Help with 440 casting numbers

[Hadahemi]

I'm confused...I have heard of 440-1 and 440-3 blocks, turns out mine says 440-8. Can anyone shed some light on what differences these blocks have? Any info or links would be much appreciated.

 

[Mrmopartech]

The -8 or any of the -numbers is for how many times the casting core has been modified or retooled back to spec.mrmopartech

 

[Hadahemi]

That makes good sense to me, but then what about the RV engines that were different from all the others, how are they identified?