The
Can Am Series folds by mid decade due to the Oil Crisis and dominance of McLaren and Chevrolet. It is revived in 1977 based on
Formula 5000, but folds shortly afterward.
Formula 5000 continues to be popular until mid-decade, when it declines into the basis for the new Can-Am
The Grand National becomes the Winston Cup Series after a purchase from
Winston Cigarettes. Due to the Oil Crisis it is forced to allow even more modifications to its cars, beginning the departure from its strictly stock roots.