The Mitsubishi Saturn or 4G3 engine is series of overhead camshaft (OHC) straight-four internal combustion engines introduced by Mitsubishi Motors and saw first service in the 1969 Colt Galant. Displacement ranges from 1.2 to 1.8 L (1,239 to 1,755 cc), although there was also a rare 2-litre (1,994 cc) inline-six version built from 1970 until 1976. The early versions have chain driven valvetrain while the later versions are belt driven and equipped with balance shafts.