Cosworth Air Pump Delete Plates ( Part Number:COS1 20004539)

Cosworth Air Pump Delete Plates

MODEL # COS1 20004539
Manufacturer Part # 20004539


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Used to eliminate the air pump and related valves found on 2006-2008 Subaru Engines. Used for high performance applications or adapting later cylinder heads to early engines. Seals off the air injection ports at the cylinder heads. Saves weight, reduces complexity, cleans up engine compartment. Machined from solid aluminum with a "Cosworth blue" anodized finish. Mounting hardware included.
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Brand: Cosworth
Installation Hardware Included: Yes
Material: Aluminum
Quantity: 2

Mfgr. Warranty: 1 year
Condition: New Product
Return Policy:

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Verified Purchase

No problems
guest55c54491caae52c1228b9640 2 years ago
They do what they are made to do works fine and looks great
Verified Purchase

Look great, but their not Blue
sbobowski 3 years ago
I just received mine today. I can't wait to install them on my new engine. contrary to what the description of the product says (Machined from solid aluminum with a Cosworth blue anodized finish) mine are very much not blue they are gray, but they still look great.
Verified Purchase

Cosworth Air Pump Delete Plates Subaru 2006-2008 Turbo Models (inc. 2007-2008 STI)
JRTECHSVC70220 5 years ago
No questions asked, top quality product....AAA+++
Verified Purchase

No Issues
1FASTWREX 5 years ago
Fit great no issues, but just to let you know they do not come with new gaskets. Have to reuse old ones or order new ones. The gaskets are stainless though. Love the fasteners they come with.

  • Q: gaskets  danielspead15589 2 years ago


    do you still use gaskets with this delete kit or no gasket needed since both the block and plates are flat faces ?

    • A: Gaskets should be used with these plates, and the gaskets need to be purchased separately.

      Zach G. 2 years ago
  • Q: P2433 code  Mattfryday187 2 years ago


    If I delete the air pump will this code go away? I just changed out my maf sensor and its still going off. But the p2431 code went away. Also will it affect my emissions getting rid of it or having the code going off?

    • A: Air pump deletes will cause a check engine light and the only fix would be the calibrate the ECU to ignore it. These parts are meant for offroad use only and we cannot comment on emissions.

      Nick S. 2 years ago
  • Q: use  manny d 2 years ago


    how is this useful besides weight reduction and faulty codes? does this help in power and airflow??

    • A: This is mainly just to delete the air pumps and slight weight reduction. There are not really any other benefits to this piece.

      guest57853c642a8d25b5018c44a7 2 years ago
  • Q: Gaskets  corkyluu89054 3 years ago


    Does this include the gaskets for the plates?

    • A: No gaskets are included.

      Kirill C. 3 years ago
  • Q: will it fit  nightscottimeful20686 4 years ago


    is this known to fit on a 09 wrx?

    • A: Cosworth has not confirmed fitment on the 2009 WRX at this time.

      Zach G. 4 years ago
Subaru Impreza
WRX STI 2007WRX STI Limited 2007WRX STI Hatchback 2008, 2009, 2010, 2011, 2012, 2013, 2014WRX STI Special Edition Hatchback 2010WRX STI Limited Hatchback 2011, 2012, 2013, 2014WRX STI Limited Sedan 2011, 2012, 2013, 2014WRX STI Sedan 2011, 2012, 2013, 2014WRX 2006, 2007WRX Limited 2006, 2007WRX TR 2006, 2007WRX Hatchback 2008, 2009, 2010, 2011, 2012, 2013, 2014WRX Sedan 2008, 2009, 2010, 2011, 2012, 2013, 2014WRX Limited Hatchback 2010, 2011, 2012, 2013, 2014WRX Limited Sedan 2010, 2011, 2012, 2013, 2014WRX Premium Hatchback 2010, 2011, 2012, 2013, 2014WRX Premium Sedan 2010, 2011, 2012, 2013, 2014
Subaru Legacy
GT 2006GT LIMITED 2006GT spec.B 2006, 2007, 2008, 2009GT Limited 2007, 2008, 2009
Subaru Outback
XT 2006XT Limited 2007, 2008
Subaru Baja
Turbo 2006
Subaru WRX STI
Base 2015, 2016, 2017Launch Edition 2015Limited 2015, 2016, 2017Series.HyperBlue 2016
Saab 9-2X
Aero 2006