The COBB 3-Port Boost Control Solenoid (BCS) adds the flexibility and precision needed for properly controlling boost via the factory ECU. Many upgrades to the turbocharging system (such as larger turbochargers and external wastegates) require the increased performance, reliability, flexibility, safety and installation options that the COBB 3-Port BCS provides.
If you are running an external wastegate setup you will need the upgrade kit.
Note : This product requires custom tuning.
Fits 2002-2007 WRX and STI.