The 1974 Camaro grew seven inches (178 mm) longer thanks to new aluminum bumpers required to meet federal standards and a forward sloping grille. Round taillights were replaced with a rectangular wraparound design. It was the last year to have a flat rear window, with thick roof pillars. All later years had slimmer roof pillars and a wrap around rear window for better visibility.
Camaro sales increased to over 150,000 unit despite the energy crisis fueled by the Arab Oil Embargo. Two ponycar competitors left the stable this year as Ford downsized the Mustang to a subcompact based on the Pinto and Mercury upsized its Cougar to an intermediate-sized personal luxury car to compete with the Chevrolet Monte Carlo and Pontiac Grand Prix. Chrysler Corporation would discontinue the Plymouth Barracuda and Dodge Challenger during the course of the 1974 model year and American Motors would drop the Javelin at the end of the year. During the mid-to-late 1970s, the Camaro and similar Pontiac Firebird would have the traditional ponycar market all to themselves and score record sales in the process.
Source: Wikipedia, 2011