When the first C6 ZO6 prototype was shown at the Detroit auto show in 2005, it was displayed beside the newly revised factory race Corvette, the C6.R. While GM officials took pains to highlight the mechanical similarities between the two cars, there was one key area in which the flagship street and competition Vettes continued to diverge: the brand of their tires. The racer was fitted with racing slicks from Michelin, while the production car wore Goodyear F1 EMT run-flats. But unbeknownst to most showgoers, Corvette Chief Engineer Tadge Juechter and company were developing the upcoming 2009 Chevrolet Corvette ZR1 supercar on all-new Michelin rubber.
The switch mirrored an earlier move on the part of Corvette Racing. While the C5-Rs used Goodyears from 1999 through the end of 2003, these tires were dropped after a crushing loss to the Michelin-shod Ferraris at the Corvette's 50th anniversary race at the '03 Le Mans. The team studied the race data and determined that the Michelins provided Ferrari with the winning edge. The 2004 season proved a huge success for the now-Michelin-equipped Vettes, including a class win at Le Mans. So perhaps it was only natural that the Corvette engineering team would look to the French tire maker when developing the ZR1.
When the ZR1 was unveiled in 2007, the big news-besides the massive brakes and 638hp horsepower engine-centered around the car's Zero Pressure (run-flat) Michelins. The new tire received rave reviews from the automotive press, prompting many Corvette owners to seek them out as replacement rubber for their own cars. But while Michelin had released an all-season Zero Pressure tire for the C5 in 2001, the company lacked a comparable offering for the C6.
That changed in 2008, when the Pilot Sport 2 Zero Pressure (PS2ZP) was introduced for both the fifth- and standard sixth-generation Vettes. But much to the surprise of Z06 owners, the PS2ZP still wasn't available in OE sizes for their car. The reason? During extensive testing, it was found that the existing PS2ZP wasn't much better than the Z06's factory rubber. As a result, Michelin decided to suspend the release of the tire until sufficient performance improvements could be effected.
The tire was revamped, and in August Team VETTE was invited to the Spring Mountain Motorsports Ranch to compare the new Z06-sized (275/35 ZR18 and 325/30 ZR19) PS2ZP tire with its OE counterpart. Spring Mountain is located in Pahrump, Nevada, in the southwest corner of Nye County. It's essentially the middle of nowhere-45 miles west of Las Vegas and 60 miles east of Death Valley-which makes it a perfect spot for a racetrack. In addition to its full, 3.1-mile length, the Spring Mountain course can be divided into 1.5-mile upper and 1-mile lower sections.