No, actually it is to do with the pinion angle.
You could go to the lengths of repositioning the arm mounts on the diff to bring the pinion angle back but you will find that the traction will be lost again.

Don't ask me exactly why it is so but thats what happens.

On a side note, sedans in speedway typically use 2 - 3 degrees nose down on pinion.

Another thing to bear in mind with changing the pinion angle is that when you increase positive acceleration traction you are decreasing negative acceleration traction by the same amount. i.e. the more traction you gain on acceleration the less engine braking traction you will have.

Monkeywrench, what you described is usually referred to as a torque arm and reduces the amount of spring wrap on high hp leaf sprung cars.