A Look Behind the Scenes at the Evolution from Also-Ran to Winner.
When the factory-sponsored C5-R Corvette race cars debuted in the '99 Rolex 24 Hours at Daytona, optimism was so thick you could cut it with a knife. But, long before the end of that grueling 24-hour endurance race, any hope for success had long since vanished. Transmission problems, differential failure and, ultimately, an engine failure dashed all hopes of earning a coveted class win.
With hindsight it's easy to identify where, when, and why things went wrong. But at that time the optimism seemed entirely reasonable. After all, in two years of development and testing preceding the Daytona contest, the C5-R racing "mule" proved to be extremely fast. In fact, at certain tracks it exceeded the existing GTS class record during testing, even at Road Atlanta in the rain! "Don't get too excited about that," those in the know told the rest of us. For one thing, a rules revision would allow competitors to use a wider rear tire beginning in 1999, and the existing track records were set by Vipers running on the narrower tires. There was no telling what the Vipers would do on the new tires.
"Also," those in the know again cautioned, "never underestimate what your opponent is really capable of." How right they were! The factory Corvette team eventually worked out their mechanical bugaboos so that by the end of the '99 season the C5-Rs were becoming extremely reliable. But reliable or not, they still couldn't catch up to the ferocious, factory-sponsored Vipers. The Corvettes never seemed too far off the mark, recording a second place finish at Sears Point, a fourth place at Road Atlanta, another second place at Laguna Seca, and a third place at Las Vegas. No matter how hard they tried, though, the Oreca team factory Vipers were one step ahead. Were the Vipers sandbagging, running only hard enough to stay out in front without showing their entire hand? Or were the Corvettes forcing them to go that much faster? Probably a little bit of both.
"The Vipers had no real competition until the Corvettes came along," points out one GM engineer, "so they weren't really trying. We made them try, and that ultimately showed us just how good they were and just how much work we had to do."
The C5-Rs went into the '00 season with a valuable year of actual racing experience under their belt and a couple of major improvements incorporated into the cars. One of the more important of those improvements, a larger engine, actually came on board in October 1999 at the Laguna Seca race.
Chevrolet engineers realized early on that American Le Mans Series rules, intended to level the playing field among cars with different size engines, were skewed in favor of larger displacement engines. Though the Dodge Vipers had to use a smaller intake manifold air restrictor on their 8-liter V-10 engines compared with the restrictors Corvettes used on their 6-liter V-8, the Vipers had a clear power advantage. To overcome this, GM Racing engine point man John Rice and Kevin Pranger, engine development specialist from Katech (the company that actually builds the C5-R's engines), bored and stroked the LS1 to 7-liters. At this displacement the Corvette engines are just about the equal of the Viper's. Besides the larger engine, another important change that helped the Corvette racers in 2000 was what GM calls the second generation C5-R chassis. Though work actually began on the new chassis in 1999, the first one was not ready to race until the Mosport ALMS race in August 2000. The new car won high praise from team drivers Ron Fellows and Andy Pilgrim, who led most of the Mosport race only to fall into second place at the end when the rain soaked tracked dried off and their Goodyear rain tires forced the Corvette to slow down. In a heart-wrenching finish the Corvette crossed the finish line just 0.353 second behind Oreca's class winning Viper.