COBALT READY FOR RECORD ASSAULT ON BONNEVILLE SALT FLATS

WENDOVER, Utah - One year ago, GM Performance Division's race-prepared Cobalt SS blitzed the Bonneville Salt Flats at 243 mph. That scorching run was just a dress rehearsal for this year's record assault.

This time it's for real. The Cobalt race car was ineligible to set an official mark in 2004 because Chevy's new front-wheel drive sport compact wasn't yet available in Chevrolet dealerships. Now that the assembly line is rolling and production Cobalts are turning heads on streets and highways, GM Performance Division is gunning for the record in the G/Blown Fuel Altered class.

GM Performance Division engineers are aiming to shatter their own record. In October 2003, GM engineer Jim Minneker set the standard in the G/Blown Fuel Altered class at 212.684 mph driving a Saturn Ion Red Line coupe. Minneker and his Saturn bettered the previous record by more than 30 mph. Considering that the Cobalt has already topped 243 mph in last year's warm-up, the class record is again in jeopardy.

The Cobalt SS Bonneville race car - a modified version of the 2005 Chevrolet Cobalt SS Supercharged sport compact coupe - has the advantage of six months' additional development. It's not the same machine that rolled onto the salt last year; it's been honed to an even sharper edge by GM Performance Division.

"The fact that the Cobalt achieved 243 mph last year exceeded our expectations," said Mark Dickens, program manager for GM Performance Division's Bonneville project. "Since then we've made changes to the car that should increase its speed."

Dickens will experience those changes firsthand when he succeeds Minneker as driver of the Cobalt SS race car. An accomplished SCCA road racer in the open-wheel Formula 2000 and Formula Continental class, Dickens piloted GM Performance Division's Ecotec Lakester to a 179.381 mph record in October 2004.

"We focused our effort on improving the front-wheel drive Cobalt's traction on the salt," he said. "Last year we didn't run out of horsepower, we ran out of grip. We've added weight to the front end, increased the size of the turbocharger to enable the Ecotec engine to accelerate harder as it comes into boost, and we've spent time in the wind tunnel to improve the body's coefficient of drag.

"We'll start out conservatively to make sure we set the record," Dickens revealed, "and then we'll turn up the wick to see what the car can really do."

With more than 1,000 horsepower on tap, the car's capabilities are impressive.

Like the production Cobalt SS Supercharged, the Bonneville race car relies on a 2.0-liter Ecotec engine with forced induction. The Bonneville racer's turbocharged 2.0-liter, four-cylinder Ecotec was originally developed by GM Racing for Sport Compact drag racing, where it has won NHRA championships in the PRO FWD and Hot Rod classes. The race-prepared Ecotec engine and Hydra-Matic automatic transmission have proven reliable under the vastly different demands and duty cycles of quarter-mile sprints and high-speed record runs that subject components to punishing loads and withering heat.

"The Saturn Ion Red Line and the Cobalt SS Supercharged are both based on the same GM small-car platform," explained GM Performance Division Executive Director Mark Reuss. "The Saturn chassis that we raced in 2003 was very close to stock specifications, and what we learned was applied directly to the production Cobalt SS Supercharged. When you run at extreme speeds, you learn very quickly where to spend your time on development. The Cobalt SS Bonneville race car is designed to run even faster, so we built a more race-oriented chassis to maximize safety."

The production Cobalt SS Supercharged has strong performance credentials in factory trim. Powered by a supercharged and intercooled 205-horsepower, 2.0-liter Ecotec DOHC four-cylinder engine and equipped with a tenacious suspension developed on Germany's famed Nürburgring race track, the production Cobalt SS Supercharged brings more heat to the already red-hot sport compact segment.

"Our goal is to build enthusiasm around a car and an engine that we are very excited about," said Reuss. "This year we're racing at Bonneville under the Chevrolet banner with a sport compact that's aimed at young performance enthusiasts and an Ecotec motor that's quickly becoming the small-block V-8 of four-cylinder engines."

The Cobalt SS Bonneville race car was built to the standards prescribed by the Southern California Timing Association (SCTA), the organization that sanctions the Bonneville Speed Week. A roll cage constructed of 1.750-inch diameter-by-0120-inch wall steel tubing surrounds the driver. A 22-gallon tank filled with ice and water replaces the passenger seat; an electric pump circulates the cold liquid through an air-to-water intercooler that chills the intake charge. A 33-gallon water tank occupies the space usually reserved for the back seat; this reservoir supplies coolant for the engine and eliminates the need for a conventional radiator. A trunk-mounted 16-gallon fuel cell carries the methanol fuel consumed by the engine and helps to balance the weight distribution.

In keeping with the grassroots tradition of Bonneville, the Cobalt SS Bonneville is a simple, straightforward race car.

"The Cobalt SS Bonneville race car is really very close to a production car," said Pete Chapouris, president of So-Cal Speed Shop, GM Performance Division's technical partner in the Cobalt program. "The floorpan and firewall are basically stock, and none of the exterior body panels have been modified. This is a car built by hot rodders following the specs in the rulebook, and there aren't any tricks or secrets. It's just a straightforward approach to Bonneville racing that a guy could build in his garage."

There are some high-tech touches, however. The four-speed Hydra-Matic automatic transmission can be shifted electronically by pushing buttons on the steering wheel spokes. The Cobalt's 10-inch rear wing and spill plates were developed in the wind tunnel to enhance stability, along with NASCAR-style roof flaps that are designed to keep the car on the ground in the event of a high-speed spin.

"Our goal was to maintain as much of the production Cobalt's identity as possible in the race car, with only minor aerodynamic enhancements," said Kip Wasenko, director of design for GM Performance Division. "The SS heritage is an important part of what makes Chevrolet a great American brand. Now we're getting outrageous power and performance out of a new breed of small-displacement, high-tech engines."

With an aerodynamic design, a powerful engine and a seasoned crew of Bonneville fanatics, the sequel to GM Performance Division's record-setting performance promises to be as thrilling as the original.

Cobalt SS Bonneville Race Car Specifications