My Nitto 315 drag radials lasted about 10,000 miles. I've only been to the track twice an thought they might last a little longer... I think they still had life in them but there was a 4 inch wide bald strip in the middle and I failed safety inspection... I dont drive the car particularly hard and keep the pressure around 25psi. SO my question is to all of you that get 15-20,000 miles out of your Nittos, What can I do to get them to last longer?