Take Manual Command of Boost Response Without Wiring Guesswork
The GrimmSpeed 3-Port Electronic Boost Control Solenoid replaces the factory boost solenoid with a proven 3-port design rated to 120psi, giving your engine management or standalone boost controller precise control over wastegate duty cycle. It connects to the OEM Subaru-style wiring harness connector for a plug-and-play install, and it comes with a model-specific mounting bracket so there’s no need to improvise with zip ties. This version is built for the WRX, Legacy GT, and Forester XT platforms listed below.
Key Features
- 3-port design allows precise electronic control of boost pressure
- Rated up to 120psi for aggressive boost control applications
- Plug-and-play OEM Subaru-style wiring harness connector
- Model-specific mounting bracket included, no zip ties required
- Direct upgrade over the failure-prone factory boost control solenoid
Fitment
| Year Range | Make | Model | Trim |
|---|---|---|---|
| 2008-2014 | Subaru | WRX | |
| 2005-2009 | Subaru | Legacy | GT |
| 2009-2013 | Subaru | Forester | XT |
Specifications
| Detail | Value |
|---|---|
| Brand | GrimmSpeed |
| Part Number | GRM405322 |
| Type | 3-Port Electronic Boost Control Solenoid |
| Pressure Rating | 120 psi |
| Connector | OEM Subaru-style plug-and-play |
| Mounting | Model-specific bracket included |
What’s Included
- GrimmSpeed 3-port boost control solenoid
- Model-specific mounting bracket
- Mounting hardware
About GrimmSpeed
GrimmSpeed designs and manufactures performance parts specifically engineered around Subaru platforms, with a focus on bolt-on solutions that work with the factory ECU and wiring.
FAQ
What is the GrimmSpeed 405322 boost control solenoid?
It’s a 3-port electronic boost control solenoid rated to 120psi that replaces the factory unit on the WRX, Legacy GT, and Forester XT, using a plug-and-play OEM-style connector and a model-specific mounting bracket.
Which vehicles fit the GRM405322?
This version fits 2008-2014 Subaru WRX, 2005-2009 Subaru Legacy GT, and 2009-2013 Subaru Forester XT.
Do I need to modify the factory wiring harness?
No, this solenoid uses an OEM Subaru-style connector for a plug-and-play electrical connection.
Is a mounting bracket included?
Yes, a model-specific mounting bracket is included so the solenoid mounts securely without zip ties.
Will this work with a standalone boost controller?
Yes, the 3-port design is compatible with most standalone electronic boost controllers as well as ECU-controlled boost solenoid outputs.
What’s the maximum pressure rating?
The solenoid is rated up to 120psi.
Do I need the STI-specific version instead?
No, this GRM405322 version is designed for WRX, Legacy GT, and Forester XT applications. STI and later Forester XT use the GRM405326 version with a different bracket.
Does this replace the factory boost solenoid entirely?
Yes, it is a direct replacement for the factory electronic boost control solenoid on supported platforms.
Install Instructions
- Locate the factory boost control solenoid in the engine bay
- Disconnect the negative battery terminal before beginning work
- Unplug the factory electrical connector and remove the factory solenoid and bracket
- Install the GrimmSpeed model-specific mounting bracket in the factory location
- Mount the new 3-port solenoid to the bracket
- Connect the factory OEM-style connector to the new solenoid
- Reconnect the vacuum and pressure lines to the correct ports
- Reconnect the battery and verify boost control operation with a scan tool or boost gauge
