Date Stamping Numbers
| V8 Engine Block Casting Month Codes | |||
| A - January | B - February | C - March | D - April |
| E - May | F - June | G - July | H - August |
| I - September | J - October | K - November | L - December |
Date codes are the letter, 1 or 2 digits for the day, and 1 digit for the year such as J 25 7 would be October 25, 1967.
The block casting number on small block and big block Chevy V8 motors is located on a ledge found at the rear of the block, most often on the driver's side. This ledge is below the deck of the block and the ledge forms the mating surface between the block and the transmission bellhousing.
Engine Assembly Date/Suffix
Code:
The engine assembly code looks similar to this T0601EG.
In this case the first letter "T" stands for an engine
factory Tonawanda, N.Y., either "F" or "V"
would indicate Flint, MI., "K" is used for McKinnon
Industries while "S" is used for Saginaw Service. The
next two digits stand for the month of the year. In this example "06"
or the sixth month, June. The "01" stands for the 1st
day of the month. Sometimes (but not always) the letter "I" is
substituted for the number "1".
vs.
So what do we have so far in this example? The motor was assembled at the Tonawanda factory on June 1st. The years are not given. What we have left is the "suffix code" which in this example is EG, a 1967 396cid with 325hp. Chevy used one to three letters of the alphabet to code the type of engine, transmission and vehicle into the suffix code. In later years, parts of the Vehicle Identification Number (VIN) were also added before or after the Engine Assembly Date/Suffix code. In that case you might see "T0601EG 6A174373" (on separate lines) stamped into the pad on the front passenger side of the block. In this example, 6A174373 decodes to 1966 Atlanta final assembly, and the last six digits of the VIN. Depending on the year and plant, the VIN could be stamped into a different area of the block; the flange edge of the rear of the block near the bellhousing mating surface, the rough cast area next to the oil filter and sometimes the stamping is found above the timing cover mating surface on the front of the block.
There is another type of stamping found on some blocks. This is the "CE" code. You might see something like this "CE056789" on the front pad of the block deck on the passenger side. The "CE" stands for "Chevrolet Engine" but is sometimes referred to as "Counter Engine", "Counter Exchange" and "Crate Engine" was used on blocks that were warranty replacement engines. If a customer had problems with his original engine, while it was under warranty, it was replaced with an engine that was stamped "CE" with a 6-digit number following it which serialized that particular engine. It's important to note that the "CE" designation for replacement Chevrolet engines did not start until 1968 so any year designation in the engine number would be for 1968 and later.
It is believed this method of identifying replacement engines stopped after the 1975 model year. This is supported by a notation in a 1976 dated Chevrolet parts book, "The engine plants are to stamp the serial pad of all current model service engines with the source, production date, and same type designation as stamped on a comparable production engine."
V8 Engine Block
Casting Numbers By Year (1964-1972)
Other references:
Blocks:
http://www.mortec.com/castnum.htm
http://www.mortec.com/bbc.htm
Heads:
http://www.mortec.com/castnum.htm
http://www.mortec.com/bbc.htm
