1970 Big Block decoding
Thread Starter
Racer
Joined: Sep 2004
Posts: 497
Likes: 0
1970 Big Block decoding
Okay my back is broken and my eyes are getting old like me.
I have the numbers on my block
casting # 3965312
"K" Hi Perf Pass
with a L 15 9 as casting date
Engine ID # T1219CZU 405401451
The T1219CZU does it mean anything?
I can match up the 401451 with the numbers on my VIN on the pillar post. but that first three numbers 405 doesn't make sense. Anyone know?
These are all the numbers I found so far.. and feeling like Sherlock Holmes now. LOL
I have the numbers on my block
casting # 3965312
"K" Hi Perf Pass
with a L 15 9 as casting date
Engine ID # T1219CZU 405401451
The T1219CZU does it mean anything?
I can match up the 401451 with the numbers on my VIN on the pillar post. but that first three numbers 405 doesn't make sense. Anyone know?
These are all the numbers I found so far.. and feeling like Sherlock Holmes now. LOL
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Melting Slicks
Joined: May 2009
Posts: 3,079
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2024 C3 of the Year Finalist - Unmodified
The block number is surely 3963512, not 3965312 as you posted. The casting date of L 15 9 is December 15, 1969...just 4 days before the assembly date. Them Tonawanda guys didn't even hardly let the block cool off before slapping it together....
Thread Starter
Racer
Joined: Sep 2004
Posts: 497
Likes: 0
Okay not only am I getting old and white hair came yrs ago.
I'm deslectic and can't even write numbers down in thier proper sequence.
To correct the Block number is 3963512
and checked again the number on the ID which is 70S401451
Thank goodness. (Couple of Hail Marys)
How in the heck did I put down 405 is beyond me.. The "5" okay I can live with but the "4" no... I need stronger glasses. LOL
So Joe Will & Faster Rat.. That Dec 15, 1969 casting date which is 4 days before the assembly date.. Is that normal? I guess they needed a couple of days for the Iron Block to cool off Harden and chill with some brewskies. LOL
Thanks for all your help guys!!
I'm deslectic and can't even write numbers down in thier proper sequence.
To correct the Block number is 3963512
and checked again the number on the ID which is 70S401451
Thank goodness. (Couple of Hail Marys)
How in the heck did I put down 405 is beyond me.. The "5" okay I can live with but the "4" no... I need stronger glasses. LOL
So Joe Will & Faster Rat.. That Dec 15, 1969 casting date which is 4 days before the assembly date.. Is that normal? I guess they needed a couple of days for the Iron Block to cool off Harden and chill with some brewskies. LOL
Thanks for all your help guys!!
Thread Starter
Racer
Joined: Sep 2004
Posts: 497
Likes: 0
Mike.. LOL OMG... Please I apologize.. Seriously.. I've seen even in the past you helped me out with other inquiries I needed answers to, and you've helped a tonne of people here.
I'm a lazy guy as I posted the last two names in my response and should have included all.
See! Now I'm going senial! LOL..
Thanks for your info Mike, and when you come to visit T.O let me know
I'm a lazy guy as I posted the last two names in my response and should have included all.
See! Now I'm going senial! LOL..
Thanks for your info Mike, and when you come to visit T.O let me know
Team Owner
Joined: Jun 2000
Posts: 38,923
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From: Southbound
Cruise-In II Veteran
My 327 was cast on April 3rd; the engine was assembled on April 9th. Four working days considering there was a weekend between the two dates.
Remember: GM had an order for a new big block Corvette; before they scheduled assembly of the car, they ordered the engine from Tonawanda. The foundry got the order and poured what was to become your block on December 19th.
Remember: GM had an order for a new big block Corvette; before they scheduled assembly of the car, they ordered the engine from Tonawanda. The foundry got the order and poured what was to become your block on December 19th.
Last edited by Easy Mike; Nov 4, 2010 at 09:43 AM.
