What do these numbers mean?

[sixt9x33rs]

I saw these numbers on the back of a small block with the bellhousing removed. They were above the crank:

678636 386371 H35
371386

The H35 is not a casting date. The casting date was in the normal location.

Thanks

[JohnZ]

Those are foundry identifiers for the various patterns and cores used to form the sand mold for the block; they're unrelated to the final assembled configuration of the engine.

[sixt9x33rs]

Thanks John.

Were you in Charlotte for the National Convention?

[JohnZ]

Thanks John.

Were you in Charlotte for the National Convention?

Yes, I was - great convention! My Michigan Chapter is hosting the National next July.