engine numbers : small block chevy


The Engine Numbers on a small block chevy.

The following diagram and text was taken from: http://www.mortec.com at their CHEVY V-8 CASTING NUMBER LOCATIONS page of their website. I’m just giving credit where it is due. They have LOTS of information on their website about head numbers, block numbers, etc., so if you are looking for that kind of information, go check them out.

NOTE: 06/2012 : The mortec site does not load up anymore, but that is where I found this information.

UPDATE: 02/02/2013 : the Internet Archive “wayback machine” has an archive of the Mortec site. Go to the site, look for the Wayback Machine and enter in the mortec.com URL. Lots of good information there folks! Thanks to the folks at the Internet Archive!

UPDATE : 05/2015 : looks like the mortec.com URL has a site back up again… new format but lots of great information still… so go explore.

The diagram above shows where each of the casting identifiers is located on the engine.

(1) shows the location of the HEAD CASTING NUMBERS and the HEAD CASTING DATE located under the valve covers, in the rocker arm valley.

(2) shows the position of the BLOCK CASTING DATE on the rear ledge of the block near the bell housing mounting surface. If you have an early big block or a late model smallblock, the BLOCK CASTING DATE may be on the passenger side of the engine block, (see 2A), instead of the rear ledge of the block. Some smallblock blocks may also have the BLOCK CASTING DATE on the driver’s side of the block.

(3) indicates the position of the BLOCK CASTING NUMBER. Later blocks may also have the size of the engine displacement in liters listed at (3).

(4) indicates the position of the ENGINE ASSEMBLY DATE/SUFFIX CODE and partial VIN code information on the front of the block.

for instance, on my engine block it is: K0309TPA

“tonypirate” of the forums at Full Size Chevy deciphered the above number and gave me the following information: for the suffix K-Canada the 0309 is the assembly month then the day TPA part of the suffix: truck / 1992 / 350cid / 210 hp / manual trans / RPO# L-05 / TBI vin K .

Thanks again tonypirate!

(5) on the rear flange of the block, on the drivers side near the oil filter pad, is an alternate block location for some VIN codes.

(6) indicates the sides of the block where some blocks may have the size of the motor indicated in cubic inches or in liters. The last three numbers of the block casting number may also be repeated in this location.