Jim Hall is part of a very small group of racing engineers who brought important and long-lasting evolutions to the world of motor sport. The son of a family of American oil producers, Jim Hall started out as a driver before becoming a manufacturer, which gave him plenty of opportunities to exploit a close relationship with the technical management of GM.
1963. The Chaparral 2A, in its evolution, experiments with innovative front splitters
When he decided to abandon his driving ambitions, for which he had also begun to build his own sports cars called Chaparral, he devoted himself to the continuous and fruitful application of technical and aerodynamic innovations that brought the entire motoring industry to a turning point. Taking advantage of GM’s wind tunnel, in 1963 he had already introduced intelligent modifications to his Chaparral 2A with very visible aerodynamic appendages to increase front-end grip around the circuit. This experience was developed further in 1966 with the 2E which featured a large rear wing attached directly to the rear suspension uprights, loading the tyres for extra adhesion while cornering.
1966. The Chaparral 2E Can-Am ushers in the era of spoilers. No-one imagined their future importance
What seemed like an extravagance transformed into a veritable revolution that led to the current use of aerodynamics to increase car performance far beyond racing. Jim Hall, who developed his activities both in Europe, in the Sport Prototypes Championship, and in America, in the Can-Am Championship (from Canada to America) in those years, made full use of GM’s research into production cars, transferring data and insights to the world of competition.
1967. The Chaparral 2F that competed in the Sport Prototypes World Championship, losing it at the final race
These exploits reached new heights when, in 1970, he entered the Chaparral 2J in the Can-Am races, cars that sealed the air beneath the car using what we now call the miniskirt effect, extracting it with two fans housed at the rear to create truly incredible levels of downforce.
The wing of the 2F worked like the current DRS in F1: the driver could open or close it via a pedal mounted in the cockpit. The automatic gearbox left the foot free for this operation
As incredible as it seems – and it is well documented for all you non-believers – this further step forward in the history of aerodynamics was inspired by the experiments that GM was carrying out on its Corvair production model, which had been criticized by the media for poor road holding. To correct this inconvenience, GM technicians had noticed that by sealing the air beneath the car by lowering the sides, it became more stable. An impractical solution for road use, but one that gave Jim Hall the idea of bringing the ground effect principles to racing with the 2J.
1970. With the 2J, side “skirts” made their first appearance, creating ground effect for the car. Another great revolution by Jim Hall
Curiously, these great innovations soon became a part of the heritage of Formula 1, with Ferrari being the first to mount a wing on its 312 F1, and Lotus dominating with the 79 which exploited ground effect to the max. The exploits of Chaparral have largely been forgotten, but if today motoring has come so far, much of the merit is due to this small but very courageous American manufacturer.
To maximize the amount of downforce on the rear of the car, there was no limits to his imagination: the 2J had two fans to extract air, which made it totally unbeatable
CLASSIC CAR MATCHER