Grimmspeed 3-Port Electronic Boost Control Solenoid 2015-2021 WRX

For Subaru enthusiasts, a 3-port Electronic Boost Control Solenoid (EBCS) is widely recognized as a “must-have” upgrade before tuning. GrimmSpeed has earned its reputation as the trusted brand in EBCS, with tens of thousands of solenoids in use worldwide.

The 2015–2021 WRX introduces a unique challenge: the factory 2-port solenoid mounts directly to the plastic turbo inlet and interfaces via an O-ring feature rather than a vacuum hose. GrimmSpeed leveraged this design and its proven expertise to create a high-performance, plug-and-play solution for precise boost control.

Quick Specs:

• Custom Machined Adapter – Uses the factory inlet port and is sealed with a VITON O-ring
• Black Anodized Finish – Corrosion-resistant in harsh engine bay environments
• 1/4" Barbed Fittings – Zinc plated, matching factory turbo and included hoses
• 3-Port Solenoid – Proprietary internal modifications for extreme automotive conditions
• Custom Wiring Connector – Plugs directly into the OEM harness with no modifications
• Compact Design – Mounts directly in the factory location with included zinc-plated steel bracket

The 3-Port Advantage:

Compared to the factory 2-port system, a 3-port EBCS allows your tuner to:

• Redirect boost signal back into the turbo inlet rather than venting to the atmosphere
• Maintain precise boost control throughout the power curve
• Improve tuning efficiency while keeping the factory MAF calibration consistent

The result: tighter, safer, and more consistent boost, making tuning easier and more reliable.

Design & Engineering:

• CAD-verified fitment for a perfect match to the factory turbo inlet
• Machined adapter recreates the OEM O-ring sealing feature
• 1/8" NPT threads allow barbed or AN fittings for use with the GrimmSpeed EBCS, Manual Boost Controller, or other boost solutions
• Compact mounting bracket secures the solenoid while maintaining flexibility for future upgrades
• OEM-style wiring connector ensures a true plug-and-play installation

Tuning Notes:

• Consult your tuner immediately after installation.
• Do not drive the vehicle under boost without proper tuning.

Fitment:

• 2015–2021 Subaru WRX (factory composite turbo inlet or upgraded GrimmSpeed Aluminum Inlet)

Installation Guide