The Canadian-American Challenge Cup or CanAm, was an SCCA/CASC sports car racing series from 1966 to 1974. A second generation of Can Am followed, but this was a fundamentally different series based on obsolete Formula 5000 cars with sports car bodies.
Can Am started out as a race series for Group 7 sports racers with two races in Canada (Can) and four races in the US (Am). The series was initially sponsored by J-Wax. The Series used FIA Group 7 rules which had a rule structure with very few restrictions on innovation. Those rules allowed virtually unlimited experimentation with engine power, displacement, turbocharging and chassis downforce which resulted by its end it in truly outrageous cars with well over 1000 horsepower (750 kW), wings, active downforce generation, very light weight and unheard of speeds.
Notable drivers and technology
Notable drivers in the original Can Am series included virtually every acclaimed driver of the late 60's and early 70's. Denny Hulme, Bruce McLaren, Phil Hill, Mark Donohue, Jim Hall, Chris Amon, Dan Gurney, Peter Revson, Masten Gregory, John Surtees, Parnelli Jones, Mario Andretti, Jack Brabham, Pedro Rodriguez, Vic Elford, and Jackie Stewart all drove Can Am cars at one time or another.
Can Am was the birth place and proving ground for (what was at the time) outrageous technology. Can Am cars were among the first race cars to sport wings, effective turbo charging, undertrays, and aerospace materials like titanium. This led to the eventual downfall of the original series when costs got very much out of hand, but during its height Can Am cars were at the cutting edge of racing technology. Noted constructors in the Can Am Series included McLaren, Chaparral, Lola, BRM, Shadow and Porsche.
Team McLaren cars were specially designed race cars. The Can Am cars were developments of the sports cars which were introduced in 1964 for the North American sports car races. The development variants M1A and M1B were raced as factory cars in the 1966 with Bruce McLaren and Chris Amon as drivers. In 1967, specifically for the Can Am series, the McLaren team introduced a new model, the M6. The McLaren M6 also introduced what was to become the trademark orange colour for the team. The McLaren team consisted of team owner and leader Bruce McLaren and Dennis Hulme. The M6 series were a full alumninum monocoque design with no uncommon features but, for the time, uncommon attention to detail. The M6 series of cars were powered by smallblock Chevy engines built by George Boltoff for McLaren and were the model of reliability. This was followed in 1968 by the M8A, a new design based around the Chevy "big block" engine as a stressed member of the chassis. The M8B, M8C, M8D and M20C were developments of that aluminum monocoque chassis. McLaren so dominated the 1968-1971 seasons that Can Am was often called the "Bruce and Denny Show" after the drivers. Sadly, Bruce McLaren lost his life in 1970 at Goodwood when the rear bodywork of his M8C detached during testing resulting in a totally uncontrollable car and a fatal highspeed crash. Team McLaren went on to become a several time F1 champion and is still very much a part of F1.
Jim Hall's Chaparrals were very innovative, following his success in the United States Road Racing Championship (USRRC). Jim Hall's 2 series Chaparrals were leaders in the application of aerodynamics to racecars culminating with the introduction of the 2E in 1966, the first of the high wing race cars. The 2E was a defining design, and the 2G was a development of that basic design. The FIA banned movable wings and Chaparral responded with the 2H 1969. The 2H broke new ground, seeking to reduce drag but didn't achieve much success. The 2J that followed was perhaps the ultimate example of what Group 7 rules could allow in a racing car. It was a twin-engined car, with the by-then usual big-block Chevrolet engine providing the driving force, and a tiny snowmobile engine powering a pair of fans at the back of the car. These fans, combined with rubber 'skirts' around the bottom of the car created an vacuum underneath the car, effectively providing the same level of downforce as the huge wings of previous vehicles, without the drag. Although far too mechanically complex to survive in racing environments, the theory was sound, and would appear in Formula One a few years later, first in Colin Chapman's Lotus cars, and even more directly in the Brabham BT46 'Fan Car' of 1977.
The Porsche 908 spyder was used in Can Am, but was underpowered (350 hp) and mainly used by underfunded teams. It did win the 1970 Road Atlanta race though. The 917PA, a spyder version of the 917K Le Mans car, was raced, but its normally aspirated flat-12 was underpowered (530hp). In 1971 the 917/10 was introduced. This was still not turbocharged, but was lighter and had cleaner body work, and Jo Siffert managed to finish fourth in the championship. For 1972 the 917/10K with a turbo charged 900 horsepower 5 liter flat-12 was introduced. Prepared by Roger Penske and driven by Mark Donohue and George Follmer these cars won six of the nine races. In 1972 Porsche introduced an even more powerful car, the 917/30. Nicknamed the Turbopanzer this car was truly a monster. With 1100 horsepower (820 kW) on tap from a 5.4 liter flat-12 and better downforce this car won every race in the 1973 championship. In 1975 Mark Donohue drove this car to a closed course world speed record of 221 mph (356 km/h) at the Talladega Superspeedway. It did over 250 mph (402 km/h) on the straights. It also helped kill Can Am by being one of the most expensive cars Porsche ever made. No one could compete with this outrageous machine with the budgets of the day. For 1974 a 3 miles per US gallon maximum fuel consumption rule was introduced but the SCCA, partially due to the current fuel crisis, but also to try and take the teeth out of Porsche's dominance. The 917/30 only raced once that year
1974 was the last year for the Can Am championship. Spiraling costs, a recession in North America following the oil crisis, and dwindling support and interest led to the series being cancelled the end of the 1974 season. The Can Am name still held enough drawing power to lead SCCA to introduce a revised Can Am series in 1977 based on rebodied chassis from the recently canceled Formula A/5000 series, but it never achieved the glory and success of the original.