New compact model body named E21, which replaced the BMW 2002
and initiated the beginning of 3 series, was introduced in July 1975. It has a lot of technological and other changes: increased interior space, improved fuel economy system, better passengers safety and more.
Originally E21 comprised four modifications of 3 series: 316, 318, 320 and 320i (similar to BMW 2002 modifications). United States only allowed the import of one modification - 320i, which satisfies orders of tough laws regulating the engine emissions.
Most of E21 modifications produced until 1983 (except for some models which remained in production until 1985) and was replaced by a new generation - BMW 3 series E30