the "MCA-Jet" high-swirl system. For 1978 a new Dodge Colt wagon was the larger, rebadged Mitsubishi Galant Sigma. The 1.6-litre MCA-Jet four as the smaller sedans and coupes was standard with the 2.6-litre, Astron engine optional as well as a five-speed manual transmission. While the last year for the Lancer-based Colts was 1979, the wagon was continued alongside the front-wheel drive Mirage-based fourth generation models until 1981 when it was effectively replaced by the domestic Dodge Aries K wagon. The larger Mitsubishi Galant Lambda coupé was also marketed as the Dodge Colt Challenger from 1978, although the "Colt" part was later dropped. It shared the chassis as well as the engine options of the Colt wagon. Fourth generation (1979-1984) From late-1978 for model year 1979, the Dodge Colt and Plymouth Champ nameplates were applied to the front-wheel-drive Mitsubishi Mirage imports into North America. The Colt and Champ (Plymouth Colt after 1982) as a 3-door hatchback, and came in Deluxe or Custom equipment levels. These imports used a Mitsubishi Orion 4G12 1.4-liter overhead-cam, four-cylinder engine at first, which received the highest United States Environmental Protection Agency fuel economy rating in its debut year. This engine was joined by the 1.6-liter, 4G32 Saturn engine at the end of the year. For 1981, a bare bones "low-line" version was introduced. An RS package also became available, with stiffer suspension, sportier interior with extra gauges, and a larger fuel tank. There were three manual transmissions and one automatic transmission available. There was a KM110 four-speed manual transmission or a "Twin Stick" (Mitsubishi Super Shift) version of the transmission that used a two-speed transfer case to give 8 forward and 2 reverse speeds. There was also the option of a KM119 five-speed manual transmission or a TorqueFlite three-speed automatic transmission. For 1982 a five-door hatchback joined the lineup. The names of the equipment levels changed to "E" and "DL". At some point claimed power dropped to 64 and 72 hp respectively for the small and large engines, while the 1.6 was only available with the automatic transmission. In August 1983, for the 1984 model year (which was to be the last year of this model of Colt), the GTS Turbo model arrived along with a naturally aspirated GTS package, similar to the earlier RS one. Unique for North America - the turbocharged Colt/Mirages sold elsewhere had a 1.4-litre engine - this used the fuel-injected 1.6-litre