Dodgeman, I have 2 A14's. One has H72 cast in the block and one has M72. I also have an A12 with H10. Any help??

Sorry my friend, but the only person that seems to have a handle on casting numbers on Datsun engine parts is in Japan right now. [Ddgonzal]
If it was a 50's era Hemi engine, then just give me any casting or forging number & I could help, but not with Datsuns unfortunately.

I don't know that Datsun ever made a crook version of any of the blocks, so just use the one that you like best & run with it.

Same with the A12's.
I sometimes wonder if there were several different foundries & some of the codes simply indicated which foundry it was cast at.

There seem to be quite a number of subtle variations in cylinder blocks & this one is a bit of a puzzle to me.



When the block was redesigned for the air conditioner mounting ['74 & on] they cast three mounting lugs on the crankcase & drilled two more holes on the thickened pan rail to take the mounting plate, but this one was cast without the center lug on the crankcase. It's an A12 & I guess that we could speculate that it is a very early example, but I don't know for sure.















This is my A13 block & the third mounting lug with strengthening ribs is clearly seen. This one is now sitting in a recycling tub filled with diluted molasses.

H10 A12 B110 etc.
H72 A14 B210 etc. rear wheel drive
M72 A14 N10 Front wheel drive
some of the mounting points for front drive are different necessitating a different casting, and casting number

Thanks rgrinder. I was just curious if they meant anything.