A Platform for Performance:  Corvette C5-R Chassis

A Platform for Performance:  Corvette C5-R Chassis

Source:  GM Media

The distance from Main Street to the Mulsanne Straight is not measured in miles, but rather in attitude. Some engineers might pale at the thought of hurtling down a two-lane country road at 190 mph. For the Corvette Racing team, however, 24 hours at Le Mans is simply a long day (and night) at the office.

The 2003 Corvette C5-R chassis retains its perimeter frame design using hydroformed rails from the production vehicle. Another great example of racing technology that emulates production practice.

The competition is fierce and the demands are rigorous, but Corvette Racing has the advantage of a solid foundation for its endurance racing program - the production C5 Corvette chassis. The Corvette C5-R race car doesn't just share its aerodynamic shape with the fifth-generation Corvette street car. It also shares many of its chassis components - as well as the engineering and technology that are required to craft a world-class automobile.

"The Corvette has always been at the cutting edge of sports car performance," said Dave Hill, Performance Cars vehicle line executive and Corvette chief engineer. "The general architecture of the road car contributes to its success at the track. The low center of gravity and long wheelbase that make the Corvette a very stable vehicle at speed also contribute to making it a comfortable street car."

While the Corvette C5-R is a purpose-built racing machine, it employs many production components. The stock hydroformed frame rails are the base for the roll cage; the power steering pump and steering rack are standard C5 parts. The race car's body design is based on the production car CAD (computer-aided design) data. The windshield, taillights, and marker lamps are the same parts installed on the Corvette assembly line in Bowling Green, Ky.

The production Corvette coupe is one of most aerodynamic shapes on the road today with a 0.29 coefficient of drag (Cd). More importantly, this efficient design produces very little lift, even at high speeds. The production silhouette gave GM Racing aerodynamicists an exceptional body design that is augmented with wings and aerodynamic devices to provide additional downforce. In racing trim, the C5-R produces enough downforce at speed that it could theoretically drive upside down on the ceiling of a tunnel.

GM engineer Ken Brown took a sabbatical from his work with the Corvette development team to contribute to the Corvette Racing project. His familiarity with the advanced technology and technical resources of the world's largest automobile manufacturer directly benefited the C5-R program.

"We used many common processes in developing the C5-R," Brown said. "Our analysis tools, like finite elements and our other CAD/CAM data tools, were used extensively. We also incorporated suppliers for the production Corvette in the racing program."

The 2003 Corvette C5-R chassis retains its perimeter frame design using hydroformed rails from the production vehicle. The Corvette race cars utilize six-speed Hewland transaxles that weigh less than the separate transmission and rear-end assemblies used previously and improve weight distribution by moving the gearbox rearward. This is another example of racing technology that emulates production practice: The street Corvette's rear-mounted six-speed manual transmission helps it achieve near-perfect 50/50 weight distribution.

The championship-winning Corvette C5-R race car does indeed have an unfair advantage - the pedigree that comes from decades of exhilarating performance and innovative engineering. It's a tradition that is the heart and soul of the production C5 Corvette, and a heritage that inspires the C5-R competition Corvette.