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

SKU 126022.1
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 the ground-up design with the valve body and base for each popular fitment. Both are CNC-machined out of billet 6061 aluminum alloy for its strength and light-weight. 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, we 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, all of our 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, they employ a swivel fitting 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 aftermarket intercoolers, and in 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 install and for accommodating custom setups
Requires Aftermarket TMIC, does not work w/ OEM intercooler

Customer Reviews

Based on 1 review
Great product

Grimmspeed always has the best quality, fit, and finish. Install was super quick and easy. Definitely an upgrade from stock as I could instantly feel a more consistent response from the car. ....and the thing everyone asks about, it sounds great!


We appreciate your 5 Star Review! The Grimmspeed Bypass Valve is like you said, definitely an upgrade from stock! The billet aluminum alloy construction makes for a solid piece that looks amazing! The huge 38mm piston improves performance and ensures reliability to your turbo!