2008 Pontiac G6 GXP.R

(from General Motors Press Release)  Pontiac unveiled the GXP.R racecar, which will compete in the GT class of the 2007 Grand American Rolex Sports Car Series presented by Crown Royal Special Reserve. The GXP.R hits the track running later this month at the famed Rolex 24 Hours of Daytona race in Florida.

With the bodywork inspired by the Pontiac G6 GXP Street edition coupe, the GXP.R is the next step in the evolution of a successful racing program that began with the purpose-built GTO.R. The GTO.R was retired after winning the 2006 GT championship; the new GXP.R is built on the same winning foundation as the GTO.R.

“The GXP.R begins the next chapter in a very successful racing campaign that has put Pontiac over Porsche and BMW in the highly competitive GT class,” said John Larson, Pontiac general manager. “The GXP.R promises to pick up the GTO.R’s momentum and carry it into another winning season.”

Built to the specifications of the Grand American GT class, the GXP.R features a rear-drive layout and a racing version of the LS2 V-8 engine that produces approximately 450 horsepower (335 kW). It is based on the same Gen IV V-8 engine design as found in the production Grand Prix GXP. The production G6 GXP is powered by a sophisticated, DOHC 3.6L V-6 with variable valve timing that produces approximately 252 horsepower (188 kW).

The GXP.R’s bodywork retains the silhouette of a production G6 GXP, but lightweight, carbon-fiber replica panels are used throughout to reduce overall mass. The stock window glass also is replaced with lighter, shatter-resistant polycarbonate pieces. The body panels are attached to a custom tube-frame chassis, with the front and rear fenders flared to cover the wide, 18-inch wheels and class-spec Hoosier racing tires. Also, a huge rear wing that provides stabilizing downforce is tied into the chassis. It’s not a production-model wing, but the G6 GXP street car has its own distinctive rear spoiler.

Production-based racing

The Grand American GT class is comprised of production-based coupes and sedans that are modified for racing. Many of the engine components must be the same as those found on production models. The tube-frame chassis and ground-hugging bodywork are used to ensure high-speed traction and stability, while a purposeful interior deletes amenities such as air conditioning and an MP3-capable radio for a crisscross of safety roll cage tubing, a single racing seat, racing instruments and other race-only accoutrements.

Grand American Racing’s racing series, which also includes the Daytona Prototype class, was founded in 1999 with the goal of reinvigorating American road racing. Pontiac models were campaigned in the GT class from its inception, and the GTO.R program was launched in 2005. In their first full season of competition, two GTO.R teams dominated the 2006 season. With eight wins, including a podium sweep at Phoenix , Pontiac clinched its first GT Manufacturers championship, and the No. 65 TRG/F1 Air GTO.R of Andy Lally and Marc Bunting took the GT Drivers and Team championship. The No. 64 TRG GTO.R of Paul Edward and Kelly Collins finished third in points. The remainder of the class’s top 10 finishers included five Porsche GT3 Cups, a BMW M3 and a Chevy Corvette. During the 2005 and 2006 seasons, the GTO.R amassed an impressive 19 consecutive podium finishes – a class record.