Life is short, go for the big cubes.

It's the bigger torque that will move the B-body better.

All things being equal, the 383 has to spin higher, move more air, to make the same HP.

A 383 with the 440 crank (like a 451, but smaller bore) only makes a 438 at .060 over.

If you want fuel efficiency and awesome high end throttle response...........stay 383.