Sports racers were growing in popularity by the mid-1960s. The Group 7 sports racers were the Big Boys. They had very few technical restrictions. No homologation requirements. Engine capacity was unrestricted. Forced induction was allowed. No aerodynamic restrictions, for all intents and purposes. It was essentially a free-for-all. Group Seven became the foundation for the SCCA Can-Am series, inaugurated in 1966. The series was named Can-Am because of it's two races in Canada and four races in the United States of America. The series was very popular, and drew large prize money, which only fueled its popularity over the years. By 1973, the series produced some of the most irrational cars motorsports has ever seen.
In many ways, the Chaparral 2E was the first step in that direction.