Back to CanAm racing and as detailed in our introduction to this championship, CanAm was raw and all about power and speed but not only. Some of the cars and development that happened and raced during the period the championship existed prove to push the boundaries of engineering to the limit. Experimentations were of all sort and not just about power. Design, aerodynamics, vehicle dynamics, it was about all that as well. Jim Hall and his Chaparrals were part of it and to myself, the best of all. So let’s introduce one of his most crazy creation, the 1969 Chaparral 2H, a sleek and very interesting design and oh, white as well !
Nicknamed the “White Whale” by the other teams in period, the Chaparral 2H has nothing conventional apart from the four wheels and engine being at the back. In a way, being conventional doesn’t really work in motor sport, that’s about catching-up if thinking like this and Jim Hall was not a conventional man in anything that him and his team produced. He couldn’t be as he was first an engineer and second, a driver.
The 2H was a sleek and tiny design put together in order to maximise aerodynamic efficiency as well as grip. It sported some unconventional technical characteristics such as a narrow body and track as well as a low mounted driver-adjustable rear wing. Why ? Well, the ideas behind Jim Hall thinking were simple.
First, the car was narrower than the opposition designs being just 170cm (64′ inches) wide and that was about 10cm (4′ inches) narrower than that year’s McLaren as an example, regarding the track of the car, it was just about 139,7cm (55′ inches) at the front and 142,2cm (56′ inches) at the rear. That was a big difference in track, with the McLaren front track being of 144,7cm (57.6′ inches) and the rear one being of 142,2cm (56′ inches). So why all that ? A normal designer would have thought that the greater the track would be, the better the contact patch would be and therefore the grip and traction would be enhanced. But not for Jim Hall.
Tyres and wheels width were unlimited in CanAm but after heavy testing and racing with his previous models, it was thought that the cornering load was only being put on the outside of the tires and that being also due to the independent suspension geometry of the days which resulted in a nearly unloaded inside wheel. Therefore the whole suspension design was thought with old and new ideas in order to maximise the contact patch of both front and rear tires in all cornering situation and it resulted in a narrow track and body but also some pretty unusual suspension design.
What was so unusual for the suspension ? Well, the Chaparral 2H sported a common design for fifties and sixties rear suspension but only now used on road cars mainly, the rear suspension used a De-Dion type beam axle. The De-Dion design was used as Jim Hall thought that it would serve as what it was first designed for, ensure the best grip possible from the inside cornering wheel and therefore maximizing the exterior one as well. That had in situ an effect on the track even if at its largest the Firestone tires were of a maximum width of 50,8cm (20′ inches) but it was also thought that by reducing the track and body width, the frontal area would be reduced and therefore help the straight line speed. Hall in Hall a package ?! Well it can be said, better suspension design to maximise grip and cornering speed with an effect on straight line speed, Jim was well ahead in terms of thinking !
Early thinking and development proved that the car was a good thought and even if never seen like that other than at the Chaparral headquarters, it first sported a full width roof with and front windshield making it a closed “bullet” shaped design with very low nose and that’s the reason for the mandatory side windows also being the windows of the car.
Other unconventional features included the chassis which was made, unlike all other Chaparrals, of a fiberglass composite structure forming a sort of eggshell for the cockpit and front bodywork with the rear structure consisting of a rear subframe holding the engine and drivetrain – the famous Chaparral automatic gearbox – together as a sort of stressed member under a removable tail. The radiators were moved from the side of to the back of the car in order to reduce drag and actually as single one was used and sourced from a Corvette as Jim Hall also had close link with GM and particularly Chevrolet.
Because of the rear suspension design and cooling arrangement, the exhaust exited through the sides of the car. With the help from GM he also developed a very low cross-ram injection equipped intake manifold in order to keep it as low as possible and which sort of looked like the Corvette Grand Sport from few years earlier. Back to aerodynamics, the car was low and sported that rear mounted wing, an unusual arrangement again for the time as all previous cars had the high hub mounted one. This one would be driver-adjustable using the third pedal in the cockpit, it would be kept flat in straight line to reduce drag and angled by the driver to add downforce when cornering. Something he had already experimented with the World Sports Car 2H model of 1967.
Through development, all sort of arrangement were made to the De-Dion rear axle design in order to cope with the oscillation and axle-tramp generated such as the addition of a U-Joint system at the top of it in order to permit controlled flexing. Another system was added in order to cope with the moveable rear-mounted wing which was a hydraulic weight-jacking system helping maintain the pitch-angle of the car no matter what the aero load was. Again, a pioneering device and sort of active suspension idea..!
Unfortunately, the design didn’t prove to be that good on track… John Surtees, the driver of the car that year as Jim hall put an end to his driving duties described the handling of the car as awful. He was also the man who convinced Jim Hall to open the car and review the design and finally the one who got that massive wing fitted above the cockpit. Anyway, the straight line speed advantage didn’t really come together and that maybe being caused by those big rear tires being so close and having an effect on underbody airflow ? Who knows, there was also that massive wing now fitted.. The car wheelbase was also short so maybe that didn’t help as well with the power it had and the fast curves of the American circuits. All in all, it was a complete fail with the car only qualifying for five of the eleven rounds and finishing four of them during that 1969 season which also lead to Surtees leaving the team.
What remains of it today, well, it was radical for its time, maybe too much but we love it because where else could you have seen that in period ? Yeah, that was CanAm and Jim Hall particularly, but I’m not finished with this man and I’ll get back to him later anyway as he proved to have other fantastic ideas. If you want some more, have a look here, it was his latest creation and it stormed the Indy community.