We custom make these with the specific date that is chosen. Please allow 2-3 weeks from when the order was placed to ship. 

Description: BOSS 429 Anti-Backfire Valve / Diverter Valve
Year: 1969-70
Engine: BOSS 429
Model: Mustang BOSS 429
Engineering #: C8OE-9B289-C
Model #: 4491S
Date Code: YES (Indicate your cars production date when ordering)

Accuracy Rating: 8
Best Repro Available: YES

Jack's Comments:

This is the best available BOSS 429 anti-backfire (diverter valve) on the market today. The FORD oval, CARTER ST. LOUIS MO., engineering number, model number and date code die stamps are all the correct font, size and location. Its fully functional so it will perform just like a factory original.

Date Codes:
We ask you to specify your BOSS 429's production date when ordering and we will date code it a month to a month and a half before your cars production date. If you want a specific date let us know in the Special Instructions: Box. Please allow a few extra days for delivery for us to apply the date code.

Concours Notes:
1) The smaller housing cover with the FORD stamp was anodized aluminum on production diverter valves. This reproduction is clear zinc. Not very noticeable when installed.
2) The location of the die stamped engineering number, date code and model number is located on the lower cover were it can be clearly seen when installed. Originals were indexed in random locations.

Questions & Answers:

Q: How do you decide what date code is right for my BOSS 429?
A: When you specify your cars production date we take a look at our vintage calendars and select a day one to one and a half months before your car was built.  If you would like to specify a date you want your alternator stamped with just let us know in the Special Instructions: box.  

Q: What clamps are correct for this diverter valve?
A: Passenger and driver side air injector hoses use a #7 Wittek clamp (yellow zinc) at both ends, the very hard to find clamp that secures the valve to the bracket is #30 Wittek clamp (zinc galvanized). The S-Hose uses two Wittek tower clamps (yellow zinc).