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COBB V3 Air / Oil Separator (AOS) 2015-2021 WRX

SKU 843615
Save $58.24 Save $58.24
Original price $560.00
Original price $560.00 - Original price $560.00
Original price $560.00
Current price $501.76
$501.76 - $501.76
Current price $501.76

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.

  • 1 Liter Holding Capacity
  • Integrated ORB Ports
  • Compact Cast Aluminum Body w/ Black Powdercoat Finish
  • 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. The bottom of the AOS is shaped like a snail, redirecting positive crank pressure into the same swirl pattern produced by the 3 side ports. Allowing maximum oil drainage while separating oil from the air in all the venting ports. The back plate of the AOS features a unique coolant routing system that heats the entire AOS to the same temperature of the engine. This maximizes the evaporation of any water collecting inside of the can. The hotter the AOS, the less water will collect inside and mix with the oil.

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.

Customer Reviews

Based on 4 reviews
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N
Nic babb
as advertised

no issues and as advertised!

Nic,

Thank you for taking the time to leave a 5 Star Review of the COBB V3 AOS! Definitely a must have for your WRX! Enjoy!

Regards,

C
Christian Seitz
Best Aos on the market

Definitely I would recommend this the cobb Air/oil seperator to anyone I did a full tear down before installing to get a Better picture of how it works so inside are uniquely designed baffles litterly and it's super complex but yet super simple on how it functions what is freaking awesome is how each baffle is on a slight inclination starting from the bottom to the top and it has tiny ports on the inside that allow the air and oil to be separated I think it has something to do with the density of the oil but anyways yess I would definitely recommend the cobb Aos and I would 110% recommend ordering from subimods due to the consumer friendly staff and shipping time

Christian,

Thank you for your 5-star review of the COBB V3 Air/Oil Separator! I am glad to hear that you found it to be the best on the market and that you were impressed with its unique design and effectiveness in separating air and oil. COBB partnered with IAG to design this AOS with some extra perks such as a Coolant Bleeder Valve, Integrated ORB Ports, and Laser Etched COBB Logo! It is great to know that you had a positive experience ordering from Subimods and that our team provided excellent customer service! Thank you for your recommendation, and we hope you continue to enjoy your COBB AOS!

Regards,

S
Stephen Burt
Excellent

Amazing!!!

Stephen,

Adding and AOS is absolutely a number 1 modification and COBB has done an awesome job with their V3 AOS! Thank you for the 5 Star Review!

Regards,

C
Chris
Cobb AOS

This does all the things. Your first gear becomes extremely functional. Starts and idles are super smooth. You will not use one of the ports unless you have an STI. Install isn't terrible. Last version was all black, new version has the red anodized top. You will not receive the condensation covers, Cobb doesn't use them anymore. This will extend the life of your engine big time.

Chris,

Thank you for the 5 Star Review! The COBB V3 AOS does exactly as you say and will extend the life of your engine! It ultimately helps to prevent oil vapors from being introduced into the intake system. This is important because 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.

Regards,

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