400-440

[Moparbob]

Are the 400 blocks and the 440 blocks the same size shape ect?

[Nacho-RT74]

diff height, due the longer stroke

[Challenger340]

As stated
The 440 Blocks have a higher Deck Height to accomodate the longer stroke, therefore Intake Manifolds are also wider and not interchangeable.
440's also have a larger main Brg. Diameter.

[Nacho-RT74]

and dist shaft diff longer on 440s

didn't stated anything else because question was strictly about the block although forgot talk about the mains LOL.