GrimmSpeed Air Oil Separator Blue WRX (2002-2007) STI (2004-2018) Mazda which relocates the air filter

which relocates the air filter outside of the engine bay for a cooler

If you're installing a smaller supercharger pulley you will need a smaller belt to reduce the slack and allow the belt tensioner to work properly

and it can be installed with your stock exhaust or with a Milltek Sport unit (or any other aftermarket unit for that matter)

the Supersonic for the Subaru WRX/STI is sure to turn heads wherever you are

and spare "C" clip

GrimmSpeed Air Oil Separator Blue WRX (2002-2007) STI (2004-2018) Mazda which relocates the air filterGrimmSpeed has a unique design for the Subaru WRX, STI and Legacy GT which allows you to keep your PCV valve while separating the oil out of the crankcase and head ventilation air. None of the other competitors on the market are able to vent both. The unit is very compact and efficient, it bolts directly on to the factory oil cap location. You will no longer have to keep tabs on your oil level and or empty the catch can like on most standard cans as