Approval Details

Valid E.O.


This Executive Order approved the specified parts on on June 28, 1993.
As of Sunday, July 21st, 2024 this Executive Order has not been overturned or superceeded.

Approved Parts

Part NumberModelsModification
300hp1986-1993 Ford Mustang 5.0L V8 gasoline enginesRelocation of air injection hoses. Retard ignition timing from 10 degrees BTDC to 5 degrees BTDC. Install one -way check valve between PCV and inlet manifold.
375hp1986-1993 Ford Mustang 5.0L V8 gasoline engines

This Executive Order may be listed as:
  • C.A.R.B.E.O. D-321
  • Executive Order 321 / D321
  • ARB # D-321
  • Executive Order No: D-321
  • C.A.R.B. No. D-321
  • Resolution D-321
For Free CARB Executive Order Status verification, email an image of the device Executive Order label as well as the Year/Make/Model and Test Group # of the vehicle to [email protected]

Download: Executive Order D-321 PDF

D-321 Document:

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