PERRIN has just announced the release of its Air Oil Separators for WRX/STI applications. These Performance Air Oil Separators trap oil from the crankcase vents before it enters the intake, thus increasing intercooler efficiency and reducing chances of performance-robbing detonation. Application-specific mounting brackets make this kit easy to install and includes all hardware necessary.

The AOS increases intercooler efficiency by reducing the amount of oil deposited into your intercooler and intake system! As blow-by/oil builds up inside your intercooler, the less efficient it becomes due to less heat being transferred away from your engine. This leads to power loss and detonation, which can be damaging to your engine.

Reduce carbon build up in the combustion chamber, intake valves, and in your intake tract. Crankcase blow-by is recirculated back to the intake to be ingested by the engine, but in doing so, gets stuck in the intake tract, intake valves, and the intercooler. This builds up over time which causes a loss in power and extra wear and tears on your valve train.

Over the years, a slight buildup may occur inside your AOS. This can be quickly taken care of by removing one bolt to access the inside for cleaning.