How GM fixed tire slippage from the inside out
Andy Bolig - March 28, 2014 12:35 PM
Engineers resorted to bead blasting the beads of the rims to ensure enough friction to keep the tires from spinning on the rims.
At the end of the lap, they recorded where the chalk line ended up and noticed the tire had rotated at least a full 360 degrees from where they started.
Keeping a tire firmly planted to the road is important on a performance car, keeping tires on the rims is even MORE important!
The only time that tire slippage becomes an issue is when you’re trying to put down some serious horsepower or slowing down from a recent endeavor. If the tires get a really good tooth on the road and the brakes are beyond those of mere mortals, there’s one other spot that could act as a fuse to prevent chunks of asphalt from going airborne – and GM found it on the new Camaro Z/28.
Engineers noticed that during extreme handling and performance maneuvers, the bead of the tire was losing its grip on the wheel’s mating surface. The Z/28 is a good-sized car, and still offers exceptional performance for its size. These attributes have surely contributed to over-reaching the bead’s locking ability, even on those low-profile tires.
They sought the root of the problem by marking one of the Pirelli P Zero™ Trofeo R tires at the beginning of a lap with a chalk line relative to the valve stem on the wheel. At the end of the lap, they recorded where the chalk line ended up and noticed the tire had rotated at least a full 360 degrees from where they started.
Check out this video of how GM engineers used both high-tech and simple know-how to identify, and rectify the situation.