What are the benefits of negative camber on track?

Negative camber makes the affected tire vertical in the corners, and slanted on the straights. Zero camber makes the affected tire vertical on the straights, and slanted in the corners.

Negative camber in track driving accomplishes primarily two things:

  1. It makes the car faster in the corners, because the size of the contact patch in the corners gets larger.
  2. It evens out tire wear by reducing wear on the outside shoulders in the corners.

Read more at the track alignment page.