I think ScottJ said it all.
It's about torque and the torque curve. If you can get your torque curve to get you about 85% of peak by 2600 rpm and stay within 15% of peak through 6000 rpm you will have a good steady hard pulling motor throughout the gears.
I am speaking of a Big Block of course. The little blocks are a bit different but it's still about making torque and having a good usable torque range to drive in.
Torque is a cars best friend.
