010 block has been refaced - how can I tell

[opelitis1]

Good morning!!!  Came across a 3970010 4 bolt main block that has been re-faced and in doing so has erased the original suffix coding and in its place is now hand punched  "302ci" by a machine shop or whomever???  On the rear of the block beside the 3970010 is a K 2 GM punch.  Lotsa paint back here and lighting was kinda marginal...  Beneath timing cover are punched  010 and 5F9 codes ..
Where else on this block can I look (peer) to find out if this an 010 1969 Z/28 block??? Thanks!! T.

[JohnZ]

There's no such thing as a "Z/28 block". Z/28's used the same block that was used in millions of cars and trucks, and there was no difference in the casting or machining. The only thing that made it a "DZ" block was the internals that were installed in it (crank, rods, pistons, cam) and the "DZ" suffix on the front pad stamp that identified its usage.

[opelitis1]

Hi John!!!  What do the 5F 9  and 010 codes de-note beneath the timing cover represent?  Is there supposed to be a VIN number GM stamped somewhere on the block, such, as the oil filter pad or beneath the starter mount housing??
Again, as the block has been re-faced, the suffix code is  gone..  I will double check the casting date near 3970010 as, K 2 can't be right...

[JohnZ]

Hi John!!!  What do the 5F 9  and 010 codes de-note beneath the timing cover represent?  Is there supposed to be a VIN number GM stamped somewhere on the block, such, as the oil filter pad or beneath the starter mount housing??
Again, as the block has been re-faced, the suffix code is  gone..  I will double check the casting date near 3970010 as, K 2 can't be right...

The 5F9 and 010 are foundry pattern identifiers. The original VIN derivative stamp would have been either on the front pad or on the vertical as-cast surface above and to the rear of the oil filter protrusion. The block casting date is on the rear flange, about 4-6 inches toward the passenger side from the distributor (opposite side from the casting number).

[opelitis1]

I'll get rid of the layers of paint near the oil filter pad and have a gander...  I have another block that has numbers on the starter block mounting area that is very close to the suffix number...  Is this number punched only on CE 402 blocks???   
What are foundry patten identifiers???  How did they know that certain blocks had a higher nickel content than the normal non marked 010 units?  It would be interesting to know exactly what happened back in say, 67 - 69 re. the process of ordering a '69 Z28 Camaro from a dealer and what steps GM took to ensure the customer received exactly what he ordered...
Computers were not as sophisticated as they are today so how in the heck was this accomplished using keypunch cards, this certainly was not an un-complicated process.
How did they know when to add more nickel to a certain number of blocks duting the pouring process? Were ther lists that came out with certain engines receiving certain VINS peculiar to a certain car???  I could go on and on with the questions.  Has someone penned a book of facts on this??? 

[JohnZ]

Many different "CE" blocks had a date code stamped on the starter mounting pad.

Don't confuse the "010" pattern ID (which identifies a foundry pattern piece for a 3970010 block) with the "010-020" raised numbers that indicate the 0.1% and 0.2% tin and nickel content in some blocks; that was an extended tryout where the added tin was to improve machinability and the added nickel was to improve bore wear. It was discontinued when the promised warranty improvements failed to appear, and the added cost was no longer justified. The "010-020" blocks weren't tied to any particular usage - the foundry had no idea whether any 3970010 block was going into a car, truck, marine engine, or any other usage, and the engine plant had no clue about the VIN of any car an engine would end up in. Both foundries produced 300 block castings per hour, and both engine plants produced 300 engines per hour; nobody kept any "lists".

[opelitis1]

I can't for the life of me envision how this manufacturing process worked without having to "halt the line" every minute... The enormity of it.. Piecework at an all-time high, I guess.  Again, question begs, what happened after the customer signed the sale papers saying he wanted a '69 Z..  Gotta remember, we are back in the 'ole days with minimal computers and communication was possibly by teletype machine..  What actually happened to get the customer the car the way he wanted when he signed on the "dotted line". 
Sorry to be such a "bug-bear" but this process is interesting, from the start to finish when the happy customer finally gets a glimpse of his '69 Z for the first time..  It must've been one heck of a process???   Ted

[JohnZ]

Read this:


   http://www.camaros.org/assemblyprocess.shtml

[opelitis1]

Thanks John!!! 
Ted