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GrimmSpeed Air Oil Separator for Subaru WRX STI

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Subaru WRX STI
 
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2004 to 2007
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2004 to 2007
Sedan [All]
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2008 to 2014
All [All]
(Black)
2008 to 2014
All [All]
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2015 to 2021
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(Black)
2015 to 2021
Sedan [All]
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The GrimmSpeed Air Oil Separator does exactly what the name implies; removes airborne oil from the engine ventilation system and keeps the intake system free of oil. Removing oil from the intake system is very important because airborne oil lowers fuel octane, increases the risk of detonation, increases emissions and adds to oil consumption. The GrimmSpeed AOS (Air Oil Separator) can be used in conjunction with the stock PCV system to reduce the airborne oil and allow better engine efficiency, higher octane/reduced detonation and less oil consumption.

The GrimmSpeed AOS is a compact good looking design that replaces your stock oil cap and filters oil out of crankcase and cylinder head vapors and provides clean air to your intake ventilation system. Unlike other catch cans the GrimmSpeed AOS does not need to be checked or emptied constantly. The Air Oil Separator does not use the normal mesh media that can allow contaminates and sludge to collect but rather a self maintenance design that allows the driver to relax and enjoy driving!

Key Features:
  • Increases octane by removing octane lowering oil vapors.
  • Reduces oil contamination from the intake system.
  • Works well on stock and modified vehicles.
  • Allows use of stock PCV system.
  • 19mm cap can be easily removed with a common lug nut wrench.
  • Compact attractive design that works with front mount (FMIC) or top mount (TMIC) intercooler setups.
Usage Notes: This system is designed to work with normal levels of blow by gasses. If you have an engine with excessive amounts of blow by gasses (built motor or higher mileage engine with loose ring gaps) a standard catch can may be a better match.

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