SI Vault
Brock Yates
July 20, 1970
They all laughed when Jim Hall unloaded his vacuum-cleaner racer. But the monster may be the Can-Am design of the future
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July 20, 1970

Box? Bar Of Soap? No, It's A Car

They all laughed when Jim Hall unloaded his vacuum-cleaner racer. But the monster may be the Can-Am design of the future

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When more bizarre racing cars are built Jim Hall probably will build them. Operating from his Midland, Texas headquarters, this brilliant, millionaire designer-driver has maintained his position in the vanguard of far-out car creators ever since he built his first sports-racing Chaparral nearly a decade ago. He was the first man to effectively stuff a large domestic power plant into a lightweight rear-engine chassis; the first to build an all-plastic racing car; the first to perfect an automatic transmission for competition; and the first to employ a wing, or airfoil, for road-racing application. What's more, his innovations have worked.

This past weekend, away off in western New York, Hall took another quantum design leap forward when he arrived for the Watkins Glen Canadian-American Challenge Cup with a machine that left the racing gentry shaking slide rules in disbelief. Tradition demands that racing cars be sleek and willowy, hugging the ground like crouched felines. Hall's Chaparral 2J looks as if somebody had carved it out of a giant block of soap. It represents all of the glamour and beauty to be found in the average mobile home. But Hall is an engineer, not a stylist, and the 2J's ugliness is an embodiment of that old adage about form following function. After a mere 19 laps of practice in the car, world driving champion Jackie Stewart motored around the 2.3-mile Glen circuit at 130.19 mph, within one second of the absolute lap record, and climbed out to proclaim, in his thickest Scottish brogue, that the 2J "has more adhesion to the road than any car I've ever driven."

Despite the Chaparral's potential, it did not win its racing debut. But it did produce one indication that this could be the start of something big: it ran the fastest lap in the race, a fine 125.8 mph turn. Otherwise, the Can-Am simply produced another easy victory for the McLaren team—its 16th in succession. Stewart had started third on the grid (he had qualified the white monster at 103.69 mph), behind Denis Hulme and Dan Gurney. And he motored around in that same position for 14 laps before vacuum problems forced him back to the pits.

Stewart climbed out of the cavernous cockpit to announce that the revolutionary suction system had not been working properly from the start and to claim that he could have led the race easily if it had been operating at full efficiency. After 29 minutes of fiddling by the Chaparral mechanics he tried again for eight laps, then quit for good.

Stewart was boarding an airplane in nearby Elmira, bound for New York, when Hulme's pumpkin-colored McLaren took the checkered flag 28.5 seconds ahead of Jo Siffert's Porsche 917. There was little jubilation among the Hall team, in spite of Stewart's one quick burst, but the result seemed clear: with more development and improved reliability, the 2J may become the fastest car in Can-Am history.

The key to the 2J's auspicious debut lies in a pair of fans mounted in the back of the car. These devices turn the machine into a giant vacuum cleaner that literally sucks away at the road surface, keeping the wheels glued to the ground. The vacuum is held by a set of wraparound skirts made of a sturdy, space-age plastic. As racing-car speeds have rocketed in recent years, a major problem of tire adhesion has arisen: at 200 mph, rakish, pointy-nosed automobiles begin to act like airplanes. They yearn for flight. To keep them stuck to the surface of the earth, spoilers have been mounted to break up the airflow, tires as wide as steamrollers have been added and, behind Hall's design thrust, reversed airfoils, or wings, have been bolted on above the bodies to exert a negative down force on the wheels. But all these components interrupt the airflow, cutting speed, and for a number of years racing-car designers have been seeking a setup that would keep the car firmly in contact with the road while not causing a reduction in the ability to go fast.

The 2J may be the answer. With its two fans (driven by a two-cylinder snowmobile engine) whirring away, the Chaparral scuttled around the Glen circuit with an estimated 1,000 extra pounds of down force on the wheels. To obtain an equivalent amount of adhesive pressure on the track, Hall would have to have added half a ton of weight to the car. But sheer bulk obviously impedes acceleration, cornering and braking, and is therefore unacceptable. The old auto salesman's adage that a "heavy car holds the road" is true in a sense, but not when measured in sheer tonnage. Hall therefore added weight through an ingenious system of aerodynamic suction referred to in engineering terms as "ground effect"—or the fact that suction is used as a substitute for all that heavy superstructure.

"The entire concept of the 2J started in casual conversation about a year and a half ago," said Hall, 34, as he leaned his lank, Texas cowboy frame against a toolbox in the Watkins Glen garage area. "We were discussing the kinds of racing-car designs that could reduce lap speeds in a revolutionary sense. You know, evolutionary development of an existing car can bring about a two or three percent reduction a year, but we were talking about a startling reduction, like 10 or 20 percent, and in that context the ground-effect thing made sense."

Hall and his tightly organized, abundantly talented crew at Chaparral Cars, Inc. followed up the conversation with a prototype machine that was running last fall on their own secret desert test track, known as Rattlesnake Raceway. The initial tests were highly encouraging, but then a waterline broke and Hall—who was in the cockpit during a trial run—was burned and the program interrupted. It was his second serious accident within a year, the first being a near-fatal flip in Las Vegas during the 1968 Can-Am season, and the development of the Vacuum Cleaner, as the 2J was labeled, was slowed down until Hall's burns healed. "I decided I was going ahead with the thing come hell or high water. We redesigned it a couple of times, and now we know the capability is there for that startling reduction in lap time I was talking about," he says.

To achieve that capability, Hall sought the services of the man correctly acknowledged to be the best road-racing driver in the world. The man is Jackie Stewart, whose poise and professionalism on and off the racetrack are becoming legendary. A thoroughly plugged-in guy in the modern idiom, Stewart was an obvious choice for a spearhead design like the Chaparral.

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