The Mitsubishi KE engine is a range of engines produced by Mitsubishi Motors during the 1960s and early 1970s. They were extensively used in the various Colt-branded vehicles the company produced from 1963.
The engines were overhead valveiron-blocks, some for petrol and some for gasoline use. The first digit after the KE denotes the number of cylinders, straight-4s becoming KE4 and six-cylinder versions such as the single overhead camshaft 2.0 L straight-6 which was developed in 1964 for the new Mitsubishi Debonair flagship sedan, receiving the KE6 prefix. The last digit is simply a serial, denoting which number engine it is. Some of these engines, such as the two-liter KE42, were further developed into overhead-cam engines and were named Astron.
In 1973, the KE42 was upgraded to meet new emissions regulations and received the MCA (Mitsubishi Clean Air) name to reflect this. Power also increased by 5 horsepower. This engine was developed into an overhead-cam unit, called the Astron 4G52.