




Verus Engineering Air Oil Separator (AOS) - 2015-2021 Subaru WRX
OVERVIEW
The Verus Engineering Air Oil Separator (AOS) ensures the intake system remains oil-free. Oil in the intake system reduces octane, which can lead to detonation, reduction in power, and carbon build-up. The unit installs like an OE component with no change to the tune or setup needed. The Verus AOS also filters both the crankcase vent location as well as the intake filter location, through a single unit.
Four, 5 micron, coalescent filters, one on each inlet and outlet, baffling, and stainless mesh offer unprecedented air filtration for the crankcase air.
An optional coolant hook-up kit runs hot coolant through the AOS to reduce condensation build-up in colder months.
Anodized parts can potentially fade over time due to engine bay heat.
Note: Does not work with RHD models.
WHAT IS INCLUDED
- Assembled AOS
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- 4 Coalescent Filters
- Internal Baffling
- Stainless Mesh
- Sheet Steel Bracket for VA Chassis, LHD Only
- 3/4" Rubber Hose
- 1/2" Rubber Hose
- 3/8" Rubber Hose
- Hardware Bag, Including All Necessary Parts for a Seamless Install
PART NUMBER
A0323A-BLK
A0323A-BLU
A0323A-RED
Features:
- Prevents Oil from Getting in the Intake System, Reducing the Likelihood of Power Loss, Carbon Build-Up, or Detonation
- Superior Oil Separation Using 5-Micron Filters, Baffling, and Stainless Mesh
- Optional Cooling Kit, Catering to Your Specific Needs and Driving Environment
- Available in Three Bold Anodized Colors to Customize Your Subaru VA STI
Specifications:
- Air Oil Separator (AOS) Assembly: CNC Machined With Pride in Indianapolis, Indiana, from 6061-T6 Aluminum. Anodized in Your Choice of Three Colors (Red, Blue, and Black)
- Custom AOS Mounting Bracket: Made Specifically for the Left-Hand Drive Subaru VA STI
- Rubber Hoses: Cut to Length to Ensure a Seamless Installation Experience
- Stainless Hardware: Used Throughout and All Necessary Fittings for a Seamless Installation
Science:
Our AOS has one job, and that is to remove the oil from the engine crankcase system so the oil does not get into the intake system. Oil in the system reduces octane, which can lead to detonation, reduction in power, and carbon build-up.
Utilizing four 5-micron, coalescent filters, one on each inlet and outlet, baffling, and stainless mesh offers unprecedented air filtration for the crankcase air. These features ensure that you can push your vehicle to the limit, lap after lap.
Differences between an AOS and a Catch Can?
Here at Verus Engineering, we would almost always recommend our AOS system over a basic catch can. While catch cans are effective, there's nothing that comes close to a proper air-oil separator when looking for a set it and forget it option that is largely hands off.
Check out this video where RJ breaks down the key differences between a rudimentary catch can and a Verus Engineering AOS.
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