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GrimmSpeed Air Oil Separator - Subaru WRX 2002-2007 / STI 2004+
GrimmSpeed Air Oil Separator - Subaru WRX 2002-2007 / STI 2004+
GrimmSpeed Air Oil Separator - Subaru WRX 2002-2007 / STI 2004+
GrimmSpeed Air Oil Separator - Subaru WRX 2002-2007 / STI 2004+
GrimmSpeed Air Oil Separator - Subaru WRX 2002-2007 / STI 2004+
GrimmSpeed Air Oil Separator - Subaru WRX 2002-2007 / STI 2004+
Community Media
User Media for: GrimmSpeed Air Oil Separator - Subaru WRX 2002-2007 / STI 2004+
User Media for: GrimmSpeed Air Oil Separator - Subaru WRX 2002-2007 / STI 2004+
User Media for: GrimmSpeed Air Oil Separator - Subaru WRX 2002-2007 / STI 2004+
User Media for: GrimmSpeed Air Oil Separator - Subaru WRX 2002-2007 / STI 2004+
User Media for: GrimmSpeed Air Oil Separator - Subaru WRX 2002-2007 / STI 2004+
User Media for: GrimmSpeed Air Oil Separator - Subaru WRX 2002-2007 / STI 2004+
User Media for: GrimmSpeed Air Oil Separator - Subaru WRX 2002-2007 / STI 2004+
User Media for: GrimmSpeed Air Oil Separator - Subaru WRX 2002-2007 / STI 2004+
User Media for: GrimmSpeed Air Oil Separator - Subaru WRX 2002-2007 / STI 2004+
User Media for: GrimmSpeed Air Oil Separator - Subaru WRX 2002-2007 / STI 2004+
User Media for: GrimmSpeed Air Oil Separator - Subaru WRX 2002-2007 / STI 2004+
User Media for: GrimmSpeed Air Oil Separator - Subaru WRX 2002-2007 / STI 2004+
User Media for: GrimmSpeed Air Oil Separator - Subaru WRX 2002-2007 / STI 2004+
User Media for: GrimmSpeed Air Oil Separator - Subaru WRX 2002-2007 / STI 2004+

GrimmSpeed Air Oil Separator

Subaru WRX 2002-2007 / STI 2004+

$299.00

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Features & Product Details

RallySport Direct proudly carries a great selection of quality aftermarket performance products brought to you by GrimmSpeed. 

 

This is the GrimmSpeed Air Oil Separator. If you're familiar with modifying your vehicle, then you will know the importance of an air/oil separator, especially in a boxer-designed engine. The GrimmSpeed example comes with a unique design as it utilizes the factory oil filler cap location to maintain your PCV system while separating the harmful oil and vapors from the crankcase, as well as the head ventilation system. This will prevent oil from coating the intake manifold which will make can make its way onto the valves which will affect the octane rating which leads to detonation issues and performance issues. 

 

 

DETAILS:

  • Anodized black finish option with white GrimmSpeed logo
  • The unique design utilizes the factory oil filler cap location to maintain your PCV system
  • Prevents harmful oil and oil vapors from entering the crankcase and head ventilation system
  • Prevents the reduction of fuel octane
  • Prevents the higher chances of engine knock and detonation
  • Prevents worse emissions 
  • Prevents higher oil consumption 
  • Very compact design
  • Coalesces oil without using a mesh media which can cause contaminants to collect and cause a sludge buildup
  • The design eliminates the need to check/empty your catch can while refilling your oil 
  • Includes all of the required fittings
  • Includes hose that is cut to specific lengths and zip ties
  • Product Video

    Specifications

    Brand: GrimmSpeed
    Color: Black
    Installation Hardware Included: Yes
    Material: Aluminum
    Mfgr. Warranty: Lifetime
    Condition: New Product
    Return Policy:
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    PEOPLE WHO VIEWED THIS ITEM ALSO VIEWED

    REVIEWS & CUSTOMER MEDIA

    40 Reviews
    4.6 out of 5 Stars
    5 Stars
    (30)
    4 Stars
    (5)
    3 Stars
    (3)
    2 Stars
    (2)
    1 Stars
    (0)
    Customer Photos and Videos
    GrimmSpeed Air Oil Separator ( Part Number: 078006)
    GrimmSpeed Air Oil Separator ( Part Number: 078006)
    GrimmSpeed Air Oil Separator ( Part Number: 078006)
    GrimmSpeed Air Oil Separator ( Part Number: 078006)
    GrimmSpeed Air Oil Separator ( Part Number: 078006)
    GrimmSpeed Air Oil Separator ( Part Number: 078006)
    GrimmSpeed Air Oil Separator ( Part Number: 078006)
    GrimmSpeed Air Oil Separator ( Part Number: 078006)
    GrimmSpeed Air Oil Separator ( Part Number: 078006)
    GrimmSpeed Air Oil Separator ( Part Number: 078006)
    GrimmSpeed Air Oil Separator ( Part Number: 078006)
    GrimmSpeed Air Oil Separator ( Part Number: 078006)
    GrimmSpeed Air Oil Separator ( Part Number: 078006)
    GrimmSpeed Air Oil Separator ( Part Number: 078006)
    Mandatory For Boosted Motors 2 years ago
    4out of 5stars
    MasterFlex
    Installed on an 07 Forester XT. A catch can or AOS is mandatory for turbocharged engines. Easy install, and the install kit comes with plenty of hoses and fittings. It is a little pricey for what is basically an aluminum cylindar with three tubes and a cap, but it is a solid solution that does not require emptying a catch can or heavily retrofitting something.
      
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    1 of 1 people found the following review helpful
    Used this for years, now don't 3 years ago
    2out of 5stars
    finchpunk
    I had this on my car and used it for years, it isn't that great at doing its job. I had to continually clean the separator as it would get bubbles in the oil and would gather foam around the top. These bubbles never made it to the oil pan, only inside the AOS. I finally got a IAG air oil separator and its way better. Would never go back.
      
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    2 of 4 people found the following review helpful
    Easy to install but not worth it 3 years ago
    3out of 5stars
    Mitch
    I’m currently finishin my mild build (400-500whp) and my nationally renowned tuner informed me that this part is only good for one thing ... “Having to use a wrench to put oil in your car” and instructed me to get the IAG AOS instead.
      
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    2 of 2 people found the following review helpful
    Works great! 4 years ago
    5out of 5stars
    ITSTHEBLOB
    Currently tuning my JDM EJ swap and found oil build after the intercooler and before intake manifold. For my street driven WRX, this AOS has completely removed the oil from the intake and my runner is happy since it reduced knock issues after it was installed. I plan on tracking pretty soon and plan on adding a catch can In line with the hose that runs to the intake, as a just incase. But yeah this thing is great and isn't an eye sore in the engine bay.
      
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    1 of 1 people found the following review helpful
    necessary upgrade.. 4 years ago
    5out of 5stars
    JoshSti
    Received the item well packed, great quality, all necessary parts included, BUT I wished they included hose clamps, rather than zip ties, and NO instructions included, luckily it was easy to install, and the instructions are available online or YouTube videos is a good source. After installing this AOS on my 2005 Sti, I felt the difference after driving the car for few miles, runs great and smooth. I definitely recommend this for your daily driver. Not sure for racing yet.
      
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    QUESTIONS & ANSWERS

    • Q: Oil Change/Filling  pferrante43 years ago

      Does this make changing the oil (or filling at the gas station as all of us Subie drivers occasionally need to do) a pain? Are the core and outside pieces real tough to separate, or does it just take some light wrenching?
      • 0 of 0 people found the following answer helpful

        A:  It's literally my only gripe with it. So yes, unfortunately it does make it a pain, as you will use a 19mm socket or wrench to open it up, Honestly it's not too bad, but it is something to think about for sure. Thanks!

        Rick C. @ RallySport Direct 3 years ago  
          
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    • Q: Street /track  13stisedan4 years ago

      Hi I read a review from a few years ago here about the older version of this AOS not seperating properly after heavy track use causing it to smoke from the cap seal and it was stated that GS is aware and working on an update? I'm guessing because of the style of this AOS that a proper track version isn't in the works?
      • 0 of 1 people found the following answer helpful

        A:  I would recommend looking at other options if you are going to use your car on the track

        Devan M. @ RallySport Direct 4 years ago  
          
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    • Q: Fitment  dmonti117399518 years ago

      Someone is selling one of these off of a 2012 wrx, why will a 2012 STI confirm fitment but not a 2012 wrx? It is just the part that screws in and i am wondering if its just that particular part will it work?! :)
      • 0 of 0 people found the following answer helpful

        A:  The 2008-2014 WRX models have a very different setup when it comes to induction and ventilation, it may be adaptable but this is not a direct fit and purchasing the correct AOS for your vehicle is recommended for ease of install.

        Nick S. @ RallySport Direct 8 years ago  
          
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    • Q: Install video valid on 15 STI?  wongchonghing852588 years ago

      Was curious if the install video applies for the 2015 STI? All step and procedures are the same in the video for installation on 2015 STI?
      • 0 of 1 people found the following answer helpful

        A:  The install should still be the same on your car.

        guest56ad69792a8d256e198b66b5 @
          
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    • Q: Power Rating  sikknt8 years ago

      Does this still work if you're running 400hp?
      • 0 of 1 people found the following answer helpful

        A:  This will still work with no issues.

        Kyle A. @ RallySport Direct 8 years ago  
          
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      • 0 of 1 people found the following answer helpful

        A:  Horsepower shouldn't be a limiting factor as long as your engine is running healthy and has no more than factory amounts of blow by. Mike

        GrimmSpeed
          
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