The G6 was used in the GT class of Rolex Sports Car Series as a replacement for the Pontiac GTO.R after the GTO went out of production.
The cars are referred to as GXP.Rs and built by GM's endorsed chassis constructor, Pratt & Miller.

It is powered by LS2 V8 engine that produces approximately 450 horsepower (340 kW).
Weight saving features include carbon fiber body panels, shatter-resistant polycarbonate windows.
The custom tube-frame chassis is not at all based on the road car's chassis and the 6-speed gearbox delivers power to the rear wheels.
The front and rear fenders flared to cover the wide, 18-inch wheels and class-spec Hoosier racing tires.
A rear wing reminiscent of sports option package on the race car is fitted at the back, underneath the proper racing rear wing.

The G6 GXP also races in the NHRA Powerade Drag Racing Series Pro Stock class for Warren Johnson Racing.
The G6 was used in the GT class of Rolex Sports Car Series as a replacement for the Pontiac GTO.R after the GTO went out of production. The cars are referred to as GXP.Rs and built by GM's endorsed chassis constructor, Pratt & Miller.
It is powered by LS2 V8 engine that produces approximately 450 horsepower (340 kW). Weight saving features include carbon fiber body panels, shatter-resistant polycarbonate windows. The custom tube-frame chassis is not at all based on the road car's chassis and the 6-speed gearbox delivers power to the rear wheels. The front and rear fenders flared to cover the wide, 18-inch wheels and class-spec Hoosier racing tires. A rear wing reminiscent of sports option package on the race car is fitted at the back, underneath the proper racing rear wing.
The G6 GXP also races in the NHRA Powerade Drag Racing Series Pro Stock class for Warren Johnson Racing.
Pontiac G6