
Description
The COBB Air/Oil Separator is placed within your Subarus crankcase ventilation system and helps to prevent oil vapors from being introduced into the intake system. The COBB Air Oil Separator has been developed in partnership with IAG Performance and offers exclusive features.
- Heat Shielding on Crankcase Breather and Oil Return Lines
- Coolant Bleeder Valve
- Bespoke COBB Color Combination
- Laser Etched COBB Logo
The Subaru FA engine has 3 ports that vent crank pressure: one on each cylinder head and another on the top of the block. Each engine vent port receives its own connection to the AOS. By giving each engine port its own entrance to the AOS we have allowed for more effective and faster excavation of crankcase pressure. Additionally, this reduces overall system pressure. With a 4" OD and 5.75" height, the AOS has an approximate 1 liter of holding capacity. The larger the AOS, the more power you can safely make without having to worry about the AOS overfilling.


Why?
The COBB Subaru Air/Oil Separator helps to prevent crankcase oil vapors from recirculating back through your engine's intake system.
Oil vapors passing through your engine's intake system lower the effective octane rating of fuel and can contribute to both oil and carbon buildup over time.
Features
Subaru Air/Oil Separator WRX 2015-2019
- Billet Aluminum Tank Design
- Bespoke COBB Anodizing on Caps
- Wrinkle Black Powder Coated Canister
- Laser Etched COBB Logo
- Developed in Partnership with IAG Performance
Customer Photos
Reviews
Subaru Air/Oil Separator WRX 2015-2019 is rated
out of
5 by
3.
Rated 5 out of
5
by
Jack Savage from
Love it!
I love this aos...top quality...instructions on website need to be rewritten as they can contradict themselves...especially for 2018+...lower side port gets capped instead of top, 5/8 hose with 90° was not needed, ecu bracket was not needed but I used it to hold ecu wires, also the connection under ac compressor is not a spring clamp...easier to unbolt compressor and remove the outer plastic connector instead of hose for better fitment...use die grinder or small belt sander (worked best for me)...other than that it is amazing and their customer support was amazing when I called to confirm!
Date published: 2018-12-23
Rated 4 out of
5
by
Canasian from
Great product, better explanation
Bought this a few days ago, self install fairly easy. Did the install in about 4.5 hours. The installation says for 2017-2018. But things definitely were different from a 2017 to a 2018 WRX. The ECU relocation bracket wasn't needed, brake lines did not need to be pryed for more space. And the breather fitting from the block definitely is different on a 2018.
Date published: 2018-04-06
Rated 4 out of
5
by
Tank from
Nice Solid Product!!
I love this Aos I bought it for my 2018 Wrx, Very easy to install
Date published: 2018-07-11
Questions
Confirmed Applications
2015 Subaru WRX Sedan CVT USDM
2015 Subaru WRX Sedan MT USDM
2016 Subaru WRX Sedan CVT USDM
2016 Subaru WRX Sedan MT USDM
2017 Subaru WRX Sedan CVT USDM
2017 Subaru WRX Sedan MT USDM
2018 Subaru WRX Sedan CVT USDM
2018 Subaru WRX Sedan MT USDM
2019 Subaru WRX Sedan CVT USDM
2019 Subaru WRX Sedan MT USDM