The Canadian-American Challenge Cup, or Can Am, that ran between 1966 and 1974, was the pinnacle of least-rules-possible, no-holds-barred racing ever conceived. After Lola won the first title in 1966 with John Surtees driving, Bruce McLaren and Denny Hulme dominated for the next four years in McLaren cars, Bruce winning the title in 1967 and 1969 and Denny in 1968 and 1970. Peter Revson won in 1971 for McLaren and then Porsche came in with a development of the 917 racing car, the flat-twelve engine turbocharged to give up to 1100 horsepower, and swept all before it.
In 1970, a new make appeared, Shadow, but success remained elusive. The 1974 car, the DN4, was more successful. Briton Jackie Oliver won the series title, the last to be run to the original formula as started in 1966. Shadows were always run in a sinister jet black livery, thanks to the sponsor, UOP oil and The Shadow bag celebrates this.
