This story originally appeared in the October 2016 edition of SPEED SPORT Magazine.

Roll the clock back more than 50 years. You’re standing at the fence as 20 big-block-powered race cars roll toward the starter’s stand. The green flag waves and all hell breaks loose. It’s the type of thunder only the Can-Am cars could make. Those were the halcyon days of American road racing for fans and competitors alike.

The Can-Am got its name because the initial races ran in Canada and the United States. The first rule in the FIA Group Seven rulebook was: There are no rules. OK, there were precious few. The cars had open cockpits, covered wheels and safety equipment such as roll bars, onboard fire systems and competition racing harnesses. The SCCA added a two-seat requirement to make them “sports cars.” There were no engine, chassis, aerodynamic or weight restrictions. Turbos and superchargers were permitted.

The cars were faster than Formula One cars at many tracks, adding to their appeal for both drivers and fans.

Innovation was a Can-Am hallmark. And that’s exactly what Jim Hall did with his Chaparral race cars. Hap Sharp and Texas oil man Hall led the charge with a corral full of advanced designs. Hall had a covert relationship with Chevrolet engineers on many aspects of his car’s evolution. They explored the frontiers of chassis and drivetrain design, aerodynamics and even probed the science of data acquisition.

The aerodynamic barriers were first broken with the Kamm tail Chaparral 2A and continued with the development of the high-mounted movable rear wing. Thanks to the General Motors-designed semi-automatic transmission, the driver could change the rear wing’s angle of attack with his left foot. The wing could be flattened to decrease aerodynamic drag on the straights, then tilted down to add cornering down force or flipped straight up to add braking force.

Hall also pioneered ground effects in racing by creating a vacuum under the car, increasing down force with a minimal drag penalty. The Chaparral 2J was the ultimate example. The 2J — “the sucker car” — had a second snowmobile engine to power two fans that sucked the air out from the bottom of the car. This technology was quickly banned because competitors were peppered with debris that was sucked up by the fans.

The Can-Am series flourished during the 1970s largely due to the Johnson’s Wax sponsorship. David Hobbs suited up sporadically. “It was a good series,” Hobbs said, “and there were interesting cars. It attracted the best of the best because we had quite a few Formula One drivers.”

Hobbs says that’s because the money was better in Can-Am than Formula One as a result of the Johnson’s Wax race purses.

Formula One luminaries John Surtees, Jody Scheck­ter, Jackie Stewart, Mario Andretti, Jack Brab­ham and Peter Revson turned up. Parnelli Jones, Bruce McLaren, Denny Hulme, George Follmer, Mark Donahue, Dan Gurney and Vic Elford joined them.

Race car manufacturers jumped on the Can-Am glory road, too. BRM, Ferrari and McKee were quickly overshadowed by Lola and McLaren. Surtees won the first championship in a Lola T-70 and McLaren followed with the next five in a row. The burnt orange cars of Bruce McLaren and Hulme dominated every race, invariably finishing 1-2. The series earned the “Bruce and Denny Show” nickname as a result. That ended after McLaren was killed in a 1970 testing crash.

Surprisingly, the McLaren dominance didn’t create the usual ruckus.

“It’s always been a fascinating question for me because every time someone like Ferrari and Michael Schumacher wins a championship year after year and people say, ‘My God how boring,’ and when Mercedes wins three championships in a row and people say, ‘My God how boring,’” Hobbs said. “The McLaren won every race for five years and everybody says what a marvelous series it was and how fantastic the cars were. It seems to attract such amazing nostalgia, but was it such a great series?”

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