The IAG Performance Street Series billet aluminum air/oil separator (AOS) vents crankcase gasses back to the turbo inlet. The design is based on years of service on racing and high horsepower Subaru's. The AOS's approximate 1-liter capacity, fully heated housing, superior breathing and unique patent pending baffle design sets it apart from the rest.
The most popular Subaru AOS is now even better! The IAG AOS body is completely redesigned using cast aluminum and features an integrated coolant passage for better heat retention. Additionally, the V3 AOS heating system is upgraded by relocating the coolant lines to the bottom of the body using new swivel fittings, heat sleeving and an integrated coolant bleeder. These heating system upgrades will allow for a cleaner installation and less condensation buildup in colder climates. The new compact body has the same 1-liter capacity as V2, but features a sleeker design and adds removable ORB fittings for greater versatility.
Fits all 2008-2014 Subaru WRX and 2008-2021 WRX STI.