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matching numbers

  • Thread starter Thread starter asiantony
  • Start date Start date Jul 14, 2006
A

asiantony

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Oct 1, 2005
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Jul 14, 2006
#1
  • Jul 14, 2006
  • #1
hi guys,

i've got a 66 fastback with a 289. how can i tell if it's the original engine that came with the car? where are the numbers stamped on the block? how do they correlate with the VIN numbers? any help is much appreciated!
 
D

D.Hearne

New Member
Sep 29, 2000
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south louisiana
Jul 14, 2006
#2
  • Jul 14, 2006
  • #2
No vin numbers on a 65. Look at the casting numbers above the starter, there you'll find the casting and date code. Date code is a number/letter/number(s) combination. 1st number is the year of the decade it was cast, the letter is the month code starting with A and aphabetically to M for december, they skipped the letter "I". The 3rd number or numbers is the day of the month it was cast. The decade is determined by the first two numbers of the casting number. Yours should be a C4 or C5, most likely C5
 
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asiantony

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Jul 15, 2006
#3
  • Jul 15, 2006
  • #3
same thing applies to 66 mustangs?
 

dennis112

15 Year Member
May 15, 2005
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Amish Wonderland of Central PA.
Jul 15, 2006
#4
  • Jul 15, 2006
  • #4
asiantony said:
same thing applies to 66 mustangs?
Click to expand...

Yes, except the casting codes could begin with either a C5 or a C6.
 

BarnStang

Founding Member
Mar 2, 2001
1,260
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Hagerstown, MD
Jul 15, 2006
#5
  • Jul 15, 2006
  • #5
You can decode the whole number here:
http://www.mustangsandmore.com/ubb/FordTechData.html
But you can't take this as written in stone. Iv'e been told that they could put engines from other lines in the Mustang if they ran out and had cars to finish? So you could have an engin coded for a Falcon or a Fairlane, but was put in on the assembly line. Don't know how accurate that is...
 
D

D.Hearne

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Sep 29, 2000
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Jul 16, 2006
#6
  • Jul 16, 2006
  • #6
BarnStang said:
You can decode the whole number here:
http://www.mustangsandmore.com/ubb/FordTechData.html
But you can't take this as written in stone. Iv'e been told that they could put engines from other lines in the Mustang if they ran out and had cars to finish? So you could have an engin coded for a Falcon or a Fairlane, but was put in on the assembly line. Don't know how accurate that is...
Click to expand...
The product line the block was cast for means nothing. I don't believe there's any "Z" coded blocks in 289's. They're all either "O" or "A" in the third character. Just because the third character denotes one vehicle, doesn't mean that's the vehicle it was installed in. That's the case maybe half the time. Ford never cast one particular engine block for one particular car. Take for instance the 428 CJ, the block casting numbers says it's a Mercury block, but there were more of these engines put into Stangs than Mercs. Same was true for the late 5.0 roller blocks, so far I've seen 2 casting numbers for these, E6SE and E7TE, but they can be found in any 5.0 application, be it car or truck or van.
 
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asiantony

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Oct 1, 2005
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Jul 17, 2006
#7
  • Jul 17, 2006
  • #7
well, i've got a 1966 fastback with a 289. not sure if it's the original engine, but more than likely it is. how important is it to preserve the original engine? i really feel the need for a 347 stroker.
 
D

D.Hearne

New Member
Sep 29, 2000
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Jul 17, 2006
#8
  • Jul 17, 2006
  • #8
Well if you want top dollar for the car, it might pay to button up the 289 to keep the critters out and store it. Get a roller block for the 347.
 

BarnStang

Founding Member
Mar 2, 2001
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Hagerstown, MD
Jul 17, 2006
#9
  • Jul 17, 2006
  • #9
D.Hearne said:
The product line the block was cast for means nothing. I don't believe there's any "Z" coded blocks in 289's. They're all either "O" or "A" in the third character. Just because the third character denotes one vehicle, doesn't mean that's the vehicle it was installed in. That's the case maybe half the time. Ford never cast one particular engine block for one particular car. Take for instance the 428 CJ, the block casting numbers says it's a Mercury block, but there were more of these engines put into Stangs than Mercs. Same was true for the late 5.0 roller blocks, so far I've seen 2 casting numbers for these, E6SE and E7TE, but they can be found in any 5.0 application, be it car or truck or van.
Click to expand...

Means nothing? Pretty harsh even if true. I think I conveyed that the info I provided was not reliable. I was just trying to provide the guy some info-which is what he asked for. Not everyone will have a perfect answer all the time. No reason to dump on them...oh, I have seen a CZ block. My boss has a hi-po block in cold storage. THey are few and far between.
 
D

D.Hearne

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Jul 18, 2006
#10
  • Jul 18, 2006
  • #10
I didn't mean for it to sound harsh. You took that the wrong way. It's just that many seem to think the product line code means that a block cast for say, the Galaxie line would only be found in a Galaxie. And yea, the Boss block would be an exception, I thought about that afterward. But a Boss 302 block wasn't cast for a 289. It was cast for the Stang line, but not for 289's.
 
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