The Engine Suffix Code is stamped on a block pad located immediately forward of the right hand or passenger side cylinder head picture here. The entire engine code contains the assembly plant, month (MM) and day (DD). See note below if your month or day code has a letter "I" instead of a number in it.
Engine Code Style Pre '70: F0114MB
|
F
|
01
|
14
|
MB
|
|
Assembly Plant |
Assembly Month (MM) | Assembly Day (DD) |
Suffix
|
Engine Code Style '70 on: F0114CMB
| F |
01 |
14 |
C |
MB |
| Assembly Plant |
Assembly Month (MM) | Assembly Day (DD) | Motor Division | |
Suffix |
||||
Note: Some don't have a motor division for example.
| F |
01 |
14 |
UAF |
| Assembly Plant |
Assembly Month (MM) | Assembly Day (DD) | Suffix |
Note about the letter "I" instead of a number "1" in the engine code for the date: Sometimes the number "1" looks like the letter "I" for the date codes. It is still a date code. All date codes are two digits, always, so if it looks like the letter "I" it is still the number "1". For example the actual stamped code may be "F0II4MB" but it really is "F0114MB".
| Engine Assembly Plant Codes: | Motor Division: | |
| F - Flint Motor Plant | C - Chevrolet passenger car | |
| K - McKinnon | T - Chevrolet truck | |
| M - GM of Mexico | ||
| S - Signaw Service | ||
| T - Tonawanda Engine Plant | ||
| V - Flint Engine Plant |
Close to the engine suffix code is the partial VIN code. Partial VIN example:
"18U199887" decodes as "1"=Chevy, "8"=1968,
"U"=Vehicle assembly plant Lordstown, Ohio and "199887"=last
six digits of VIN.
| VIN Assembly Plant Codes: | (Continued) |
|
| A - Atlanta, Georgia | R - Arlington, Texas | |
| B - Baltimore, Maryland | S - St. Louis, Missouri | |
| C - Southgate, California | T - Tarrytown, New York | |
| C - Atlanta, Georgia (Doraville) ('64 only) | U - Lordstown, Ohio | |
| D - Atlanta, Georgia (Doraville) | U - Southgate, California ('64) | |
| F - Flint, Michigan | W - Willow Run, Michigan | |
| G - Framingham, Massachusetts | Y - Wilmington, Delaware | |
| H - Fremont, California ('64 only) | Z - Fremont, California | |
| J - Janesville, Wisconsin | 0 - Oshawa, Canada ('65-'69) | |
| K - Kansas City, Missouri | 1 - Oshawa, Canada ('70-) | |
| L - Los Angeles, California | 1 - St. Therese, Canada ('67-'69) | |
| N - Norwood, Ohio | 2 - St. Therese, Canada ('70-) | |
| O - Oakland, California |
Some of the Engine Suffix codes were used a number of times. For example suffix code "CMJ" was used in 1974 on a 350 and in 1980 on a 305. You need to look at the block casting date and casting number to narrow it down. Do not just rely on the suffix code to identify the original use of the block because it can be misleading in some cases. You should always look at ALL of the casting identifiers to determine exactly what engine you have.
"CE" or Crate engine information: CE123456
| CE |
123456 |
| Crate Engine |
Serial Number |
Another type of stamping found on some blocks is the "CE" code. You might see something like this "CE123456" on the front pad of the block deck on the passenger side. The "CE" which has been known to stand for "Chevrolet Engine" or "Crate Engine" was used on blocks that were warranty replacement motors. The "CE" prefix was also used on "over the counter" blocks and engines. If a customer had problems with their original engine, while it was under warranty, it would have been replaced with an engine that was stamped "CE" with a number following it. The number following the "CE" code was the serial number for that particular engine. Also if someone purchased a new motor from the Chevrolet Parts counter, the front pad on the passenger side of the block may have been stamped with a "CE" code.
A number of crate motors made by GM in Mexico, may have an "M" or "ML" prefix stamped into the front pad of the block followed by a series of numbers which is the serial number of that particular crate replacement motor. You may also see a raised casting on the block or heads of "Hecho en Mexico" which means "Made in Mexico". Many of the new GM crate motors are being made in Mexico. Later model crate engines, sold over the counter by Chevrolet or GM Performance Parts, may have different prefix code identifiers stamped in to the front pad on the block, such as "ZZ3" or three letter codes such as "XXA".
Other things to watch out for when decoding an engine block. If the block has previously been decked by a machine shop the engine assembly date and suffix codes may have been removed by the machining process. They are gone but they can possibly be retrieved, just not easily. If you are interested and very desperate you can read our FAQ information on possible ways to retrieve a removed engine code. Some blocks have been re-stamped in order to create a "numbers matching" vehicle. With the increase in value of many "numbers matching" collector cars, some folks have restamped the blocks to deceive buyers. Again the original engine code can possibly be retrieved. However, be sure to check all numbers including the casting number and date code on the back of the block. Those can help determine whether the engine date is appropriate for the vehicle production date. If something doesn't look correct then it's not.
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