Topic: Approximate DoM of my recently-purchased 1966 convertible and other details

[RichandBen]

Hi all, due to the history of the car I have just bought (more details in my first post), there is no data plate so I don't know many of the details of it, including when it was built at Dearborn. Is the VIN - 6F08C3096xx - sufficient to get the Date of Manufacture nailed down? I have a tag akin to a Dymo label that was glued in the engine bay above the solenoid, that has the name and address of the original owner and the date 4 November 1966. Also, is there a way that I can visually determine the differential ratio?

Cheers

[carlite65]

there should be a tag affixed to the rear axle stump with the ratio on it.

[RichandBen]

Crikey, that was quick; thank you.

[carlite65]

someone here with a 1st edition of mustang production guide can narrow down the build date pretty closely. the only numbers on your door tag that will remain a mystery are the dso. everything else can be determined by the car itself. treat it as an archeology exercise.

[RichandBen]

That sounds like fun, I look forward to crawling all over and under the car to see what I can find. Would I be correct in thinking that the DSO code is most likely that for New York or Newark? Does the fact that the car has the Thermactor system installed bring a DSO further afield into consideration?

[midlife]

Thermactor system indicates a California DSO. 
Vin is consistent with an 03-06D date code, or 03-06 April 1966. 

[jwc66k]

You should check and see if the engine is original to your car. An easy way is to check the engine assembly date which is located on a small extension of the engine block near the distributor (see the pictures). It is in the format of year (a number), the month (a letter, A thru M, A = January, M = December), the date (one or two numbers, 1-31) and the assembler/inspector's ID (a letter). The one in the picture is 5H23Z, which decodes to 1965, August, 23 (the day), and code "Z" for the assembly/inspector. That date should be before the scheduled build date of your car, which has been calculated to be 3-6 April 66 (I verified it), about a week to a month. It would be something like "6C04Z" to "6D01Z".
I am leery as to your car having a California DSO of 71 or 72 as those two DSOs are not common on the cars listed in the Mustang Production Guide in that time period. The earliest California DSO is at the end of February, 1966, the one after your car was scheduled to be built was in July, 1966 (a "K" code convertible to DSO 71, LA). 
Jim

[RichandBen]

This is all highly-fascinating. The hundred cars in the 3096xx were manufactured in a four-day period; do the records you guys are referring to narrow the date down based on an individual VIN, say 309655 built on April 4th, 309666 on the 5th or whatever ? Was California the only state that Thermactor-equipped cars were sold in, or could customers anywhere in the US buy such a car?

[RichandBen]

Attached is a photo of the inlet manifold that Richard removed from the engine because it was missing at low RPM (diagnosed as an induction leak between two cylinders). My understanding is that the 6C9 code near the front indicates a casting date of March 9, 1966. Is that correct? I can?t check anything on the car because Richard has it at his place and we live in different states.

Thanks for your replies so far and Cheers
Ben

[daniel94]

Attached is a photo of the inlet manifold that Richard removed from the engine because it was missing at low RPM (diagnosed as an induction leak between two cylinders). My understanding is that the 6C9 code near the front indicates a casting date of March 9, 1966. Is that correct? I can?t check anything on the car because Richard has it at his place and we live in different states.

Thanks for your replies so far and Cheers
Ben

The 6C9 appears correct to me.  Additionally, you also have the engine tag there with 6-C (March 1966).  Since it would be expected for the engine to be assembled within a few weeks of the car assembly, this also lines up for the dates you've been given, in my opinion.

Also, essentially every piece of stamped sheet metal on the car should have a date code stamped into it if original.  See if you can find a few of these as well for clues.

[jwc66k]

My understanding is that the 6C9 code near the front indicates a casting date of March 9, 1966. Is that correct?

The date is correct for the manifold being cast, not the engine assembly date.

- do the records you guys are referring to narrow the date down based on an individual VIN, say 309655 built on April 4th, 309666 on the 5th or whatever?

The information I used came from the "Mustang Production Guide, Vol 1" (it's out of print) for 64 thru 66 Mustangs built at all three Ford Assembly plants. It was compiled by Jim Smart and Jim Haskell from information gathered from Mustang owners (plus a couple of states vehicle registration data). It is by no means complete. It does give a broad look at how Mustangs were equipped. The "build date" is actually a "scheduled build date". It's still close.
Jim

[J_Speegle]

Hi all, due to the history of the car I have just bought (more details in my first post), there is no data plate so I don't know many of the details of it, including when it was built at Dearborn. Is the VIN - 6F08C3096xx - sufficient to get the Date of Manufacture nailed down?..................

No not at all. At best you can guess the date that was stamped on the door tag but that was the date some operator guessed when the order was received at Dearborn. Could be off by weeks but that appears to be what your looking for rather than when the car was really built/completed