1970 block casting date

[Jeremy H.]

DId 010 BLOCKS dATED LATE 69 (FOR A FEb 1970 car ) use the letter M (december) for the date or did they stop with L ?

Jeremy Hedges
#31711

[Terry M.]

Re: 1970 block casting date

Stopped with L, but by February I would expect most, and maybe all, of the 1969 small blocks to be gone, but maybe not. My Jan 29 car has a Jan 7 cast block. I guess it would depend on when in February.

[Jeremy H.]

Re: 1970 block casting date

February 11 th car.

[Terry M.]

Re: 1970 block casting date

The small block casting dates I have collected for that day range from L239 to A190. I don't have all of the Corvettes built that day -- far far from it. That is why NCRS allows up to six months from the body build for dates.

[Jeremy H.]

Re: 1970 block casting date

So was L or M December in 1969?

[Roberto L.]

Re: 1970 block casting date

If I remember well my Feb 05 car has an A block (January)

Best regards

[Terry M.]

Re: 1970 block casting date

So was L or M December in 1969?

Please see post #2 Jeremy.

[Mike G.]

Re: 1970 block casting date

remember 70 was a labor strike year. they did not make the first 70 until janruary 1970. they probably had stock piles of parts by that time. they probably took whichever block they could get to first. my friend has an early march 454 car with a december block. my 70 is a late june and i have a early june block.

[Kenneth B.]

Re: 1970 block casting date

The small block casting dates I have collected for that day range from L239 to A190. I don't have all of the Corvettes built that day -- far far from it. That is why NCRS allows up to six months from the body build for dates.

My 1970 LT-1'S SN 3893 A 1 O,SN 5128 B 2 0.
I know JAN 1 is New YEARS day. Corvette is 19,000 mi car & Terry judged it years ago. BG &NCRS judged
KEN

[Philip C.]

Re: 1970 block casting date

DId 010 BLOCKS dATED LATE 69 (FOR A FEb 1970 car ) use the letter M (december) for the date or did they stop with L ?

Jeremy Hedges
#31711

Hi Jeremy in the book chevrolet by the # Al says; some 010 blocks have been verified with a dec. M month code its unknown why this was done. Phil 8063

[Terry M.]

Re: 1970 block casting date

Unfortunately Alan Colvin is wrong on that point. The M coded cylinder cases (and there are more than just the 3970010) are test deviations from the normal castings. While I was editor of The Restorer we published an article on what the M-code means, and it is NOT a date.

[Stephen L.]

Re: 1970 block casting date

fwiw - I have a 1970 LT1 - the build date is Feb 4 1970 - the casting date of the engine is L189 – Dec 18, 1969 - thanks, stephen

[John H.]

Re: 1970 block casting date

From our CRG (Camaro Research Group) site, www.camaros.org, courtesy of Mark Gorney, who did the research at Saginaw:

"M"-Coded Blocks
There is one exception to the normal block casting date convention that has been observed: some blocks have been seen with "M" cast codes. Research by the Saginaw Metal Casting Operations of GM Powertrain Division has found that these "M" codes are not date codes, but actually a foundry code used to indentify parts that were made to evaluate a casting process change. After evaluating the parts, the blocks would either be destroyed or released into production. There is no way to determine the date an "M"-coded block was poured."M"-Coded Blocks
There is one exception to the normal block casting date convention that has been observed: some blocks have been seen with "M" cast codes. Research by the Saginaw Metal Casting Operations of GM Powertrain Division has found that these "M" codes are not date codes, but actually a foundry code used to indentify parts that were made to evaluate a casting process change. After evaluating the parts, the blocks would either be destroyed or released into production. There is no way to determine the date an "M"-coded block was poured.

[James T.]

Re: 1970 block casting date

search the archives for the name 'gamache'.