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IAG Performance

IAG Performance - Subaru 08-14 WRX / 08-21 STI - V3 Competition Series Air / Oil Separator (Black)

IAG Performance - Subaru 08-14 WRX / 08-21 STI - V3 Competition Series Air / Oil Separator (Black)


Regular price $419.99 USD
Regular price Sale price $419.99 USD
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This is the IAH Performance V3 Competition Series Air / Oil Separator. Competition Series AOS is “Competition Only” components for installation exclusively on “Competition” vehicles or “Racing” vehicles not subject to pollution control.

IAG recommends the Competition Series AOS for Competition vehicles with greater than 600 WHP output. With that being said this AOS system fights hard for your engine by preventing harmful oil and vapors from harming the performance of your vehicle under high-performance and competitive driving conditions. 





  • Keeping oil out of the engine intake tract is extremely important in preventing premature mechanical failure and maintaining performance
  • Prevents oil from coating the internal portions of the intake, intercooler, and piping
  • Prevents premature failure of the rubber or silicone hoses, which can lead to failed connections
  • Once the oil reaches the intake tract it will directly enter the intake manifold and then the combustion chamber of the engine
  • Oil inside of the combustion chamber can cause detonation and preignition, high emissions, smoke, loss of power, decreased gas mileage, and even catastrophic engine failure leading to expensive repair bills



  • The Competition Series vents the PCV gases to the atmosphere via a large 1” diameter vent hose
  • All oil in the CCV systems is prevented from entering the intake tract. IAG’s V3 AOS also eliminates the OEM PCV valve which is known to fail in high horsepower applications



  • The IAG AOS body is completely redesigned using cast aluminum and features an integrated coolant passage for better heat retention
  • The V3 AOS heating system is upgraded by relocating the coolant lines to the bottom of the body using new swivel fittings, heat sleeving, and an integrated coolant bleeder
  • These heating system upgrades will allow for a cleaner installation and less condensation buildup in colder climates
  • The new compact body has the same 1-liter capacity as V2, but features a sleeker design and adds removable ORB fittings for greater versatility



  • True 360 Degree Rotating Breather Port
  • Dual Breather Ports
  • Greater Pressure Stream Oil Separation
  • As air and particles of oil enter into the AOS, the largest particles of oil will collect on the inner surface of the can and drain to the bottom, but the smallest particles will remain suspended in the pressurized stream
  • As the air makes its way through the multi-stage baffle system, gravity pulls oil from the air
  • By increasing the overall volume of the breather opening on the top of the AOS, IAG has drastically decreased the exit velocity of the crankcase vent (CCV) stream
  • The slower velocity leads to greater oil separation from the pressure stream
  • A total of 20 mounting holes enable the breathing port a full 360° of rotation
  • On the top, a thick Viton o-ring seals the can. Every o-ring in our AOS is formed from Viton which offers superior temperature and chemical resistance



  • Compact Cast Aluminum Design
  • Approximate 1 Liter Holding Capacity
  • Integrated ORB Ports
  • Aluminum Body is powder-coated in Red or Black Wrinkle Finish
  • The side of the AOS features 3 -8 ORB removable billet hose barbs
  • Each engine vent port receives its own connection to the AOS
  • By giving each engine port its own entrance to the AOS IAG has allowed for more effective and faster excavation of crankcase pressure
  • Reduces the overall system pressure



  • Unique Baffling Controls Crankcase Pressure
  • Returns Oil To The Engine
  • No Maintenance or Manual Draining Required
  • 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
  • Allows maximum oil drainage, while separating oil from the air in all the venting ports



  • The AOS drain port is able to be rotated for ease of installation, as well as pre-threaded to accept an ORB fitting if desired



  • Includes all fitting required for installation
  • Includes unique billet aluminum coolant swivel fittings



  • The supplied coolant hose is built to SAE 30R9 standards
  • It will withstand coolant temperatures of +257°F
  • The oil vapor hose is designed to withstand oil and fuel vapors, exceeding SAE J30R7



  • Heated By Engine Coolant
  • Reduces Moisture & Oil Mixing
  • Features an integrated coolant chamber that heats the entire AOS to the same temperature as the engine
  • This cast aluminum can hold more heat which maximizes the evaporation of any condensation collecting inside of the can
  • The hotter the AOS, the less condensation will collect inside and mix with the oil



  • Multi-point adjustable mounting bracket
  • If your engine bay changes, you can easily change how and where you mount the AOS
  • The V3 AOS body features a greater number of mounting holes enabling a wider range of adjustments
  • A single, laser-cut, mounting bracket is included that fits nearly all applications and configurations
  • A laser-cut harness relocation bracket is also included that allows the engine harness connector to be moved forward for additional clearance



  • Ready To Install
  • Hardware, Lines & Fittings Included
  • The AOS arrives completely assembled and ready for immediate installation. However, the entire unit can be broken down for cleaning with a single Allen wrench, you can remove two bolts and the AOS easily separates into individual pieces


    NOTE: The Competition Series AOS may require additional tuning calibration - Please consult a tuner for more information.


    • Subaru 08-14 WRX
    • Subaru 08-21 STI


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