The Mitsubishi Astron or 4G5/4D5 engine, is a series of straight-four internal combustion engines first built by Mitsubishi Motors in 1972. Engine displacement ranged from 1.8 to 2.6 litres, making it one of the largest four-cylinder engines of its time.

The Mitsubishi Lancer (A70) is the first generation version of Mitsubishi's long-running Lancer nameplate. When introduced in 1973, it filled the gap between the Minica kei car and the considerably larger Galant. It was a replacement for the Colt 1200, last sold in 1970. Although sedan production ended in 1979, vans continued on until 1985. This Lancer also formed the basis for the Lancer Celeste sports coupé of 1975 through to 1981. These Lancers were sold under a multitude of names in different markets.