For 1974, Plymouth replaced the 340 with a 360 cu in (5.9 L) version of the corporate LA-series V8, with lower performance due to U.S. government-imposed emissions regulations. The 1974 "E58" 360 engine produced 245 hp (183 kW). New retractable front seat belts were added. In the midst of the first oil crisis, 1974 would be the Duster's best sales year, with a total of 281,378 Duster-bodied cars produced.
Source: Wikipedia, 2012