GM Performance Division :: Tech Story

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The GM Performance Division is sponsoring an exciting engineering adventure for four female college interns this year. This team of women are spearheading the building of a land speed Chevrolet Cobalt performance car in the hopes of attaining a record with a 2 liter, naturally aspirated, Ecotec four cylinder engine in the Competition Coupe (G/GCC) class at the Bonneville Salt Flats. The project team is having the car built by the west coast shop, California Street Rods, in Huntington Beach, California, and will be on the ‘Salt at the August Speedweeks event.

Background Info On Students:
GM Performance Division Student Team member Idalia Ovalle handled all the powertrain activities for this land speed effort. That included selecting the parts, overseeing the assembly and tuning and installation of the system into the vehicle. Ovalle will be graduating this year with honors from the University of Houston with a Mechanical Engineering degree. She enjoyed the demanding nature of this project and believes it has helped her understand the demands of being an Engineer.

GM Performance Division Student Team member Tessa Russell was responsible for the creation and integration of the important chassis, suspension, fuel system, aerodynamics and brake systems. She is a Mechanical Engineering student at the University of Missouri-Rolla. Russell has written research papers on space suits and designed the suspension on a student solar car project, so leading the key areas on this land speed effort was just another enjoyable challenge.

GM Performance Division Student Team member Sarah Jubenville is a Michigan native attending Purdue University as a Mechanical Engineering student. She was responsible for interior packaging, safety systems and driver communications on the project.

Jubenville was looking forward to driving the Cobalt, but a severe storm stopped land speed runs—postponing their run to at least October of this year.

GM Performance Division Student Team member Heather Chemistruck, an engineering student at Virginia Polytechnic Institute and State University, was responsible for the electrical system, powertrain cooling system and mass distribution calculations. Chemistruck had previous experience on a local race team and in a local repair shop, which served her well in this demanding buildup project.

Student team members Sarah Jubenville, Idalia Ovalle, Tessa Russell and Heather Chemistruck look ready to go for records with their Chevy Cobalt at the 2005 Bonneville Salt Flats Speedweeks event.

The 2005 GM Performance Division Student Team Chevy Cobalt looks fast as it receives some care in the pits before making it’s next run on the massive expanse of the Bonneville Salt Flats.

Over its fifty years of service, General Motors has a long and storied history of success with the small block Chevy V8 engine. To celebrate the Small Block V8’s 50th anniversary while honoring that legacy, the GM Performance Division has built a replica of the first stock car powered by a small block V8 to win in the top ranks of NASCAR.

The year was 1955 and a Smokey Yunick-tuned, Herb Thomas-driven ’55 Chevy had just won at the storied Darlington Raceway against many fast, well-funded teams. This amazing win was just the first in literally thousands of wins in stock car racecars powered this incredible V8 engine.

The first step of this project was to locate a clean ’55 to use as the basis for the project. In short order, a semi-restored ’55 Chevy Business Coupe was located in Wisconsin and brought back to GM’s Technical Center in Warren, Michigan to be turned into a repli-racer ’55. The Business Coupes were popular among the racers because they were devoid of many components from the factory—like backseats, body trim and other weight-increasing components.

GM Performance Division Project Manager Ray Wojdacki, head technician Mark Taylor and a host of other ‘helpers’ pushed hard to ‘race-store’ this ’55 back to the standards of that era, while adding a few modern safety and performance amenities.

These improvements were required as this car was built to drive—and hard! Since being completed, it has smoked its tires on the HOT ROD PowerTour, at multiple media events, at the Goodwood Festival of Speed (in England), and will be seen on the streets at this year’s Woodward Dream Cruise in Detroit.

The car looks and drives great and everyone involved has had a great time building and driving it. Hopefully, you have or will get a chance to see it in action—racing great Junior Johnson says it really sounds and looks like it just pulled off the track at Darlington back in ’55!

This ’55 Chevy Business Coupe’ represents the first small block-powered stock car to win a race in NASCAR’s elite division back in 1955. Built by the GM Performance Division to honor the legacy of the small block V8 engine, this vehicle was recently driven at the Goodwood Festival by GM Performance Division Executive Director, Mark Reuss and multi-championship winning stock car driver and owner, Junior Johnson.

The stock cars of those days were definitely bare bones ‘stock’. Most racers chose the ‘Business Coupe’ because it did not have a back seat and usually was a stripped down vehicle. That was perfect for the racers as they took everything off they could to reduce vehicle weight. A four-point rollbar and five point harnesses were added to this ride for safety measures, otherwise it’s just like Smokey and Herb built it 50 some years ago.

One of the latest additions to the GM Performance Division Garage is this Dynapack chassis dyno system that uses separate power absorbers for each wheel. One of the Cadillac CTSv racecars was the first vehicle to be tested on this chassis dyno. The advantage of the separate absorbers used in this system is that a (two- or four-wheel drive) vehicle can be tested under acceleration in a straight line, off of turns and other non-linear situations with impressive accuracy.

The Dynapack chassis dyno system is impressive in its compact size and versatility, but even more impressive is its ability to test a vehicle accelerating off a corner.

Each absorber uses these couplers to bolt the driveline to the absorber. Having the proper coupler bolt pattern for the six-lug CTS-V required a little work, but once accomplished, the system worked great.