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Precision Boost Control Built for the STI's Engine Bay Layout
The GrimmSpeed 3-Port Electronic Boost Control Solenoid (Version 2) delivers the same reliable 3-port design as its sibling part, rated to 120psi, but ships with a mounting bracket engineered specifically for the STI and Forester XT engine bay layout. It connects using the OEM Subaru-style wiring harness connector, so there's no need to splice wires or fabricate a mount. This is the correct version for the vehicles listed in the fitment table below.
Key Features
- 3-port electronic design for precise boost pressure control
- Rated up to 120psi
- Plug-and-play OEM Subaru-style wiring connector
- STI/Forester XT-specific mounting bracket included
- Direct replacement for the factory-style boost control solenoid
Fitment
| Year Range | Make | Model | Trim |
|---|---|---|---|
| 2008-2017 | Subaru | STI | |
| 2009-2013 | Subaru | Forester | XT |
Specifications
| Detail | Value |
|---|---|
| Brand | GrimmSpeed |
| Part Number | GRM405326 |
| Type | 3-Port Electronic Boost Control Solenoid (V2) |
| Pressure Rating | 120 psi |
| Connector | OEM Subaru-style plug-and-play |
| Mounting | STI/Forester XT-specific bracket included |
What's Included
- GrimmSpeed 3-port boost control solenoid
- STI/Forester XT 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.
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FAQ
What is the GrimmSpeed 405326 boost control solenoid?It's a 3-port electronic boost control solenoid rated to 120psi with a mounting bracket designed specifically for the STI and Forester XT, using a plug-and-play OEM-style connector.
Which vehicles fit the GRM405326?This version fits 2008-2017 Subaru STI and 2009-2013 Subaru Forester XT.
How is this different from the WRX version?The internal solenoid is the same 3-port design, but this version includes a different mounting bracket shaped for the STI/Forester XT engine bay.
Do I need to modify factory wiring?No, it connects using the OEM Subaru-style connector for a plug-and-play install.
Can I use this with a standalone engine management system?Yes, the 3-port design works with most standalone boost controllers as well as factory ECU-controlled boost solenoid outputs.
Is a mounting bracket included?Yes, a bracket specific to the STI and Forester XT mounting location is included.
What is the maximum pressure rating?The solenoid is rated up to 120psi.
Will this fit a WRX instead of an STI?No, WRX and Legacy GT applications use the GRM405322 version with a different bracket.
Install Instructions
- Disconnect the negative battery terminal before beginning work
- Locate and unplug the factory boost control solenoid
- Remove the factory solenoid and its mounting bracket
- Install the GrimmSpeed STI/Forester XT mounting bracket in the factory location
- Mount the new 3-port solenoid onto the bracket
- Connect the 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
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