Radium AOS-R Air Oil Separator-Return Kit, Subaru WRX (2008-2014) / STI (2015-2021) / Forester XT (2009-2013)

The Radium Engineering 20-0607 AOS-R (Air Oil Separator-Return) Kit suits the 2008–2014 Subaru WRX, 2015–2021 WRX STI and 2009–2013 Forester XT. High-powered, modified Subaru engines generate excessive blow-by that can quickly fill an ordinary small catch can. The AOS-R keeps blow-by oil and pollutants out of the intake pipe, manifold, turbocharger and intercooler at all engine loads — and returns what it collects to the oil pan, so no servicing is required.

A built-in heater stops water condensing inside the unit, and an integrated water trap around the bottom perimeter of the can keeps water from descending into the oil pan.

Key Features

• Oil return to sump — no emptying or servicing required
• Built-in heater — prevents water condensing in the separator
• Integrated water trap — keeps water out of the oil pan
• All-load protection — keeps oil out of the intake, turbo and intercooler

Benefits

• Effectively raises octane and improves performance with cleaner inlet air
• Prevents oil build-up in the intake, intercooler, throttle body and intake manifold
• Lowers hydrocarbon emissions

Vehicle Fitment

• 2008–2014 Subaru WRX (GR/GV)
• 2015–2021 Subaru WRX STI (VA)
• 2009–2013 Subaru Forester XT (SH)

Available Part Numbers

• 20-0607 — AOS-R Kit, 08–14 WRX / 15–21 STI / 09–13 Forester XT

Why Radium Engineering?

• ✔ Designed and manufactured in the USA
• ✔ CNC machined billet aluminium — precision fit, no compromise
• ✔ Trusted by professional motorsport teams and serious enthusiasts worldwide
• ✔ Exclusively distributed in Australia by Coore

Genuine Radium Engineering product, supplied by Coore Australia. Recommended for high-output modified engines. Professional installation recommended.

Browse more Radium Engineering parts at JDM Mods NQ