Originally Posted by skierman64
Understeer is caused by too much traction at the rear axle caused by overly wide tires thus the front end is the first to break away. Many E46 owners who track their cars when with the same size tire front and back to get a more balance turn with less oversteer. Plus it allows for swapping tires front to back, reducing tire cost for track days. Only on very slow corners at the track does rear traction become a concern due to too narrow rear tires, in my experience.
While thats true, I suspect most E46 M3 owners that are running 9.5" all around today could be faster with a 9.5" front and 11" rear setup.
A stable car (understeer) is easier to drive at the limit. Also adding grip never slows down the car. All else being equal.