This EJ205 also has the AVCS choice to run For added overall performance. To operate the AVCS, the avcs harness and the avcs ecu is necessary. Nevertheless, This can be optional, you don’t really have to run the avcs to create the motor in shape within your 2002 to 2005 WRX. It is a direct extensive block alternative for 2002 to 2005 Subaru WRX.I