Author Topic: Shelby 9' Rear End Center Section Question?  (Read 5354 times)

rcgt350

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Re: Shelby 9' Rear End Center Section Question?
« Reply #15 on: December 17, 2018, 11:07:57 PM »
Could SPEC be an abbreviation for Special?

gt350hr

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Re: Shelby 9' Rear End Center Section Question?
« Reply #16 on: December 18, 2018, 10:57:53 AM »
  Yes it is! The question nagging me for years is why the foundry changed it's practice of using that area for the casting date. My friend Kerry Wortman has narrowed down the date of time these were cast in ( '67 only) but finding a Detroit Iron Foundry worker that can say "why" it was done has not happened. The SPEC tag has been used on cylinder heads and other parts and so far the only tangible possibility (IMHO)was these parts were cast at the small run "specials" foundry , not the huge Detroit Iron Foundry that normally did them. Again "why" hasn't been answered. I know there is a specific reason that will get a "of course , that's why" response but it remains "to be discovered". My "educated guess" could also explain why a single rib version exists.
    Randy
Celebrating 46 years of drag racing 6S477 and no end in sight.

Bigfoot

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Re: Shelby 9' Rear End Center Section Question?
« Reply #17 on: December 18, 2018, 03:13:49 PM »
SPEC case on my 68.5 Survivor Car.
RIP KIWI
RIP KIWI

rcgt350

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Re: Shelby 9' Rear End Center Section Question?
« Reply #18 on: December 18, 2018, 03:54:23 PM »
Perhaps by 1969 Ford switched to labeling with the N . Was the N case made in the regular foundry or still in the other Special foundry?

gt350hr

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Re: Shelby 9' Rear End Center Section Question?
« Reply #19 on: December 19, 2018, 12:34:29 PM »
    Randy,
 
         The DIF letters found on castings refers to the Detroit Iron Foundry.  CF and WF are on parts cast at Cleveland and Windsor  Canada ( respectively). "I" am PURELY guessing ( though an educated guess) that the SPEC instead of the date code was done because of a foundry change. I have NOTHING to back it up on except my knowledge of other parts that had SPEC on them. Not all of those parts with  the SPEC on them were "performance" parts but some were. I have above average knowledge  for a "non Ford plant worker" ( from years of study and interviews of those who did work for Ford) as to how things were done "in the day"  I do NOT know it all and never will. I learn something new every day. Until I ( or anyone else) can validate my GUESS , use caution in repeating it. That is how "myths " get started.
     Randy
Celebrating 46 years of drag racing 6S477 and no end in sight.