Chrysler increased the displacement of its highest-performance small block V-8 engine from to for 1974. The 360 was rated at and placed in the Duster 360. However, the 1974 Duster was nearly heavier than the 1971 model on account of the heavier bumpers, side-impact door beams, emission control equipment, and added soundproofing. Even with performance options such as the four-speed manual transmission, Hurst shifter and Sure-Grip differential with 3.55:1 axle ratio, 0–60 mph and quarter-mile times increased roughly two seconds compared to those for the 1970 Duster. Unfortunately, higher fuel prices and performance-car insurance surcharges deterred many buyers as the interest in high performance waned. However, throughout its production, the most popular engines in Dusters were the 198 and 225 cubic-inch Slant Sixes.