Here is my direct experience after running M/T 29.5 x 10.5 -15' for 10 plus years as that is what was on the car when bought back in '99 so I always stayed with that tire, in 2009 on a Wednesday night track I went out with the usual M/T drag bias tires on the car and ran a usual 10.73 @ 126. Then went back to the trailer and bolted on a set of Hoosier 30 x 9 -15's C06 radials set the air at 18psi (no tube) that a friend had taken off a car he just bought and didn't want and ran 10.51 @ 129 45 minutes later. Car is a '68 road runner with cal traks, stock leafs and a 4.10 gear. In 2013 I sold the car and just bought it back 2 months ago, Car now has split mono leafs, double adjustable shocks on back and single adjustable shocks on the front so looking forward to getting it out again soon as that has helped get it in the teens I am told.