With a 400 in a C body, you will need all the low end tq you can get.
People forget that before you can get to 4000 rpm, you have to get to 2000 rpm first.....
And to get to 2000 you need to get to 1000. So what? Who in their right mind is stabbing the throttle under full load at 2000? No one should be.
Guys get all wound up about torque at WOT, but what do you lose 30 foot pounds at 3500 at WOT (as an example) compared to 3500 at a quarter throttle? It might be 7 or 8 foot pounds. Maybe.