Team Chevelle banner

Date code timing

6262 Views 14 Replies 9 Participants Last post by  CRUSHBOX
What was the typical date code timing in 1972 between the block date code and date of the cowl? Is it normally weeks, months? More specifically, for a 1972 Chevelle SS 454 Convertible with an 05C 1972 build date.

How about between the Block, Heads, Exhaust and Intake manifolds?
1 - 15 of 15 Posts
I will go by how NCRS for corvettes go. they should be within a week. but will aslo alow the engine to be date coded 6 months poir to the cars build date. I am not sure if that goes for Chevelles but I can't see how the could be too driffrent
skryla, are you talking about the casting date of the block or the build date. The casting date will and should precede the engine assembly/build date. On Corvette's, the casting date should not precede the assemble date by more then six months. The engine build/assembly date should precede the car assembly date. On my plastic car, the block was cast December 29th, 1966, assembled in Flint on April 6th, 1967, and installed in the AO Smith body sometime around April 17th, 1967.
Sorry guys, I guess I wasn't quite clear. I want to know by how much time the block date code should precede the car build date.

An then, the normal progression and time lapse (if any) for the block, head and manifold codes.
My 71 SS454's block was cast March 30, 1970, Heads cast June 23, 1970, motor assembed July 30, 1970 and car build date of Aug 23, 1970 (in Canada).
I hope this time line helps.
i actually have spent quite a bit of time looking into this exact thing. as far as block/ heads/ intake/ etc... casting dates vs. car assem date on the cowl, in my opinion, most folks are too liberal. my '68 which i know to be correct from the car's history and not "put back together", the dates are as follows; block B10, heads B21, intake B20; my car reads 03A on the cowl. so as you see, these are all within a month. also, the transmission, flywheel, exhaust manifolds were all within 6 weeks of the assem date. i have a friend who for two years was in the muscle car salvage biz and he said from looking at cars he knows have not been restamped/ altered (4 door granny cars) that many cars had blocks cast around 2-3 weeks before the assembly date and almost all were within 4-5 weeks. so, while anything could happen, i would be somewhat suspicious if a car's casting dates were months before the assembly date. not to say the cars described in the other postings above aren't legit, i'm sure they are, but i think they would be kind of the exception.
See less See more
It would depend on the quanity of engines ordered etc.

Some engines were not in high demand and Chevy would often delay production on those till enough orders were received so the engine plant could schedule production. They could built over 100 engines per hour so they may have preferred to wait for enough orders.

So some of the lower production engines are going to have a longer span than run-of-the-mill engines like 283, 327, 350, base 396 etc. which were in mass produced. L78's etc would examples of low orders and might span a longer time as the assembly plant waited for enough orders to build them.
that all makes sense el camino. keep in mind my friend was looking at run of the mill stuff 90% of the time. my car is just a 325HP version which would be fairly 'mass produced' and might explain why all dates are so close to assembly. rest assured though that GM didn't want to waste money by inventorying engines for months in advance. so i'd say they made efforts to shorten the times between casting and when they were put into a car. at the same time, it makes sense that low production cars like corvette or low production engines like LS6's would be a greater time span.
But if you have 15000 engines produced but only 5000 orders for cars scattered over the model year, some engines probably did sit on the rack at the assembly plant waiting

The engine plant assembled in batchs, meaning they did not build 1 at a time. With 2 assembly line turning out over 100 engine per hour, Back in those days the concept of "just in time" inventory was not a practice. I have seen old photos of the final assembly plants with thousands of engine in racks
i'm not arguing with you elcamino, it sounds like you used to work for GM or something years ago before i was even born. i'm agreeing that in some situations engines probably sat around for months. this very question was raised in another tech forum and the consensus was that in the vast majority of cases, engines are cast within 4-5 weeks of car assem date. and i have much anicdotal evidence that this was in fact the case. i assume skryla is not asking about the 'exceptions' more the 'rule'.
Same here, not arguing but pointing out another point of view that hase been shown to be the case on some high performace models. There are many documented cases of long time spans from engine casting date to engine build date and to car assembly data.

I never worked for GM but I stayed in a Holiday Inn once.


The casting, machining and engine assembly was all done in one complex. Tonwanda NY for all big block, Flint, MI and St Catherines, ON PQ for small blocks and another engine plant in Flint the built only in-line 6 bangers. The engine plants shipped to assembly plant all across the US and Canada by rail.

Tonawanda and Flint V-8 each made around 5500 engines per day (one every twelve seconds)
FWIW my 70 SS 454 has the following dates, Block Oct. 69, Heads Jan 70 Carb Dec 69 all other small pieces Feb Mar. assembly date 4-14-70. Tranny is Apr.,Rear-end is Dec. 69. Build date for the car is 05D 4th week of May at Arlington, and I have the documentation.
Engines aren't the only components that may sit around awhile before being used. I have numerous POPs for 67 and while most components (engine/trans/rear) are within a month or so of assembly there are some anomalies. Cases in point:
L79 Malibu assembled in Atlanta in December - engine is Nov 18, rear axle (3.07 w/metallic brakes) is Mar 16, and basic Muncie 4-spd is Aug 19.

L34 SS396 assembled in KC in January - engine is Sept 29, rear axle Jan 11 and Muncie is Jan 13.

Then there's very short turnarounds - my first 67 (L34 SS396)was built in KC in May, engine is May 1, rear axle is May 8, and Muncie is May 2.
Have to agree with Dale, my P.O.P. is listed on ChevelleStuff On The Web, and it's the 3rd example from Arlington. 250179
My car is a Kansas car, block ,cylynder heads and intake manifold are all "L 9" with a engine assembly date of 1st week of Janurary 1970. Car is a "C" third week of Janurary.
1 - 15 of 15 Posts
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.