The vehicle identification number (VIN) is a unique combination of 17 letters and numbers that is assigned to a vehicle when it is built. Here's how to decode it. Aug 03, 2017  This is the Chevrolet VIN decoder. Every Chevrolet car has a unique identifier code called a VIN. This number contains vital information about the car, such as its manufacturer, year of production, the plant it was produced in, type of engine, model and more.

Chevy Small Block V8 Engine Identification

General Decoding Information
This topic can be somewhat confusing, especially with the amount of information available and the interpretation of it. The primary pieces of information you'll decode are the;

1. Engine Code and
2. Partial VIN.
3. Casting Date.
4. Casting Number.

The engine code and partial vin # will accurately nail down whatever the thing is rather quickly, and the other information will fall into line with that.

'Numbers Matching'
This is my opinion, and the generally accepted norm:
When people say 'It's numbers matching' - what they mean is the engine (or other component, i.e the transmission) can be MATCHED to the vehicle it was originally used in. This match is done via the PARTIAL VIN stamp on the component. The partial VIN will match the vehicles VIN. If it does - it's 'numbers matching', otherwise - it's not. done. end of story.
Some folks use these terms loosely, or will say 'numbers correct' or something to that effect. But numbers correct is not numbers matching. Again, it either matches or it doesn't. If it doesn't match - is it correct?
Numbers matching is important when you're trying to decode a Z28 or Super Sport where the VIN won't identify the vehicle as such. You need to decode the engine and see if it matches the vehicle, and if the code signifies Z28 or SS equipment.
Lastly, in extreme cases, you'll want to verify the numbers stamped onto the component were the ones stamped into it originally and aren't restamped.
The point of this page is to help you figure out how to decode stuff.

1. ENGINE CODE STAMPING NUMBER

All engines are stamped with an engine ID code, consisting of assembly plant code, production date and suffix code. V8 codes are stamped on a pad just forward of the right side (passenger) cylinder head.

The engine date must precede the car build date, otherwise something is amiss. Some engine machining operations (decking) will obliterate the engine ID.

Chevy Engine Serial Number Decoder List

Engine ID Code Example: V0101CLJ - (V = Plant, 01 = Month, 01 = Day, CLJ = Engine Suffix Code)
Another example: T0830CTY - (T = Tonawanda, 08 = August, 30 = 30th day, CTY = 1970 396 Camaro, 375 hp, 11.0:1, TH400)

Engine Plant Code

Engine Suffix Code

Suffix codes are either alphabetical or alphanumeric. Select the portion of the alphabet for your code. For example, select 'DTR-HQ' if you'd like to find code DZ. In some cases suffix codes are reused twice or more over time, in this event check the partial VIN code or block casting date code and then see what year the block was made to pin down what application your block was originally used in. This list of codes is a summarization, it is not complete nor all inclusive.

Small Block Engine Suffix Code Menu
3N - CDR | CE - CMJ | CMK - CUD | CUF - DTM |DTR - HQ | HR - TBS | TBT - TJS | TJT - TXB | TXC - UTT | UTU - ZY

Big Block Engine Suffix Code Menu
0FC - 9XZ | AAA - CTB | CTH - IJ | IK - MZ | Q - YZ

Note: CODE CExxxx (counter or crate engine) was used from 1968 to current year. It represents any CID and is used to indicate this particular engine was replaced under Warranty. It is a direct replacement for the original equipment. It doesn't indicate what the original equipment was.

VF292800 - is an example of a over the counter crate engine. '2800' is the last 4 digits of the GM part # for the crate engine assembly. The final digit could be a year code.
Another example: A Targetmaster engine (p/n 14009800) built in 1985 could have a code stamped as follows:
A0198005 (A = january, 01, 9800 = pn, 5 = 1985).

2. VIN CODE

VIN Code Format
The vin code format is stamped onto most engines. The format consists of divisional identification number, model year, assembly plant designation and vehicle serial or sequence number.
In 68-69 model cars, the serial (VIN) number of the car the engine was installed in is stamped next to, or under the engine code ID.
Starting in 1970, the serial number is stamped either above the oil filter, somewhere on the block pad (in front of the cylinder head), or on the transmission flange somewhere. Chevrolet issued technical service bulletins to indicate which engines were to recieve a vin stamp, so who knows what could have happend (or not happened).

VIN code format Example: 13N100001
(1 = Chevrolet, 3 = 1973, N = Norwood, 100001 = Production sequence of vehicle VIN)

Assembly Plants

In 1972, plant codes changed to reflect the VIN code. For example, 'NOR' = Norwood before 1972. In 1972 and on, it was simply 'N'.

3. CASTING DATE

Casting Clock
On some Saginaw blocks, intakes and exhausts a 'clock' was cast into the block. The clock is a circle of 10 dots, one dot for each hour of a shift (usually 10 hour shifts). An arrow points to the beginning of the shift an another dot outside the circle indicates what time of day the cast part was made. Anyways, that's what that circle thing is (if you happen to see it on something).

Casting Date
Small block casting date is located on driver side rear of block on flange forward of bellhousing. Big block on the right side of engine above the oil pan rails.

Casting Date Example: E038 - (E = Month, 03 = Day, 8 = Last digit of model year (1978)).

Month: A = Jan, B = Feb, C = Mar, D = Apr, E = May, F = Jun, G = July, H = Aug, I = Sep, J = Oct, K = Nov, L = Dec

4. ENGINE BLOCK CASTING NUMBER

Notes (for below): 'High Power' is the maximum rate HP this block was used for, 'Low Power' is the lowest rated horsepower RPO engine the block was used in. 'Main Caps' is the number of bolts holding the cap. A 'two-bolt' main, or a four-bolt main. Four bolt main blocks are desirable in high performance applications because the extra strength of the additional bolts keeps the bottom end rigid and less prone to failure. However, a properly prepared 2 bolt main engine will work just fine (often times you'll lose a rod bolt before you break a crank because it's 'only' a 2 bolt main).

General Engine Block Specifications

Absolutely! You can find out which type of engine was installed during the manufacture of a vehicle simply by using out free Chevy VIN decoder. Chevrolet Camaro? No problem. Chevrolet Caprice? We’ve got you covered. In fact, our free Chevy VIN decoder works for all models, including Corvette, Malibu, and Impala.

How do I read a Chevy’s VIN number?

We make it simple, so that you don’t have to read a vehicle’s VIN. Simply input your VIN into our free Chevy VIN decoder, and we’ll do the rest. You’ll find out a whole heap of information, including:

• Has the odometer ever been altered?
• Does the seller really own the car?
• Has the vehicle ever been totalled, flood-damaged, or salvaged?
• Has it ever been involved in an accident?
• Plus more information from public sources

Is There a Chevy VIN Decoder Chart for Trucks?

No, and with good reason. A Chevy truck VIN decoder chart would be so complicated—due to the sheer amount of trucks manufactured by Chevrolet—it would almost impossible to circumnavigate. This is why we offer our free Chevy VIN decoder, which will give you more information in just a few minutes than any complicated chart ever could.

Okay, So I Want to Buy a 1970s Chevy. Is There a VIN Decoder for That?

Chevy 235 Engine Serial Number Decoder

The 17-digit VIN number we use today came into play in 1980, which means that, unfortunately, we do not offer decoders for any vehicle post-1980.

Chevy Engine Serial Number Decoder Numbers

How Do I Read a Chevy’s VIN Number?

Unfortunately, we can’t teach you how to read a Chevy’s VIN number. Our free Chevy VIN decoder was created to make it as easy as possible for you. All you have to do is put your 17-digit VIN into our search engine, and we’ll do the rest. Trust us when we say it’s as easy as one, two, three!

What About a GMC VIN Decoder?

Chevy Engine Serial Lookup

Chevy Engine Identification Numbers Decoder

We have that too! Our Chevy VIN decoder works as a GMC VIN decoder, too, since they both utilise the modern 17-digit VIN system.