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Grimmspeed Bypass Valve Red 2008-2014 WRX w/ Aftermarket TMIC / 2005-2009 Legacy GT w/ Aftermarket TMIC

SKU 126022.2
Sold out
Original price $249.00 - Original price $249.00
Original price
$249.00 - $249.00
Current price $249.00
Here, you are looking at the Grimmspeed Bypass valve for your 2008-2014 WRX / 2005-2009 LGT with an aftermarket TMIC. 

Grimmspeed started a ground-up design with the valve body and base. Both are CNC-machined out of billet 6061 aluminum alloy for its strength and light weight properies. They are then anodized in either a black or red finish to give them a brilliant appearance, provide corrosion resistance and match other GrimmSpeed offerings. Compared to the stock plastic construction on the 08-14 WRX platform, GrimmSpeed Bypass Valves not only stand out, but are guaranteed to stand the test of time.
For the internal components of the valve, Grimmspeed chose to utilize a machined brass piston for its anti-corrosion and low thermal expansion characteristics.

The piston seats onto an internal o-ring to create a perfect seal, eliminating boost leaks common in OEM and cheap aftermarket BPVs.
In order to make sure this could keep up with high power levels, Grimmspeed chose to use a massive 38mm diameter piston/sealing ring for the ability to dump pressure quickly. This is especially important on high boost applications to keep the turbo from sustaining damage and the BPV maintaining leak-free operation.
A precisely-tuned steel spring alleviates the need for any tuning or adjusting of the valve, with no engine tuning required to run the unit.

Buna-N O-rings were the next logical choice due to their resistance to degrading from fuel and oil exposure. In addition, the o-ring grooves utilize a single dovetail design for superior retention. This guarantees the o-ring will not fall out and has the perfect crush for sealing the body together. To top things off,  a swivel fitting is employed on the valve to make for easy installation and accommodate best routing on custom setups. A GrimmSpeed signature branded badge graces the top of each unit so that everyone will know you chose the best valve in the biz. 

With the GrimmSpeed Bypass Valve installed, a definite crispness and sound change is noticeable through the intake and due to the leak free nature of our valve, the car builds boost much more quickly over the leak-prone OEM version. Both the 08-14 WRX/05-09 LGT and 04-21 STI (EJ) fitments utilize the same valve but with different footprints, for use across a broad range of vehicles including Legacies, Foresters and Bajas with the proper intercooler setup. This listing will include the specific footprint for 2008-2014 WRX / 2005-2009 Legacy GT using aftermarket intercoolers. This configuration will not work on your factory intercooler, or an STI style system.


  • CNC-Machined 6061 Aluminum
  • Corrosion-resistant anodized finish, available in both red and black
  • Oversized 38mm brass piston for superior flow Precision-tuned steel spring for long life
  • No tuning or adjustment required
  • Single dovetail o-ring grooves with Buna-N O-rings for great oil resistance, retention, and leak-free operation
  • Swivel air fitting to aid in installation and for accommodating custom setups

Requires Aftermarket TMIC, does not work w/ OEM

      Customer Reviews

      Based on 1 review
      Ayden Phares
      I love this product

      This product is amazing when combined with a cold air intake the flutters and blow offs are like music to my ears. The tone of the bypass valve is perfect and gives that nice touch to your engine bay with the amazing red paint!


      The Grimmspeed Bypass Valve is a great upgrade for your WRX/LGT with an aftermarket TMIC! The billet 6061 aluminum alloy external construct along with the brass piston inside ensures durability and longevity especially over the OEM plastic! This design ensures reliability for high boost/power applications by using a huge 38mm piston that alleviates pressure extremely quickly! We appreciate your 5 Star Review!