Casting date and engine assembly date for late 1969 big block

[Joseph W.]

I have done a search on this topic but wanted to get the opinions of the knowledgeable members that frequent the forum.

I recently purchased a 1969 L89 project car. I'll be posting that journey on here when I get a bit of time.

I have the POP and on the POP the engine assembly date is Oct 20, 1969
The trim tag build date is Oct 31, 1969
I have been looking for a date correct block and thought I had found one with a Sep 5 69 cast date. In my mind that would be perfect.
However, the engine rebuilder stated he would like to find a block closer to the build date.
I told him that I thought the standard bore 512 Sep. 5 block seemed perfect, no need to look.
Well, I got a call yesterday and was told he had found a block (standard bore) with a cast date of Oct 14 69
He said it was perfect and that I'd "never have to defend the car with the judges with this block".

My question is this: Is 6 days from cast to assembly to close?
He is adamant it isn't.

Thanks

[Owen L.]

Re: Casting date and engine assembly date for late 1969 big block

Here are the pertinents for my '72 LS-5. The casting dates for the block: D1272 (April 12th) and both heads D1172 (April 11th). Engine completion stamp is 0422 (April 22nd), so 9-10 days prior to assembly. The body build date is J02 (May 2nd), also a 10-day spread between it and the engine completion.

[Joseph W.]

Re: Casting date and engine assembly date for late 1969 big block

Thank you so much for that info!

So, 6 days is a bit less than your 9-10 days.
Anyone else with a 69 want to chime in?
I'm going to check my 71 BB

[David H.]

Re: Casting date and engine assembly date for late 1969 big block

Joseph

Familiarize yourself with Standard Deduction Guideline # 1 Engine Block Cylinder Cases. Part "B" states "within six (6) months prior to car build date". Typically a couple of weeks.

YMMV with C2 A.O. Smith bodies. (V.I.N. and Birthday Book are your friend)

Dave

[Joseph W.]

Re: Casting date and engine assembly date for late 1969 big block

My 1971 BB has a casting date of Jan 25. 71
Assembly date of Feb 17 71
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[Joe L.]

Re: Casting date and engine assembly date for late 1969 big block

I have done a search on this topic but wanted to get the opinions of the knowledgeable members that frequent the forum.

I recently purchased a 1969 L89 project car. I'll be posting that journey on here when I get a bit of time.

I have the POP and on the POP the engine assembly date is Oct 20, 1969
The trim tag build date is Oct 31, 1969
I have been looking for a date correct block and thought I had found one with a Sep 5 69 cast date. In my mind that would be perfect.
However, the engine rebuilder stated he would like to find a block closer to the build date.
I told him that I thought the standard bore 512 Sep. 5 block seemed perfect, no need to look.
Well, I got a call yesterday and was told he had found a block (standard bore) with a cast date of Oct 14 69
He said it was perfect and that I'd "never have to defend the car with the judges with this block".

My question is this: Is 6 days from cast to assembly to close?
He is adamant it isn't.

Thanks

Joseph------

The Tonawanda engine plant where big blocks were manufactured had a co-located cast iron foundry where the blocks, heads, and other parts were cast. So, it was very possible for there to be a short time frame between casting and machining/assembly.

However, I think that either of the blocks you described would be fine for your car. The fact is that both are well within the 6 month window allowed for judging purposes. The reason that window exists is because there could be that much time between engine build and car build.

I do not think that you would ever have to "defend" the casting or assembly dates of either block.

[Joseph W.]

Re: Casting date and engine assembly date for late 1969 big block

Thank you Joe!
As always, your advice is appreciated.

[Patrick B.]

[Mark F.]

Re: Casting date and engine assembly date for late 1969 big block

in line with what Patrick just said, my '67 BB was cast E 5 7 (May 5, 1967) and the Tonawanda Engine Assembly Date was June 8, 1967 (34 days).

[Joseph W.]

[Terry M.]

Re: Casting date and engine assembly date for late 1969 big block

What Joe L and Pat B have said is quite correct. You should also consider your relationship with your engine builder since either block date will work and no judge should question either date. Make your decision based on economics (cost of each block) and how much you value your relationship with the engine builder. Will he do the whole engine build or is he just sourcing the cylinder case? The answer to those questions should drive your decision.

FWIW: My 1969 L89 (with M40 which should not matter) was cast September 8, 1968 and assembled November 29, 1968. The fact that you are looking at a 512 block and mine is the earlier 3955270 block shouldn't matter either.

Best of luck with your build and decision.

[Mark F.]

Re: Casting date and engine assembly date for late 1969 big block

Hi Joseph,

I know nothing about '69 casting and subsequent engine production at Tonawanda, but having worked in automotive Casting and Engine Plants, I can't see those two processes really changing all that much over the years from '67 to '69 - short of new engine introductions, which I don't believe is relevant in this case.

Line speed (which controls production quantities) in casting plants is primarily controlled by melt temperatures; casting size and complexity; pouring speeds and subsequent TIME needed for castings to properly cool until they can hit the cope and drag mold separation and shake-out stations. Then they go off to further cleanup and rough machining (deburring) prior to transfer to the Engine Plant(s). Increasing line speed doesn't work in a casting plant (particularly for an engine block), so the only way you could have drastically increased casting quantities would have been to have a complete 2nd line casting the same parts. That's very expensive and I doubt the bean counters would do that just to have assembly dates close to casting dates . Plus, it looks like engine assembly is the critical path in the date sequencing - castings apparently were available on the same site, but assembling them across the way was taking longer - hence the date spread.

So, the same applies to the Engine Plants. You can't rush cylinder case broaching, machining; line boring; and subsequent assembly steps, etc. The only thing I can see that you could have done to shorten the days between casting and assembly would have been to have a complete 2nd engine building line assembling the the same engines side by side. If you were able to do that, you could theoretically shorten the time from a block casting rolling of the line to completed engines rolling off the line. Again, duplicating lines is very expensive (but I suppose it could have been warranted depending on sales demand).



Yes !
Although the majority of my buying from numerous Corvette vendors (NCRS member or not) has been pleasant and rewarding, I have had very rude vendor encounters as well, including at least one who is still an NCRS member.

One and done is the way I handled that. I'm the customer - treat me with respect just the way I treat you and you'll probably get my business.

Avoid those guys and enjoy your hobby !

Good luck !

[Edward C.]

[Owen L.]

Re: Casting date and engine assembly date for late 1969 big block

I have the POP and on the POP the engine assembly date is Oct 20, 1969
The trim tag build date is Oct 31, 1969

FWIW: My 1969 L89 (with M40 which should not matter) was cast September 8, 1968 and assembled November 29, 1968.

Terry, et. al.,
Did the '69 strike/model year extension have any bearing on the spread between casting and assembly for the fall '69 production? Joseph's got a car from the later part of the model year extension whereas everyone else seems to be citing dates from within a standard model year.

[Justin S.]

Re: Casting date and engine assembly date for late 1969 big block

Joseph,
What part of California are you located?