1969 Block Casting Date

[Jim Ellis]

Can anyone shed some light on the meaning of the casting date of M27 on a
1969 engine block. The engine assy stamping is V0924 HZ. Block casting number
3932386. Body build date of car CO4. A very early 69.

Thank You

[Terry M.]

Re: 1969 Block Casting Date

A story on that very subject in the Corvette Restorer. From the index search on this site:

M WAS FOR MYSTERY SPRING 01 ENGINE CODES

[Jim Ellis]

Re: 1969 Block Casting Date

I don't have that copy of the Restorer. Can you give me the high lights of the article, as far as the meaning of the M in the casting date.

Thank You

[Dan Pepper]

Re: 1969 Block Casting Date

Jim,

I too have an "M" casting date on my '69 L46 coupe (M48, to be exact). This is an October built car, 1004HW code, ser#32444. Per the article previously mentioned (Article titled, "M" is for Mystery), our engine casings were "experimental" castings that the foundry used to determine better casting methods. These were poured in batches of 50. After inspecting the cases and determining the new process worked as the engineers had anticipated, the remaining casings were released to the line. Some of each run were cut to pieces to inspect the casting. The runs using methods that didn't work were destroyed. From what I can tell, there have been only a handful of these castings discussed and/or recorded with NCRS, so they appear to be fairly rare.

[Jim Ellis]

Re: 1969 Block Casting Date

How is the N.C.R.S. handling the M code for the casting date on 69 cars that
are being flight judged.

Thank You

Jim

[Terry M.]