. Hang in there, if you try, you can use a mirror and a little patience for the hard to see and reach areas. The body of a Chevy is easily identifiable by shape, size and select characteristics. Identifying a Chevy big block engine based solely on the serial number is a straightforward task once the serial number is located and then deciphered. Although Chevelle engines were 2-bolt main blocks, there have been 4-bolt main versions of this block found. Casting date on the right lower side near the freeze plug in front of the starter.
It's reported that some early blocks have been found with three digits representing the month, day, and year. Bowtie, aluminum, 45cc chambers, 1st version, symmetrical ports, 263cc intake ports, splayed valves 10185040. . The casting numbers can be found on the rear drivers side flange that meets with the transmission bell housing. If you notice any mistakes or have any additions, use my form and let me know so I can update the list.
The casting number will not tell you the casting date. Has 'tall tower' distributor casting boss. Chevrolet had introduced its popular small-block V8 in 1955, but needed something larger to power the medium-duty trucks and its heavier cars that were on the drawing board. Everything else lines up and there's no confusion. That eliminates the 400 and 305 possibilities.
I, also used on crate motors, 285 or 300 hp, 64cc chambers, 72' center manifold bolt angles 14101128. Some of the early big blocks made in the Sixties have the block casting date located on the passenger side of the block near the freeze plug holes. . Camel hump,no accessory holes,64cc chamber 3917292. Roller or flat tappet cam, one-piece rear seal 14093638. I know Norwood built Camaros - among other things.
Look at the remaining portion of the code. The pointer indicates this block was cast in the 8th hour of the shift. Hey man - is this a 4 bolt main? On 300hp and above, they all have chamfered main bearings. Quickly from the partial vin I know this is a Chevy 1 1973 model year 3 built in Norwood Ohio N. Camel hump,64cc chambers,accessory holes 3927188.
Also trying to read them while the motor is in a vehicle can also be harder, especially the block casting numbers and casting dates at the rear of the block. Production of the original small-block began in the fall of 1954, for the 1955 model year, with a displacement of 265 cid, growing incrementally over time until reaching 400 cid in 1970. The small-block engine is a series of automobile V8 engines built by the Chevrolet Division of General Motors using the same basic, and for a V8, smaller engine block. Some casting dates have both the year of the decade and the decade itself. . Every hour the pointer would be moved clockwise to indicate the hour. The block casting date is usually found on the rear ledge of the block on the passenger side, but some later model blocks have the casting date on the driver's side of the rear ledge.
Big Block Chevy: Machined pad in front of the passenger side cylinder head or above timing chain cover. You can decode the casting number. In all, over 90,000,000 small-blocks have been built in carbureted and fuel injected forms since 1955. It should be noted that much earlier 427 and 454 engine blocks have been found with casting dates as early as September 5, 1969 in a 2-bolt configuration and several in the October timeframe in a 4-bolt configuration. All 3782870 blocks should have nodular bearing caps. And if you find our site helpful, please like us on Facebook! There are fascinating stories that explain everything from mid-year running changes to production idiosyncrasies. Casting date on the right lower side near the freeze plug in front of the starter.
Lots of information on Big block casting numbers can be found in this book. This block is known to have been installed in L78 applications; 325hp or 360hp applications are unsure. The 1989 Chevy Caprice came with 3 different engines. The matrix below is for Chevelle applications only although many were used in other makes of the Chevrolet Division. The 1989 Chevy Caprice came with 3 different engines.