Aero Is King
By the time designers were informed of the Aerotech project, Louckes and company had established most of the program’s specifications. The car would consist of a slick, GM-designed carbon-fiber body riding on a modified March 84C CART chassis, similar to that used to win the Indianapolis 500 that year. Power would come from a Quad 4, of course, albeit a turbocharged, 2.0-liter variant capable of spitting out over 900 horsepower.
That mission floored Welburn, then the assistant chief designer in the Oldsmobile studio. Although he was primarily tasked with crafting the exterior for the 1988 Cutlass Supreme, Welburn was infatuated with endurance racecars -- cars that bore a remarkable resemblance to what Louckes was looking for.
“I loved cars that ran at Le Mans,” Welburn told Automobile, “like the Porsche 917s, and especially the Chaparrals. I often found myself sketching such vehicles as a side while working on the W [body] cars, and the Aerotech project was my dream assignment.”
Welburn found himself sketching a number of elongated, slippery race car shapes in early 1985, but a single drawing was apparently all it took. His first Aerotech concept rendering quickly caught the eye of Buick-Oldsmobile-Cadillac executive design director Len Casillo, who quickly ran it up the flagpole to design director Chuck Jordan and design vice president Irv Rybicki. Both men quickly gave their approval.
“I kept telling them I had other ideas; other sketches,” Welburn chuckles. “But they were sold on the first sketch.”
After logging long hours working on the Cutlass Supreme and other production vehicles, Welburn, along with sculptor Kirk Jones, would labor on the clay models in secret at night. Although the first draft appeased Welburn’s bosses, it would need to be vetted in the wind tunnel -- after all, cutting aerodynamic drag plays a large part in improving a vehicle’s top speed.
“His initial design was very good,” recalls Max Schenkel, an aerodynamicist at GM who also served as a staff engineer on the Aerotech project. “It had a lot of potential for low drag, but we needed to refine a few aspects.”
Wind tunnel testing, performed both at GM’s Technical Center in Warren, Michigan, and abroad by March’s staff, pushed the designer to round the Aerotech’s nose and refine the canopy shape, along with moving the cooling system intakes from the sides to the top of the fenders. Welburn’s original concept called for faired-in wheel wells, but Goodyear engineers expressed concern that such a design would retain heat and reduce tire life.
Arguably, Aerotech’s biggest aerodynamic trick lurks underneath its sinewy form. The car is fitted with adjustable underbody panels from bumper to bumper, which incorporate deep air channels that run the entire length of the car. This system not only created a tremendous amount of downforce, but also allowed crews to precisely dial it in for different courses.
Welburn’s original design called for a long tail, inspired by the famed Porsche 917LH, but this conflicted with Louckes’ plan for legendary Indy 500 driver A.J. Foyt to drive Aerotech to a closed course record at Indianapolis Motor Speedway. A long tail may be the ultimate low-drag shape, but a short tail -- coupled with a secondary pedestal spoiler -- provided the proper downforce for Indy’s corners.