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. However, higher fuel prices and performance-car insurance surcharges deterred many buyers as the interest in high performance waned. International variants Canada (1960-1966) Chrysler Canada marketed the Valiant at Dodge and Plymouth dealers under a standalone "Valiant" marque. The Canadian 1960–62 Valiant was visually similar to its American counterpart except the badge on the trunk lid read "by Chrysler" instead of "Plymouth". Besides minor differences in interior and exterior trim, the alternator was an extra-cost option in Canada through 1962 while it was standard equipment in America. An anti-ice system for the carburetor's throttle body, engine block heater, battery warmer, electric car interior heater and other cold-climate items were available as factory or dealer-installed options. Air conditioning, which was first offered in the US 1961 models, was not made available north of the border until 1966. Some Canadian-made Auto-Lite (now Prestolite) electrical components were used in lieu of the American-production Chrysler-built components. The Windsor, Ontario, plant was a source for left- and right-hand-drive export Valiants as knock down kits. For 1963 and 1964, the Canadian Valiant used US Plymouth Valiant front sheet metal with the US Dodge Dart body and wheelbase (except wagons, which—like all 1963–1966 Dart and Valiant wagons—were on the wheelbase). For 1965, Chrysler Canada sold both the wheelbase and the wheelbase A-body vehicles, all badged as Valiants, and all with the US Dart dashboard and instrument cluster. For 1966, the shorter Valiant was dropped from the Canadian market and all Canadian Valiants were now rebadged US Darts. The Canadian Barracuda, badged as the "Valiant Barracuda", was built in Canada in 1964 and 1965 but was imported for 1966. Like the Valiant, the Barracuda had no Plymouth markings. With the coming of the US-Canada Auto Pact of 1965, Chrysler could ship cars and parts both ways over the border and in 1967 the company began importing Plymouth Valiants and Dodge Darts from the US, as well as exporting Darts and Valiants from Windsor to the US.