engine number stamp on the block

Dr John OConnor PhD

Pimp juice a Hemi's best friend
Oct 31, 2020
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jonesville VA
number stamp on the block 5(U/0)3456U5- SECOND DIGIT IS U OR 0


Can you get a better photo?

Does the VIN on your dash end in 345605 ?
You have 2 threads about it now, makes it tough.

No partial VINs for '65 as stated in the other thread, but a clear photo of that pad would still help ID the newer engine.
It is cast into the block on the passenger side of the block. The engine size is cast into the block on the drivers side...

Small block date code.jpg
It looks like a VIN number, meaning it's 1968 or later, if I recall I read they didn't start stamping them with VIN's until after 1968. And yes that is going to be on the rear of the passenger side.

My 66 doesn't have a VIN, it only has the year/displacement stamping info stamped on a pad facing up near cylinder 1 towards the front of the engine on the passenger side as well.
Welcome to the world of partially-informative replies.
The number you posted is the partial VIN. It's the last 8 digits of the original host vehicle's VIN. The first digit indicated the year, the second indicated the plant the vehicle was manufactured at and the last 6 was the production sequence. Having a decent eye for poorly stamped Mopar numbers, that one might start with 3B, which would be a '73 engine installed into a vehicle produced at Dodge main.

However, there are other things that nail down the date. Look down behind the ignition coil from the top with a bright light. There's a pad on the block facing upward that contains more info. Once you scrape it off, you'll see a string of characters that resemble H225R 3018 1644. Your's will not be exactly the same but that's the format.

H225R...The letter is the year code. H would be 1973, G 1972 and so forth. 225 is the displacement, R is for regular fuel. The two pairs of 4 digits afterward are, in order, the 10,000 day calendar assembly date and then engine number produced that day. You can enter the 4 digit date code into an online decoder. They "might" be reversed between the pairs of numbers. There are no dates cast into the block on a Slant, that's V8 only. The 4-digit numbers cast there are not date codes. Last, it looks like the engine is wearing original Chrysler blue, so that's '70 up. Good luck.
EDIT: I just noticed cylinder head. That's a '75 and later head at least, so who knows until you find all the numbers.
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3B partial VIN, so it is from a 1973 model year car made at Hamtramck. Could be from an A or E-body.
TylerW nailed it, blue and peanut plug aint stock in a 65! ..but the plug wires may be 65.....