Original 1971 429 Cobra Jet engine........should be reunited with the original chassis!!

[Don C]

F is Dearborn. Torinos and Thunderbirds also had the 429 in 1971. They were called Thunderjet in the Thunderbirds.

 

[Hemikiller]

Three plants built Mustangs - San Jose - R, Metuchen - T and Dearborn - F. San Jose stopped Mustang production prior to the 71 model year. Metuchen stopped Mustang production on Dec 23, 1970 (my Mach was built 12/22/70) and Dearborn was the sole Mustang plant from then until the end of 73 model year production. 

Dearborn did build Cougars concurrently with Mustangs, as noted with the 5xxxxx unit numbers. 

Lorain, Ohio - H, and Atlanta, GA - A,  built the Torino & Montego in 71, so what one may think to be and "F" might actually be an "H". 

 

[ib4stangs]

A cop friend once told me they can recover ground off serial numbers. After reading this thread I did a quick search and found this article of interest. Especially the last paragraph. So there are ways to find out, but not very easily...

Scientists develop a technique to find serial numbers that have been filed off - The Washington Post

 

[Bentworker]

Try sponging some phosphoric acid on it and keep it wet (with additional phosphoric acid) for 20 minutes or so and wipe it off.  You can get it at Home Depot or Lowe’s in the concrete section.  It won’t eat the metal, but I have seen it offer a different shade of grey where stampings were.

 

[Don C]

I don't think the VIN has been filed or ground off. I think the assembly line worker whose job it was to stamp the partial VIN was hung over and hitting the stamps hard with the hammer reverberated through his or her head, or maybe was using a rubber mallet to keep the noise down  :biggrin:

 

[mjlan]

Ha!

That's a good catch with the possible H in the partial!

 

[Stanglover]

Ah, so I wasn't wrong for a change. T is Metuchen  as I thought. 

As Matt just said, if it is an H not an F then this is going to get interesting. I'm staying tuned!

 

[Fabrice]

What is the stamp on the heads?  They should be DOOE-R if the engine is from a CJ car.

 

[fordismyboss]

Yes, they are D0OE-R and the date code is SPEC. It appears the heads have never been off the engine, and the seller also stated this.

 

[Fabrice]

That alone is a great news. These are made of pure unobtanium

 

[Sheriff41]

Didn't the Mercury Cyclones use the 429 CJ also?  Not sure what their VIN sequences were.

 

[fordismyboss]

Ha!

That's a good catch with the possible H in the partial!

With four horizontal lines in that "double-struck" F, it can't be an H. Also, did Lorain (H plant code) ever build any 429 CJ motors? I think they were all built at Dearborn by 1971, even for Torino Cobras. Inputs please!





 


 

 

[fordismyboss]

I just added this document to the original thread. For all of you guys like me that like the numbers and stuff!!!

 

[mjlan]

I have been trying to figure out what the 'SPEC' date code on CJ/ SCJ heads means. What I have come across is not consistent.

Theory #1 is that 'SPEC' were early heads. If this is the case they would be on early '70 MY engines (so engines with '69 casting dates and build dates) as the first CJ's were in the Torino line. I think this is unlikely.

Theory #2 is that the 'SPEC' dates codes were for SCJ heads that were earmarked to get guide plates. This seems to me more likely as it would indicate something different in the head casting process. But I don't think there is a difference in the head itself between a non-adjustable CJ head and an SCJ head  that had non-shouldered studs and guide plates.

If you have confirmed that the block is indeed a four-bolt main block and the heads are 'SPEC' date codes to me that indicates an SCJ engine, not a CJ.

What type of camshaft is in it? 

If you've had the intake off, any chance you have the block casting date?

I'm always interested in engine dating of possible original engines. My J-code engine is long gone and shopping for parts is more rewarding when you can find stuff with dates that possible match what would have come originally.

 

[fordismyboss]

Bring-A-Trailer is getting very close to starting the auction. Might be up by this weekend. I'll send the link as soon as I know. Thanks to all for participating in this discussion.

 

[fordismyboss]

The auction is now live on Bring a Trailer: https://bringatrailer.com/listing/1971-ford-mustang-429-cobra-jet-c-code/

Thanks to all for contributing. I hope this motor can be reunited with its original chassis, or put back in a 1971 mustang/cougar soon!

 

[8850dave]

When I read you found this 429scj motor near Sheridan, IL it’s in my back yard so I probably know the guy you bought it from in that town. My ‘71 J code doesn’t have the original motor either or does my ‘70 Torino Cobra with J code

 

[william binegar]

looking at the partial serial number, the 1st 1 looks like a 4 year i know it does not make sense. the F does look like an F, but could it be a P? maybe this engine is a 1971 429 police interceptor from a car built at the twin cities. again it does look like an F. and before you all get in a huff a 1971 429 police interceptor was just a renamed 429 cobra jet. the next number after the F i could not make out, but could it be a 5 ? again i can't make it out i like the next 2 as 73, but the next one which is also hard to see, could it be a 1? just saying, the last 2 look like 52 or 53 that being said if i was to contact Kevin Marti to try and figure a serial number by what i see, I would try 1F05J173152 0r 53, or 1F93C573152 but it could be about anything. good luck on your search.

 

[william binegar]

I have been trying to figure out what the 'SPEC' date code on CJ/ SCJ heads means. What I have come across is not consistent.

Theory #1 is that 'SPEC' were early heads. If this is the case they would be on early '70 MY engines (so engines with '69 casting dates and build dates) as the first CJ's were in the Torino line. I think this is unlikely.

Theory #2 is that the 'SPEC' dates codes were for SCJ heads that were earmarked to get guide plates. This seems to me more likely as it would indicate something different in the head casting process. But I don't think there is a difference in the head itself between a non-adjustable CJ head and an SCJ head that had non-shouldered studs and guide plates.

If you have confirmed that the block is indeed a four-bolt main block and the heads are 'SPEC' date codes to me that indicates an SCJ engine, not a CJ.

What type of camshaft is in it?

If you've had the intake off, any chance you have the block casting date?

I'm always interested in engine dating of possible original engines. My J-code engine is long gone and shopping for parts is more rewarding when you can find stuff with dates that possible match what would have come originally.

All 429 cobra jet heads got guide plates, the differance was the stud, not that one had a guide plate and the other didn't. although i do not know the spec part, other than ford used special a lot for their high-performance engines. (in the parts books boss 302, boss 429, and boss 351 engines were listed as specials, and maybe the 429 cj was also going to be one of the special engines) If i had to guess it was one of the 1 st mold for the 429 cj heads, that never got revised to use a date code, or at least revised later. Or the heads are off an early engine, i have seen engines that had a spec head, and one with a date code, but they were early 1970 engines. Plus i am sure the assembly workers would not be looking though a pile of heads to check the date code or for spec heads, when assembling heads.

 

[AcesArneson]

351CJ underwent a name change to 351 4V in 1973. Same year it was equipped with the smaller valves and open chamber heads.

 

[mjlan]

All 429 cobra jet heads got guide plates,

You are right, messed that theory up!

I've also heard that special was early production.

It could be that it was pre-release or PPAP work that would have been scrapped if there were issues but used if they were good.