Casting/stamping numbers. What do your eyes see?

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demon322

demon322

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To me this casting date looks to be 1-18-71. My question is, why is the 1 in ‘71’ so different than the month and day? It looks much thicker and also a littler lower than the 7.

Also, the number stamped above the oil pan seems to be in a different format than what I have found so far online, but I could be wrong there also.

Thanks all!

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The day and month change a bit. The year casting sets for a while. The foundry guys likely didn't notice it shifted in the core box would be my bet. The car serial # looks like a double-strike, which seems to have happened a bit, just from my own observations over the years. YMMV
 
This makes sense, thanks.

So for the partial VIN, if I’m understanding correctly this block was in a 72 model car even though the block was cast in early 71 (which I understand was common as assembly usually happened much later than casting.)

Thank you both.
 
demon322 said:
This makes sense, thanks.

So for the partial VIN, if I’m understanding correctly this block was in a 72 model car even though the block was cast in early 71 (which I understand was common as assembly usually happened much later than casting.)

Thank you both.
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Yup. Happened all the time.
 
str12-340 said:
.040 over with a .010/.010 crank?
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Ah, that could be the case.

That has me concerned though, I had hoped to use this block for a planned stroker build, but most of the kits I see call for 30 over. If this block is already 40 over it may not be the best candidate. Won’t know for sure till it’s apart I know, but there may be better options it sounds like.
 
The casting date plate get's changed every day (obviously) See the screw heads between the numbers? They are screwed into the core when the numbers are changed. The individual number blocks are machined into the plates so the number comes out exposed above the surface. Sometimes the foundry sand breaks away or sticks to the numbers and the figures get deformed when the iron is poured. This is pretty normal for an iron foundry.
 
toolmanmike said:
The casting date plate get's changed every day (obviously) See the screw heads between the numbers? They are screwed into the core when the numbers are changed. The individual number blocks are machined into the plates so the number comes out exposed above the surface. Sometimes the foundry sand breaks away or sticks to the numbers and the figures get deformed when the iron is poured. This is pretty normal for an iron foundry.
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I did notice the screw heads! I guess I’d really never paid attention to them before on my other blocks. But this is a good explanation, thank you.
 
older 340s are pretty beefy, but you won't know unless you disassemble it and have the block tested
 
I can't say I've ever seen a 340 with a rebuilders tag before... I'd say to check and see if it is actually .040 over. Anything over that in a post 1970 casting tends to be a thinner casting, so a sonic check would be in order before going .060 over. If the bores still look good with no obvious ridges and it has cast pistons, then there may be enough material to "hone to round" for a forged piston.
 
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