casting number question

[cdg1984]

On the rear of the block on the driver side, right by the bellhousing, i found the casting number 3970010, which I found is eitehr a 327 or 350. On the same side, right above that number, it says 38 GM. Then, a little to the right, it reads T D Z, in a circular pattern. I cant find any info on these numbers, anyone know anything? Thanks.

 

[hurst1979olds]

What year is the block. Near the casting number should be a date code. It'll say something like B182 for an 010 block that would be February 18, 1972. The 010 block was built from 69-79. But only year as a 327 was 68.

 

[cdg1984]

Yeah that was going to be my next question. I was under the impression that the casting date code was on the driver side near the casting number, but there is nothing there. However, on the passanger side rear block, below the distributor, is the code E137. Did some research and found that the E stands for the month, and the numbers the date and year. Did they put the code on the passanger side in some blocks?

 

[cdg1984]

So now I have the suffix code...txb. Txb is for a 75 year, but according to the date code, e137, its a 77. el confused-o. I have the partial vin also. Ive been searching for a site that I can run that number, but so far nothin. Can anyone help?

 

[art]

Actually your deck stamp is a three year stamp. See here:http://www.chevymania.com/partsid/suffixresults.cfm

 

[clean8485]

According to the information that I have here, the TXB suffix code translates to a '75-'77 350 165HP with auto trans & federal emissions in CK20-CK30 trucks, so what you have is probably the 1977 truck engine, which would match with your date code. Hope this helps.

 

[GhettoRacingKid]

is it a 4 bolt main?

under the timing cover what is stamped there? is you see 010/020 you got yourselve a killer block.

great block for a build up. nice and strong

 

[cdg1984]

Thanks guys. Ghettokid, im not sure about that. Is that the code for the high nickel block? I was thinking the high nickel were only made up until the early 70s, 77 may be too late, but hey I can hope! 🙂

 

[GhettoRacingKid]

Thanks guys. Ghettokid, im not sure about that. Is that the code for the high nickel block? I was thinking the high nickel were only made up until the early 70s, 77 may be too late, but hey I can hope! 🙂

not sure of the years of the blocks but always worth a look.

 

[art]

010 and 020 have to do with percentages of tin (1%)and nickle (2%)in the block. Acording to Dave Vizard, the tin helps the molten metal flow betterwhile casting , while the nickel work hardens and gives longer bore life. The blocks are least prone to cracking and because they pour more easily, they have the least problems with hot spots caused by porous metal.


Taken from Vizard's book " How to build max performance Chevy small blocks on a budget"