Decoding block stamped serial numbers. V0507ZAC
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Decoding block stamped serial numbers. V0507ZAC
Hello C4 tech club
I want to find out what an engine stamped with : V0507ZAC
is, and what it came in.
I understand the V means it was made in Flint.
0507 means it was cast May 7th.
Does any one know what the ZAC means?
It is an LT-1, cast iron block, aluminum heads, but what year is it, and was it in a Corvette with 4bolt mains, or is it out of an F body, or Impala or Roadmaster with 2 bolt mains and lower rated horsepower?
Thank you
I want to find out what an engine stamped with : V0507ZAC
is, and what it came in.
I understand the V means it was made in Flint.
0507 means it was cast May 7th.
Does any one know what the ZAC means?
It is an LT-1, cast iron block, aluminum heads, but what year is it, and was it in a Corvette with 4bolt mains, or is it out of an F body, or Impala or Roadmaster with 2 bolt mains and lower rated horsepower?
Thank you
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It was assembled on May 07. The casting date is on the rear bellhousing flange. If you want to be sure it was installed in a Corvette, the partial VIN is on a machined pad on the drivers side rear of the block, above the oil flilter, inline with the upper bellhousing bolt. Something like "N51xxxxx" where N is the year 1992, 5 is Bowling Green assembly plant (Corvette), 1 is car line identifier for that plant (ZR1 is a 5) and the xx,xxx is the sequential number beginning at 00,001.
NOT QUITE RIGHT -
NINE DIGIT EXPLANATION
I believe that a ZAC in '92 would be an A4 - NOT an M6
Last edited by WVZR-1; May 4, 2020 at 09:03 PM.
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Yes, the"last 6" is the sequential number. But what the first digit of that last-6 is, denotes which carline for that plant, the sequence belongs to.
The "last 9" is unique for every car produced by GM. None of the first 8 digits are necessary to identify one particular unit. In the parts system query system the last nine begin with the check digit. I sometimes forget about the leading manufacturer digit (which is different than the check digit in the VIN) on engines,. On some engines it can be a T for Truck. The last 6 are the plant sequential number, but the leading position of the sequence number (12th in the VIN) is the carline identifier. If there is only one carline produced at that plant, this will be a "1". If there are more than one carline at the plant in the same model year, it will be something else. In the C4 era, the ZR-1 has its own sequence, so the 12th is a 5. The next 5 are the sequential number 00,001-99,999. If production exceeds 100,000 for the model year the leading digit increments by 1. Ie, the last 9 of 1992 LT1 Corvette #100,000 would be 1N5200000. An XLR is a 6 in the 12th position.
I didn't post ZAC as a manual trans. I didn't check it. But I agree, my black book says ZAC is an automatic. (I refuse to use "A4" and M6" to denote transmissions in 25-35 year old Corvettes. In the years C4 Corvettes were produced, an "A4" is an Audi, and an "M6" is a pretty special BMW.).
The "last 9" is unique for every car produced by GM. None of the first 8 digits are necessary to identify one particular unit. In the parts system query system the last nine begin with the check digit. I sometimes forget about the leading manufacturer digit (which is different than the check digit in the VIN) on engines,. On some engines it can be a T for Truck. The last 6 are the plant sequential number, but the leading position of the sequence number (12th in the VIN) is the carline identifier. If there is only one carline produced at that plant, this will be a "1". If there are more than one carline at the plant in the same model year, it will be something else. In the C4 era, the ZR-1 has its own sequence, so the 12th is a 5. The next 5 are the sequential number 00,001-99,999. If production exceeds 100,000 for the model year the leading digit increments by 1. Ie, the last 9 of 1992 LT1 Corvette #100,000 would be 1N5200000. An XLR is a 6 in the 12th position.
I didn't post ZAC as a manual trans. I didn't check it. But I agree, my black book says ZAC is an automatic. (I refuse to use "A4" and M6" to denote transmissions in 25-35 year old Corvettes. In the years C4 Corvettes were produced, an "A4" is an Audi, and an "M6" is a pretty special BMW.).
The first digit is car-line (1) Chevrolet, (2) Pontiac, (3) Oldsmobile - you should catch on!! The 'last eight' of the partial will 'always' match the last 8 of the actual VIN. The rest of your comment I quoted is BS! What has an XLR have to do with any of the 'actual fact/description' of a GM partial/ NONE. My 'NINE DIGIT' explanation is directly from a GM FSM!
Adding the rest of the BS to your latest post explains I guess how little you understand. You did I'd say 'NOTHING' to actually help the OP!!
Why mention Audi & BMW? Refuse what you like!!!
*****You should have/could have stopped after the May 07 and considered your post 'factual'!!!
Last edited by WVZR-1; May 4, 2020 at 10:35 PM.
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Here is a clarification: These are both 1992 Corvettes:
1N5100400
1N5500400
Note the only difference is the digit after the assembly plant. The first number is for 1992 Corvette Base #400. The second number is for ZR-1 #400. I realize the last 6 are called "sequence number", but if you didn't know about the carline deal, (the 12th in the VIN) you wouldn't know what the difference in the two examples I cited is.
.
1N5100400
1N5500400
Note the only difference is the digit after the assembly plant. The first number is for 1992 Corvette Base #400. The second number is for ZR-1 #400. I realize the last 6 are called "sequence number", but if you didn't know about the carline deal, (the 12th in the VIN) you wouldn't know what the difference in the two examples I cited is.
.
Here's a random '90 and the partial would be 1L5802944
1G1YZ23J9L5802944
Last edited by WVZR-1; May 4, 2020 at 11:00 PM.
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