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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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    70 Results

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

    IAG-ENG-7185BK

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

    5.0(7)
    $499.99
    IAG Performance Air Oil Separator AOS - Red - 2008-2014 WRX / 2008-2021 STI / 2005-2009 Legacy GT

    IAG-ENG-7186RD

    IAG Performance Air Oil Separator AOS - Red - 2008-2014 WRX / 2008-2021 STI / 2005-2009 Legacy GT

    5.0(1)
    $499.99
    GrimmSpeed Air Oil Separator Red - 2002-2007 Subaru WRX / 2004-2021 STI

    19 In Stock

    078006R

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

    5.0(1)
    $315.00
    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
    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)
    $486.20
    02-07 WRX / 04-21 STI GrimmSpeed Air Oil Separator

    15 In Stock

    078006

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

    $315.00
    COBB Tuning Air Oil Separator Black/Red - Subaru Models (inc. 2008-2020 STI / 2008-2014 WRX)

    6 In Stock

    822615

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

    4.5(2)
    $595.00
    08-14 WRX / 05-12 Legacy GT GrimmSpeed Air Oil Separator

    16 In Stock

    078016

    08-14 WRX / 05-12 Legacy GT GrimmSpeed Air Oil Separator

    $315.00
    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)
    $89.99
    IAG AOS Pitch Mount Bracket - Subaru Models (inc. 2004-2007 STI / 2006-2007 WRX)

    1 In Stock

    IAG-ENG-7802

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

    4.0(1)
    $69.99
    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 Air Oil Separator Street to Competition Series Conversion Kit - Subaru Models (inc. 2004-2021 STI / 2006-2014 WRX)

    IAG-ENG-7210

    IAG Air Oil Separator Street to Competition Series Conversion Kit - Subaru Models (inc. 2004-2021 STI / 2006-2014 WRX)

    $89.99
    IAG Performance Air Oil Separator AOS - Neon Yellow - 2015-2021 Subaru WRX / 2014-2018 Forester XT

    IAG-ENG-7187NY

    IAG Performance Air Oil Separator AOS - Neon Yellow - 2015-2021 Subaru WRX / 2014-2018 Forester XT

    $499.99
    IAG Performance Air Oil Separator AOS - Black - 2015-2021 Subaru WRX / 2014-2018 Forester XT

    2 In Stock

    IAG-ENG-7187BK

    IAG Performance Air Oil Separator AOS - Black - 2015-2021 Subaru WRX / 2014-2018 Forester XT

    $499.99
    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
    IAG Performance Air Oil Separator AOS - Black - 2008-2014 WRX / 2008-2021 STI / 2005-2009 Legacy GT

    IAG-ENG-7186BK

    IAG Performance Air Oil Separator AOS - Black - 2008-2014 WRX / 2008-2021 STI / 2005-2009 Legacy GT

    $499.99
    IAG Performance Air Oil Separator AOS - Red - 2015-2021 Subaru WRX / 2014-2018 Forester XT

    IAG-ENG-7187RD

    IAG Performance Air Oil Separator AOS - Red - 2015-2021 Subaru WRX / 2014-2018 Forester XT

    $499.99
    Radium AOS-R Kit - Subaru Models (inc. 2008-2014 WRX / 2008-2021 STI / 2009-2013 Forester XT)

    1 In Stock

    20-0607

    Radium AOS-R Kit - Subaru Models (inc. 2008-2014 WRX / 2008-2021 STI / 2009-2013 Forester XT)

    $427.45
    IAG Performance Air Oil Separator AOS - Neon Yellow - 2008-2014 WRX / 2008-2021 STI / 2005-2009 Legacy GT

    IAG-ENG-7186NY

    IAG Performance Air Oil Separator AOS - Neon Yellow - 2008-2014 WRX / 2008-2021 STI / 2005-2009 Legacy GT

    $499.99

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