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    Air Oil Separators

    If you drive a Subaru, then it is common to see so many of them with some sort of aftermarket Air Oil Separator kit on it. The way the  stock PCV system on the Subaru works is that you have vents that come off the head, as well as the crankcase. These vents are routed to the turbo inlet, and even though inlet sucks in air, it can be common for oil to make its way into the inlet as well. Although this is somewhat a normal occurrence for a Subaru, burning oil can cause issues such as detonation, and it can effect the octane rating in your fuel. 

    Ar RallySport Direct, we carry a wide selection of Air oil Separators designed to filter the oil from the air, and drops the oil back into the oil pan so that only air gets back to the turbo inlet. You can choose one of Grimspeed's compact units that are mounted on the oil filler cap, or choose from other quality designs from Crawford, PERRIN, Beatrush and finally Moroso. 

    Now you can promote better longevity and a cleaner, healthier running engine with one of these fine products. And when you're ready to ready take control of your oiling system, choose a deeper oil pan  to increase the capacity, or get a catch can to catch any oil that overflows from your cranking system. 

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    63 Results

    Killer B Motorsport Air Oil Separator Complete Kit - 2002-2007 Subaru WRX / STI

    GD-MV3S-C

    Killer B Motorsport Air Oil Separator Complete Kit - 2002-2007 Subaru WRX / STI

    5.0(2)
    $505.48
    COBB Tuning Air Oil Separator Black/Red - Subaru Models (inc. 2008-2020 STI / 2008-2014 WRX)

    41 In Stock

    822615

    COBB Tuning Air Oil Separator Black/Red - Subaru Models (inc. 2008-2020 STI / 2008-2014 WRX)

    4.5(2)
    $595.00
    GrimmSpeed Air Oil Separator Red - 2002-2007 Subaru WRX / 2004-2021 STI

    14 In Stock

    078006R

    GrimmSpeed Air Oil Separator Red - 2002-2007 Subaru WRX / 2004-2021 STI

    5.0(1)
    $315.00
    IAG AOS Pitch Mount Bracket - Subaru Models (inc. 2004-2007 STI / 2006-2007 WRX)

    IAG-ENG-7802

    IAG AOS Pitch Mount Bracket - Subaru Models (inc. 2004-2007 STI / 2006-2007 WRX)

    4.0(1)
    $69.99
    PERRIN Air Oil Separator Red Stock TMIC - 2002-2007 Subaru WRX / STI

    3 In Stock

    PSP-ENG-605RD

    PERRIN Air Oil Separator Red Stock TMIC - 2002-2007 Subaru WRX / STI

    4.2(6)
    $622.13
    IAG Air Oil Separator Street to Competition Series Conversion Kit - 2015-2021 Subaru WRX

    IAG-ENG-7211

    IAG Air Oil Separator Street to Competition Series Conversion Kit - 2015-2021 Subaru WRX

    4.0(1)
    $114.70
    Killer B Motorsport Air Oil Separator - 2008-2014 Subaru WRX / 2015-2021 STI / 2005-2009 Legacy GT

    GR-MV3S-C

    Killer B Motorsport Air Oil Separator - 2008-2014 Subaru WRX / 2015-2021 STI / 2005-2009 Legacy GT

    3.0(1)
    $505.00
    Verus Engineering Air Oil Separator Automatic Drainback Kit - 2013-2021 Scion FR-S / Subaru BRZ / Toyota 86

    A0010A

    Verus Engineering Air Oil Separator Automatic Drainback Kit - 2013-2021 Scion FR-S / Subaru BRZ / Toyota 86

    2.0(1)
    $49.95
    IAG Performance V4 Air Oil Separator AOS - Red - 2004-2007 Subaru STI / 2006-2007 WRX

    1 In Stock

    IAG-ENG-7185RD

    IAG Performance V4 Air Oil Separator AOS - Red - 2004-2007 Subaru STI / 2006-2007 WRX

    $499.99
    PERRIN Air Oil Separator Neon Yellow - Subaru Models (inc. 2008-2014 WRX)

    PSP-ENG-606NY

    PERRIN Air Oil Separator Neon Yellow - Subaru Models (inc. 2008-2014 WRX)

    $622.13
    Killer B Motorsport Air Oil Separator Barebones Kit - 2002-2007 Subaru WRX / STI

    GD-MV3S-B

    Killer B Motorsport Air Oil Separator Barebones Kit - 2002-2007 Subaru WRX / STI

    $359.00
    IAG V2 AOS Coolant Line 43 in - Universal

    2 In Stock

    IAG-ENG-7000-CL43

    IAG V2 AOS Coolant Line 43 in - Universal

    $32.99
    Radium Air Oil Separator Return Kit (AOS-R Kit) - 2013-2016 Scion FR-S / 2013-2020 Subaru BRZ / 2017-2020 Toyota 86

    3 In Stock

    20-0351

    Radium Air Oil Separator Return Kit (AOS-R Kit) - 2013-2016 Scion FR-S / 2013-2020 Subaru BRZ / 2017-2020 Toyota 86

    $427.45
    COBB Tuning Air Oil Separator Black/Red - 2002-2007 Subaru WRX / 2004-2007 STI

    14 In Stock

    811615

    COBB Tuning Air Oil Separator Black/Red - 2002-2007 Subaru WRX / 2004-2007 STI

    $565.00
    COBB Tuning Air Oil Separator Black/Red - 2015-2021 Subaru WRX

    20 In Stock

    843615

    COBB Tuning Air Oil Separator Black/Red - 2015-2021 Subaru WRX

    $610.00
    02-07 WRX / 04-21 STI GrimmSpeed Air Oil Separator

    8 In Stock

    078006

    02-07 WRX / 04-21 STI GrimmSpeed Air Oil Separator

    $315.00
    AOS Kit- GV/GR Subaru STI Red 2008-2014 Subaru WRX / STI

    A0259A-RED

    AOS Kit- GV/GR Subaru STI Red 2008-2014 Subaru WRX / STI

    $369.95
    IAG Performance V4 Air Oil Separator AOS - Neon Yellow - 2022-2024 Subaru WRX

    1 In Stock

    IAG-ENG-7188NY

    IAG Performance V4 Air Oil Separator AOS - Neon Yellow - 2022-2024 Subaru WRX

    $637.27
    IAG AOS Strut Tower Mounting Bracket for Rotated Turbo Kits - Subaru Models (inc. 2004-2007 STI / 2006-2007 WRX)

    1 In Stock

    IAG-ENG-7800

    IAG AOS Strut Tower Mounting Bracket for Rotated Turbo Kits - Subaru Models (inc. 2004-2007 STI / 2006-2007 WRX)

    $39.99
    IAG Performance V4 Air Oil Separator AOS - Neon Yellow - 2004-2007 Subaru STI / 2006-2007 WRX

    IAG-ENG-7185NY

    IAG Performance V4 Air Oil Separator AOS - Neon Yellow - 2004-2007 Subaru STI / 2006-2007 WRX

    $499.99

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    PERRIN Master Cylinder Brace Red - Subaru Models (inc. 2008-2014 WRX)

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    IAG Power Steering Line OEM Routing - 2002-2007 Subaru WRX / STI

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    CSF OEM Replacement Radiator - Subaru Models (inc. 2008-2014 WRX / 2005-2009 Outback / Legacy)

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    CSF OEM Replacement Radiator - Subaru Models (inc. 2008-2014 WRX / 2005-2009 Outback / Legacy)

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