400 stroker or 440

I'm glad someone posted a link to the "451 manifesto".

The advantages are:

slightly stronger
slightly lighter
slightly smaller
slightly more CID

all are small, but add up, and the big one-

more efficient.

That's why the Ford 302/5.0 (old, not new) was able to hang with and beat 350/5.7 GMs.

Contrary to popular belief, it's NOT all about displacement, although the 451 gives you that as well.

Don't get me wrong, I love 440s, but the 451 is just mathematically a better design.