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COBB V3 Air / Oil Separator (AOS) 2002-2007 WRX / 2004-2007 STI

SKU 811615
Save $54.08 Save $54.08
Original price $520.00
Original price $520.00 - Original price $520.00
Original price $520.00
Current price $465.92
$465.92 - $465.92
Current price $465.92
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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 EJ 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 2 reviews
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R
R.L.
Cool

Used the IAG instructions and a youtube video to install. Not too bad of an install

Ronil,

Thank you for sharing your 5 Star Review and experience with the COBB V3 Air / Oil Separator! We are glad to hear that you found the installation process manageable with the help of other instructions and a YouTube video. We appreciate your feedback and hope you continue to enjoy your AOS!

Regards,

J
Jacob Bivens
Poor directions missing parts

The app used for the directions is really really bad. If I didn’t have the 3MI racing turbo Y return line I would be shorted in hose. You should not be shorted fittings or hose for the premium you pay. Ridiculous. Plan on it taking up more money than what it costs for the can.

Jacob,

Thank you for your review. COBB provides written installation directions directly on their website. I have attached a link below. If these directions are followed properly, no extra material is needed. Also, the Subimods Team is always available if you have installation questions.

https://cobbtuning.atlassian.net/wiki/spaces/PRS/pages/1435893875/811615+822615+-+Air+Oil+Separator+WRX+2004+-+2014+STI+04-20

Regards,

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