models (Inc. STI 2004+ / WRX 2002 - 2007)
COBB Tuning LF Bypass Valve - Subaru Models (Inc. STI 2004+ / WRX 2002 - 2007)
COBB Tuning LF Bypass Valve - Subaru Models (Inc. STI 2004+ / WRX 2002 - 2007)

COBB Tuning LF Bypass Valve

Subaru Models (Inc. STI 2004+ / WRX 2002 - 2007)

Read 4 Reviews | 1 Q&As
Part # 712665

Ships within 10 days

Features & Product Details

RallySport Direct is proud to provide you with quality performance and racing products brought to you by COBB Tuning. 


Here, you are looking at the COBB Tuning LF Bypass Valve. This is a compact and lightweight by-pass valve that has been designed to hold high boost pressure without leaking. This is a great option for those with stock or heavily modified vehicles and wants a by-pass valve to be the last by-pass valve you will need.



  • Updated design reduces control volume by 30% allowing for extremely fast venting of boost when actuated
  • Compact design allows fitment in a confined engine compartment
  • Lightweight components create less inertia and can respond faster than heavier components
  • Uses banjo-fitting vacuum port which provides 360-degree adjustability of hose routing
  • Piston O-ring seal is twice the diameter of the old design allowing more seal compression and reduced wear
  • The adjustability of the spring seat is no longer needed to the updated spring and seal design which provides a 60% increase in clamping force at peak boost while maintaining similar operation at idle and transient loads




    Brand: COBB Tuning
    Color: Black / Silver
    Design: Piston
    OEM Replacement: Yes
    Valve Type: Recirculating
    Mfgr. Warranty: 1 Year
    Condition: New Product
    Return Policy:
    RallySport Guarantee



    4 Reviews
    5 out of 5 Stars
    5 Stars
    4 Stars
    3 Stars
    2 Stars
    1 Stars
    Customer Photos and Videos
    No user media. You can upload a photo or video of your install by posting a review.
    Buy this thing. 2 months ago
    5out of 5stars

    First of all, one of Cobbs best pieces. This thing is craftsmanship. After installing my FMIC I noticed my stock bpv was not able to handle the extra volume of air in the system and was causing the car to jerk on light throttle release. When I pulled the old one off, the valve itself proved very difficult to push in by hand. The Cobb one is super light and responds to light pressure smoothly. It sounds like stock but a bit cleaned up, but completely fixed the jerking. Car drives better and I’m able to row through the gears so smoothly now. Buy this now!
    Was this review helpful?
    Superb Quality 1 year ago
    5out of 5stars

    Very solid and well-built piece of equipment. Venting feels ridiculously immediate upon release of the accelerator, which is great. I doubt that I'll ever have to replace this.
    Was this review helpful?
    BPV 1 year ago
    5out of 5stars

    Solid piece, does just what it needs to and looks much better than the stock unit.
    Was this review helpful?
    1 of 1 people found the following review helpful
    2007 Subaru Forester Sports XT 2 years ago
    5out of 5stars

    I decided to leave a review on this since I couldn't find any when I was shopping around. My Forester had the original stock unit despite having a VF39, other mods, and a tune. I had suspected the OEM bpv may have been struggling to hold pressure, and this install proved me right. The car instantly felt much better and sounds great. Make sure you pick up a gasket with the purchase.
    Was this review helpful?


    • Q: Adjustable to eliminate compressor surge?  Steve B 2006 STI3 months ago

      From reading the description, it sounds like this valve adjusts itself to avoid compressor surge. Is that correct? I'm looking for an adjustable plum-back valve to tune out surge and the fluttering sound it creates.
      • 0 of 0 people found the following answer helpful

        A:  This will be a more responsive bypass valve, which should help reduce compressor surge, but it is not user adjustable.

        Lane H. @ RallySport Direct 27 days ago  
        Was this answer helpful?

    This Part Fits