Chevrolet Impala (fifth generation, 1971 to 1976)

The fifth generation Impala, redesigned for 1971, was the largest car Chevrolet had ever offered. Power fell year by year as emissions rules and unleaded fuel arrived, front disc brakes were standard from 1971, the last Impala convertible was sold in 1972 and the pillarless Sport Coupe was dropped after 1975. Its model years run from 1971 to 1976. The Turbo Jet 454 big block remained available through the early years and power fell each year, the last Impala convertible was sold in 1972, and from 1972 all engines were designed to run on unleaded gasoline.