429 Production Question

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1971 mustang Mach 1, 429CJ, J Code SOLD 3/2016

1971 Boss 351 Mustang
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I have tried to find out when Ford stopped production of the 429 Mustangs/Cougars.

(I also read somewhere the 429 Cougars were built on the same assembly line as the 429 Mustangs, anyone heard that?).

I know they were only built at the Dearborn factory. Does anyone know what actual month they stopped building them? All I have ever read was simply "mid year" the 429 engines were no longer available.

Anyone have an idea or seen any sort of documentation on this subject? I checked the 429 Mustang/Cougar Megasite but did not see that information. All I found there was that there were 429 cars produced in August of 1970 but they were not available or sold to the public until September of 1970. I have seen nothing about when the last 429 car was produced or when Ford officially dropped the availability of the 429 engine option.

 
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I have tried to find out when Ford stopped production of the 429 Mustangs/Cougars.

(I also read somewhere the 429 Cougars were built on the same assembly line as the 429 Mustangs, anyone heard that?).

I know they were only built at the Dearborn factory. Does anyone know what actual month they stopped building them? All I have ever read was simply "mid year" the 429 engines were no longer available.

Anyone have an idea or seen any sort of documentation on this subject? I checked the 429 Mustang/Cougar Megasite but did not see that information. All I found there was that there were 429 cars produced in August of 1970 but they were not available or sold to the public until September of 1970. I have seen nothing about when the last 429 car was produced or when Ford officially dropped the availability of the 429 engine option.
This assembly line pic of a Boss 351 and a 71 Cougar should answer your shared assembly line question:

294p9op.jpg


Even though you didn't find your answer on the 429 Megasite - I would suggest you post your production timeline question on their forum. They are a great source of knowledge for those cars.

Good luck! Ray

 

kidwithfastback=fast

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1972 Fastback (Factory sprint, but now a bright red Mach 1)
351c 2v(big ol cam, holley dominator intake, roller set, edelbrock 4bbl)

fmx
the emissions/gas crisis basically snuffed out big blocks in 71, i think. Not positive on that.

 
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Kit Sullivan

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There was no "gas crisis" in 71...that came in 74. Emissions regulations were certainly an issue and were causing manafacturers to produce lower-powered engines, but they could still sell them if they wanted to.

The primary reason the high-performance engine-options were dropped by Ford after 71 is due to the insurance industry jacking the rates for performance cars up so high that they became unaffordable to those trying to buy them. This slowed sales dramatically, leading to cancellation of those options.


That photo above shows what appears to be Ford's substandard assembly-line quality of the day: The alignment of the trunk lid on the Cougar is noticeably off, and on the Mustang (cool BOSS 351!), either the trunk lid is misaligned on the right side, or it could be the paint break is misapplied. Either way, they both look sloppy for brand new.


That picture is also pretty definitive proof that BOSS 351s did NOT come with rear-valance cut-outs or chrome exhaust tips, as did the Mach 1s.

There has been some debate over this issue for many years.

 
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I received an e-mail from Kevin Marti on the question I had about when during the 1971 model year was the 429 engine option no longer available. The quote below is from Kevin Marti.

Quote: "Production of the 429 engine continued through the entire model year. There was not an early cutoff for this engine."

I was not aware of this. I thought that sometime during the production year both the Boss 351 and the 429 engine was dropped during the model year.

 
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Not definitive but maybe this will help on the Boss 351's.

From the very inactive Boss 351 website

http://www.boss351registry.com/FAQ-1.htm

When was the first and last BOSS 351 built ?

[First: Don't know. The earliest "date invoiced" on a build sheet of a Boss 351 is 11/5/70. (3 cars).

Last: The last invoice date on a build sheet of A Boss 351 was July 27th, 1971]

Remember - a de-tuned version of the Boss 351 engine was available in all 1972 Mustang body types; aka 1972 351HO. Cool cars IMHO.

Ray

 

Adrian Clements

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I do not own a 1971-1973 Ford Mustang, but am requesting admission to the forum so that I can learn about these cars.
I own 6 1967 FoMoCo products: 5 1967 Ford full-size cars, and 1 1967 Meteor (a product of Ford Motor Company of Canada, Ltd.).
Folks,

The 1,865 Ford Mustangs produced during the 1971 model year with the C-code 429 CJ & SCJ non-Ram Air engines and the J-code 429 CJ & SCJ Ram Air engines were built between August 3, 1970 and August 5, 1971 - the entire 1971 model year.

Similarly, the 449 Mercury Cougars produced during the 1971 model year with the C-code 429 CJ non-Ram Air engine and the J-code 429 CJ Ram Air engine were built between August 3, 1970 and August 3, 1971 - the entire 1971 model year.

Yours in old Ford iron,

Adrian

 
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1971 Boss 351 Mustang
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Folks,

The 1,865 Ford Mustangs produced during the 1971 model year with the C-code 429 CJ & SCJ non-Ram Air engines and the J-code 429 CJ & SCJ Ram Air engines were built between August 3, 1970 and August 5, 1971 - the entire 1971 model year.

Similarly, the 449 Mercury Cougars produced during the 1971 model year with the C-code 429 CJ non-Ram Air engine and the J-code 429 CJ Ram Air engine were built between August 3, 1970 and August 3, 1971 - the entire 1971 model year.

Yours in old Ford iron,

Adrian
Thanks Adrian,

Your an asset to this site with great information. It is really nice to know about the history of these really nice cars that survived all these years.

 

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