Good product & easy install
"When I received it I was beyond excited to start working on my car again and it was a straight forward job."
GrimmSpeed is proud to provide the most complete and easy to use 3-Port Electronic Boost Solenoid for available for all turbo Subarus. Unlike your OEM 2-port solenoid, the GrimmSpeed BCS will allow for extremely high resolution boost control, providing your tuner with the hardware he needs to safely tune your car with rock solid boost levels. Using our solenoid, you are able to spool your turbo quicker and maintain tight control of boost levels throughout your power curve. In addition, our solenoid features a balanced valve to withstand up to 120psi without a slowing response by even a single millisecond.
Revolutionizing the Subaru boost solenoid market, we have created model specific install brackets that allow you to install our Boost Control Solenoid with a factory fit and finish. To top it all off, our solenoid also uses a Subaru wiring harness connector so that you can simply unplug your OEM solenoid and plug ours in. No more cutting and crimping OEM wires together!
The solenoid itself is one of a kind. MAC manufactures pneumatic control products for the largest commercial operations in the world, where every minute of downtime can cost tens of thousands of dollars, so we worked closely with their engineers to design this unique valve, incorporating proprietary features, exclusive to GrimmSpeed, that make our solenoid the toughest on the market. Those features include special seals to protect it from moisture and high temp coils to keep response times at 6 milliseconds or less, even in extreme heat. We have worked with many of the top tuners in the country to ensure that our solenoid works safely with the factory Subaru ECU.

Our special solenoid features, combined with our factory-fit brackets, ensure that this complete boost control solution will withstand the harsh heat and vibration of your engine bay. The Subaru harness connectors that we use include weatherproof terminal seals, carefully crimped with DELPHI equipment by our expert assembly staff. Mounting brackets are laser cut and then black zinc plated to ensure corrosion resistance. Each bracket has threaded PEM nuts pressed in for a solid connection with no risk of stripping threads. Each low profile 1/8" NPT nickel plated fitting is installed in the proper orientation using a 120psi thread sealant for a clean, compact, robust installation.

You don't need to take our word for it, trust your tuner When it comes to boost control systems, be sure to consult with your tuner to ensure that you're building a setup that they're confident tuning. The good news is that with well over 25,000 units in use on some of the fastest Subarus in the world, with the GrimmSpeed Boost Control Solenoid, you'll be in great company. As with any change to your boost control system, upgrading to a 3-port solenoid does require tuning.

"The GS 3-port BCS provides rapid boost response while maintaining the ability to make acute adjustments via turbo dynamics. While many other boost control solenoids react to adjustments too fast which can make them difficult to control with as much finesse as the stock bleed system. This solenoid can make micro-adjustments at the edge of target boost not only providing better spool, but overall more control." - AWD Tuning
"The GrimmSpeed™ BCS is a compact, well designed unit. Its design as a 3-port solenoid provides better boost control then the stock bleed-type style. Often, this enables a tuner to cut mapped wastegate duty cycles in half. This change in WGDC gives a tuner more granularity when tuning, and can yield much improved boost curves. In addition, the 3-port design often significantly improves spool." - Bullwinkle Tuning
Overall rating: 4.972973 / 5 from 37 reviews.
The GrimmSpeed 3-Port Electronic Boost Control Solenoid offers quick and easy installation, superior boost control, and amazing throttle response for Subaru STIs from 2008-21. It provides precise boost adjustments and enhances vehicle performance.
Review topics: ["quality","replacement","power","install","customer service","issues","car","boost","tuner","ebcs","spool","comes","grimmspeed","mod"].
"When I received it I was beyond excited to start working on my car again and it was a straight forward job."
"Probably easier than changing your oil, super fast the hardest part of the install was getting the the tube onto the turbo barb but over all a 10-15 min job!"
"Everywhere I looked for info on boost control said that the GS 3 port is one of the best ways to go and sure enough my tuner even said that it was a wise choice especially if I’m planning on moving to an EWG setup but for now this little solenoid helped me put down some decent numbers for my supporting mods. Thank GS you guys are awesome and provide top notch parts"
"This product was easy to install and the quality is great"
"One of the best ebcs around! My tuner recommended me to get this product before i go in for stage 2 tuning."
"Great product by GS, was easy to install and was highly recommended by my tuner."
"Docked one star due to lack of instructions for STI vacuum hose configuration in the official GS install video. Other than that, tuner said boost was controlled perfectly with my Catless GS DP matted to a perrin CBE and intake with a Cobb protune. No over boosting for this guy!"
"Easy installation works great for tuning the Subaru"
"...and like before, perfect. I am sold on this EBCS in so many ways. The install is super easy and the boost stays consistent. I would not use any other EBCS, period. Thanks again"
"Great response, coming from using the oem boost control this one feels more responsive, boost comes on a lot quicker and my tuner was able to really dial in my car. It feels great now!"