Through its lifespan, Subaru's minicompact was perhaps best known for its available electronically controlled variable-transmission. Dubbed ECVT, it offered an infinite spread of gear ratios. Although the basic idea had surfaced decades earlier, and was used on the Dutch-built DAF in the 1960s, Subaru was unique for offering it in the U.S. market at this time. Introduced in early 1987, the Justy initially came only as a 2-door hatchback. A 4-door hatchback joined for 1990, on the same 90-inch wheelbase. Both came with either front-wheel drive or on-demand 4-wheel drive. All models except the base Justy got a 73-horsepower fuel-injected engine for 1990, instead of the carbureted 66-horsepower 3-cylinder. Fuel-injected models got a new intermediate front driveshaft to help reduce "torque steer." A new "Fun Justy" appearance package was introduced for the 2-door model. Having debuted in 1989, the ECVT unit was now available on 4WD models as well as those with front-drive. With ECVT, a metal belt connects two pulleys that continuously vary the ratio of engine speed to driveshaft speed. Operation can be described as similar to a dimmer switch, as opposed to a 3-way light switch. Justy also was available with an ordinary 5-speed manual transmission.