Author Topic: What this number means.?  (Read 1346 times)

Offline Josep

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What this number means.?
« on: December 07, 2015, 08:00:39 AM »
Hello all,

noticed a casted number "13" (attached pic) on the bottom part of the engine, in the drivers side. What this means.?
Also, this number 6E25_ . Looks like the top part of the number was not well casted, but I'm pretty sure is this number. See pics please. What's the significance of this 25 May 66..?

6R07T213966 San Jose build 11 June
1966 Mustang Hardtop 200 Inline 6 - Arcadian Blue - C4 - Thermactor - 6R07T213966 - San Jose projected build date June 11th 1966 - DSO 71
1966 Mustang Convertible 289-2V - Vintage Burgundy - AT PS DB - 6F08C109403 - Dearborn projected build date September 9th 1965 - DSO 36

Offline GT500KR

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Re: What this number means.?
« Reply #1 on: December 07, 2015, 08:34:58 AM »
Guessing, but the cast "13" probably refers to the mold used for the casting. Stamped numbers look like assembly date code in this case May 25 1966.
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Offline Richard P.

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Re: What this number means.?
« Reply #2 on: December 07, 2015, 09:30:06 AM »
Guessing, but the cast "13" probably refers to the mold used for the casting. Stamped numbers look like assembly date code in this case May 25 1966.
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Offline J_Speegle

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Re: What this number means.?
« Reply #3 on: December 07, 2015, 04:57:53 PM »
Also, this number 6E25_ . Looks like the top part of the number was not well casted, but I'm pretty sure is this number. See pics please. What's the significance of this 25 May 66..?

That is when the engine (in this case a 6 cylinder) was assembled - last letter would have been an initial for the worker who assembled it for accountability purposes
Jeff Speegle

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Offline Josep

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Re: What this number means.?
« Reply #4 on: December 07, 2015, 07:25:06 PM »
That's what I guessed. Many thanks all for your interesting and helpful posts.
1966 Mustang Hardtop 200 Inline 6 - Arcadian Blue - C4 - Thermactor - 6R07T213966 - San Jose projected build date June 11th 1966 - DSO 71
1966 Mustang Convertible 289-2V - Vintage Burgundy - AT PS DB - 6F08C109403 - Dearborn projected build date September 9th 1965 - DSO 36