How to Tell the Year of a 454 Chevrolet Engineby Blaze Johnson
Starting in 1970, the 454 big-block V8 engine made its way into many Chevrolet-branded high-performance passenger cars. Due to the fuel crisis in 1973, the massive 454 was primarily offered in heavy-duty General Motors trucks from 1974 to 1996. Locating and deciphering your big block 454’s casting code will allow you to purchase replacement parts easier with regard to a restoration project, as well as confirm the engine is “number matched” to your vehicle.
Allow your engine to cool before searching for your engine date code. You will also need to obtain the casting number in addition to the date code on your big-block 454. This is because the casting code will allow you to determine the production decade, while the actual date code provides the month, day and only one number for identifying the production year.
Locate both the engine and date code on the top driver’s side of the bell housing flange (where the transmission mates to the engine). On some vehicles, you may need to open the hood and look down between the firewall and the back of the engine, while on other vehicles, it may be necessary to climb underneath the vehicle to gain visual access to the codes.
Clean off any dirt or debris from the bell housing with engine degreaser and a cotton rag if the engine/date codes are covered. The numbers “3”, “9”, “6” and “8” can be difficult to distinguish, so it is important to thoroughly clean these numbers off to obtain the correct codes.
Locate the first string of seven numbers and write them down on a piece of paper. These will be the engine’s casting numbers, and you will need to cross-reference them to obtain the correct production decade.
Write down the alphanumeric characters located toward the middle of the bell housing flange and remove any debris covering them with a rag and engine degreaser. The beginning letter of the date code will represent the month (the letter “A” would represent January, “B” for February and so on). The next two numbers will indicate the day of the month, while the last digit will tell you the year in which the engine was produced.
Items you will need
- Engine degreaser
- Cotton rag
- Small mirror
- Pen and paper
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