350 Casting Numbers

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Marcus

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So I’ve got the engine out finally and still have a ton of cleaning to do on it but am trying to figure out just exactly what year this thing is. Only numbers I’ve found so far is behind the flywheel. would any of the numbers there tell me when this block was made?
 

legopnuematic

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underneath where the alternator is there is a pad that has all that info stamped, provided that the block has not been decked
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Marcus

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Okay. Thanks. I’ve got a lot of cleaning to do before I can see that lol
 

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Okay so I’ve tried to decode this thing and since I can’t find anything online, what year was this block built? I was able to find out it was built in Flint but that’s about it. It has factory 2bbl and smog crap so I’m guessing it’s an 83 model but I don’t know everything.

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Marcus

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Okay so I’ve tried to decode this thing and since I can’t find anything online, what year was this block built? I was able to find out it was built in Flint but that’s about it. It has factory 2bbl and smog crap so I’m guessing it’s an 83 model but I don’t know everything.
 

Marcus

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Sorry phone issues and posted it more than once for some reason
 

omillan99

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Not sure if yours has it but on the rear drivers side where the bell housing mates to the engine. It wont give you an exact date it was made but it can tell you a range of years.

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Okay I’ll clean that up and look.
 

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Not sure if yours has it but on the rear drivers side where the bell housing mates to the engine. It wont give you an exact date it was made but it can tell you a range of years.

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3970010 Is the number on drivers side rear like you said. There’s also another stamped on it back there as well. It’s J214
 

Marcus

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Not sure if yours has it but on the rear drivers side where the bell housing mates to the engine. It wont give you an exact date it was made but it can tell you a range of years.

You must be registered for see images attach



Okay so I finally found the info I needed. It’s a 1974 model engine that originally came with a 4bbl and a t400 police behind it.
 
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Marcus

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underneath where the alternator is there is a pad that has all that info stamped, provided that the block has not been decked
You must be registered for see images attach



In this thread is the picture of the stamped numbers on mine in this spot. I know what part of it is but cannot figure out how to decode the number to the left to narrow it down as to what it came out of originally. Please help if you can
 

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legopnuematic

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It appears to be a 1975 Chevy that was built in Saint Louis. Which makes sense as the engine was made on October 23 1974 (going from the CMJ suffix) in Flint. Which does work with the Casting date J214, as that would be October 21 1974. As the block would be cast first, then assembled, stamped on the 23rd which would be late enough in the year to be in a 75 model year Chevy
 

Marcus

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It appears to be a 1975 Chevy that was built in Saint Louis. Which makes sense as the engine was made on October 23 1974 (going from the CMJ suffix) in Flint. Which does work with the Casting date J214, as that would be October 21 1974. As the block would be cast first, then assembled, stamped on the 23rd which would be late enough in the year to be in a 75 model year Chevy



Okay so why is that every site I’ve been on, the CMJ code says 1974 full size with the t400 police transmission? I’d like to have all the information/charts to be able to learn all of this. I can’t make any sense at all of the info on nastyz28 or the other site I found. There’s one site that has the casting numbers listed along with other numbers that also say it was in a 1974 full size with the t400 police. I’m not understanding how two or three could be saying different things
 
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omillan99

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What is getting you confused? What other information are you looking for? What other information are you finding? The info you are putting about the 1974 full sized with a t400 police is what I find all over. Since it was cast and assembled at the end of October it would go for the next model year just as @legopnuematic stated.
 

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