"Haven't install but look very well crafted"
The Original Direct-Fit BCS for turbo Subarus.
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.
QUICK SPECS:
- Decrease Spool Time - flows 10% more than the competition
- Plug and Play into OEM Harness - no splicing wires like other BCS solutions
- Works Safely with Factory Subaru ECU - custom coil to match ECU voltage
- Nickel Plated Fittings - not the easily breakable plastic fittings!
- 15min Installation - extremely simple with our written and video guides
DESIGN:
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.

MATERIALS:
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.

TRUST YOUR TUNER:
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
FITMENTS:
- 2004-07 Subaru STI
- 2006-07 Subaru WRX
- 2004-08 Subaru Forester XT
- 2004-06 Subaru Baja XT
INSTALL GUIDE:
Boost Controller Install Instructions - SubaruOverall rating: 5.0 / 5 from 34 reviews.
AI Generated Review Summary
The GrimmSpeed 3-Port Electronic Boost Control Solenoid offers easy installation, exceptional boost response, and precise control for turbo Subarus. It features a balanced valve for high-pressure tolerance and a factory-fit design. Users praise its quick spool time and compatibility with Subaru ECUs.
Summary topics
- Ease of Installation: 26%
- Boost Response: 17%
- Boost Control: 33%
Review topics: ["customer service","power","replacement","install","issues","car","boost","grimmspeed","tuner","mod","comes","spool","ebcs"].
Review highlights
- "Quick and easy install, very precise boost control (with a professional tune), and excellent customer service." —
- "The install is super easy and the boost stays consistent." —
- "Highly recommend for anyone needing a replacement or just wants quicker response from their vehicle." —
Reviews
Arrived busted, GREAT customer Service -> Now runnin like a CHAMP
"This was something I struggled with a bit as I couldn't figure out if I made an installation error, but it turned out a wire was busted, and that was why the solenoid wasn't working (makes sense). To make matters worse, my hawkeye (06) didn't have the same install fittings present called for in the instructions. The team at GS rushed a replacement out to me, and now that I have secured the knock sensor (facepalm) and a new tune, my boost control is SO MUCH BETTER. The tuner kept saying how good the GS 3 ports are, and it must be true. Easy install once I decided how to mount it."
Quality!
"Sturdy quality build materials."
Boost controller
"Awesome! Really helped me reach my goals."
Buy with confidence.
"Kudos to a great product backed by an equally good if not better service. Last purchase i got was a set of ported/coated headers, cross over pipes and uppipe close to 5 years ago. Am surprised that their commitment to excellent service is still top notch."
2nd one I have bought and installed.
"...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"
EBCS - Awesome!
"Got the EBCS very quickly from GS, install was easy, car made 300 easy with steady and precise boost control!"
Great!
"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!"
Absolutely amazing product.
"Recently purchased this 3 port ebcs to replace my stock one that malfunctioned on my 05 LGT. It absolutely blew my mind away how much it opened up the entire system and advanced throttle response. Highly recommend for anyone needing a replacement or just wants quicker response from their vehicle."
Easy installation, greatly reduces turbo lag
"2004 wrx, stage 1 (Cobb v3) on 93 octane. Installed this EBCS and got a pro-tune. The car is finally pulling as hard as I want it to be. I may go stage 2, but for now I am very happy with the results."