Just a day after a new federal energy bill calling for dramatic increases in fuel efficiency works its way out of Congress and on to the White House, General Motors Corp. unveils the ’09 Chevrolet Corvette ZR1, the fastest, most powerful and likely most expensive vehicle the auto maker has ever produced.

Rumored to exist as the “Blue Devil” ever since the current sixth-generation Corvette launched in 2004, the new ZR1 builds on the legacy of the previous ‘90 Corvette ZR1, with a mission to deliver the ultimate performance experience without sacrificing driveablity.

“The ZR1 is a car anyone can drive confidently and comfortably,” says Tom Wallace, vehicle line executive-GM performance cars. “From the very beginning, refinement, balance and compliance were targets that were as important as the car’s maximum performance.”

The new model, which GM will introduce formally next month at the North American International Auto show in Detroit, is built upon the aluminum spaceframe of the already-stout $71,000, 505-hp Corvette Z06.

To reduce weight and increase aerodynamic stability at high speeds, several of the Z06’s composite body panels have been redesigned in carbon fiber, including the painted hood and wider front fenders, as well as the exposed carbon-weave roof panel, roof bow, chin spoiler and rocker panels.

Also featured is a more aggressive full-width rear spoiler, polycarbonate engine window in the hood bulge and a special ultraviolet light-resistant clear coat to prevent excessive wear and yellowing of exposed carbon fiber elements.

New 19-in. front and 20-in. rear aluminum wheels, available in silver or chrome and wrapped in ZR1-specific Michelin Pilot Sport 2 tires, add to the car’s curb appeal.

Although based on the Z06, the ZR1 will be powered by the all-new 6.2L supercharged and intercooled LS9 OHV V-8, rather than the 7.0L LS7 small block. Official figures will be released in spring, closer to the car’s production launch in summer, but GM promises at least 620 hp and 600 lb.-ft. (814 Nm) of torque.

Mated to a revised and race-hardened version of the Z06’s 6-speed manual transaxle, the 3,350-lb. (1,519-kg) ZR1 easily should best its lesser stable-mate’s 3.7-second 0-60 mph (97 km/h) time and 198-mph (319-km/h) top speed, says Tom Stephens, group vice president-GM Powertrain and Quality.

A unique, sport-tuned version of the Z06’s suspension puts the power to the ground. However, due to the standard fitment of Magnetic Selective Ride Control, the ZR1-specific tuning can be configured for comfort on the street, yet retain firmer, more responsive settings for aggressive driving and track use.

Halting excessive forward motion is handled by massive carbon-ceramic disc brakes, which come standard and measure 15.5 ins. (39 cm) across in the front and 15 ins. (38 cm) in the rear. Clamped by 6- and 4-piston front and rear calipers, respectively, the ZR1’s cross-drilled discs have twice the swept friction area as those on the Z06 and likely will last the life of the car, the auto maker says.

In addition, the lightweight construction of the carbon brakes aids the performance of the ZR1 by reducing weight at each corner by approximately 11 lbs. (5 kg) vs. conventional cast-iron rotors.

Inside, Corvette aficionados will feel right at home, as little has changed from the lesser models. “ZR1” logos adorn the sill plates, headrests and new gauge cluster, which also sports a larger 220-mph (370 km/h) speedometer and a boost gauge (also integrated into the Head-Up Display).

Similar to the Z06, the base ZR1 interior will have minimal sound insulation and luxury content. A “luxury” package will be the sole option for the car and will add unique power seats, leather-wrapped interior trim, navigation and Bluetooth connectivity.

Available colors will include Black, Velocity Yellow Tintcoat, Victory Red, Atomic Orange Metallic, Jetstream Blue Metallic Tintcoat, Blade Silver Metallic and Cyber Gray Metallic.

“It might look like a Z06 with aero enhancements, but it’s way beyond that,” says Corvette Chief Engineer Tadge Juechter. “This is the pinnacle of technological development – a high-water mark not just for GM but also for sports cars, in general.”

GM has yet to say how many of the limited edition ZR1s will roll off the line in Bowling Green, KY, or, what the entry price will be. But educated guesses point to only a few, and a lot, with a starting point that likely will match the Cadillac XLR-V’s $100,000 sticker a definite possibility.

“What sets it (ZR1) aside (from competitors) is its docility – the ease of driving,” says GM Vice Chairman Bob Lutz.

“It is so easy to drive around town, but once you step into it, Clark Kent turns into Superman – a never-ending rush of power that is way, way beyond the Z06.”

msutton@wardsauto.com