Mitsubishi 4G1 engine

The Mitsubishi Orion, or 4G1, is a series of inline-four internal combustion engines introduced by Mitsubishi Motors in around 1977 alongside the Astron, Sirius and Saturn, and first used in the Colt and Colt-derived models in 1978. Displacement ranges from 1.2 to 1.6 litres. It replaced the Neptune and carried over that engine's layout and crossflow design, but unlike the near-square Neptune it was a long-stroke design. The 4G11 used the MCA-Jet lean-burn head with a tiny second inlet valve, and the 4G12 was the first to use Mitsubishi's modulated displacement technology. The 4G15 became one of the longest-lived Japanese engines and is still built in China.