The Mitsubishi 4G9 engine is a series of straight-4 automobile engines produced by Mitsubishi Motors. All are 16-valve, and use both single- and double- overhead camshaft heads. Some feature MIVEC variable valve timing, and it was the first modern gasoline direct injection engine upon its introduction in August 1996.

4G91

The 4G91 uses a bore and stroke of 78.4x77.5 mm for a total displacement of 1496 cc. With a 9.5:1 compression ratio and DOHC, four-valve-per-cylinder head and multi-point EFI, this engine produces 115 PS at 6,000 rpm and 135 Nm at 5,000 rpm. The 4G91 was a short-lived model, mainly built between 1991 and 1995 and rarely seen in export markets. There was also a carbureted model, with 97 PS at 6,000 rpm and 126 Nm at 3,500 rpm. Applications

4G92

The 4G92 displaces 1597 cc. It first appeared in the late-1991 Japanese-spec Mirage RS and Super R in DOHC form. The 4G92 is basically a version of the 4G91 with the bore increased to 81 mm. In the original DOHC 16V form it produces 120 PS. Later, a fuel-efficient SOHC version was added, but the 4G92 is best known in its high-performance MIVEC equipped DOHC version, which fully replaced "ordinary" DOHC in 1993. Power output was raised as high as 170 PS, as found in the JDM Mirage Cyborg-ZR and 1992 Lancer MR, making it one of the most powerful 1.6-litre naturally aspirated engines. A modular displacement (MD) version of the 4G92 MIVEC was also produced – MD is Mitsubishi's cylinder deactivation system which helps improve fuel consumption. 4G92P SOHC 16 Valve 4G92 DOHC 16 Valve 4G92-MIVEC DOHC 16 Valve Applications

4G93

The 4G93 is a 1834 cc engine available in both SOHC and DOHC versions. Turbocharged variants are also produced. In mid 1996 Mitsubishi released a gasoline direct injection (GDI) version of the 4G93. This GDI model saw a production of over a million units though it was a heavy polluter therefore only sold in the Japanese market. A partially cleaned up version (with less power) was later sold in Europe, and was among the first of the modern GDI engines. It brought good fuel economy and, if well serviced, long engine life. 4G93 SOHC 16 Valve MPI 4G93 SOHC 16 Valve Carburetor 4G93 DOHC 16 Valve MPI 4G93T DOHC 16 Valve Turbo 4G93 DOHC 16 Valve GDI 4G93 DOHC 16 Valve GDI Turbo Applications

4G94

The 4G94 is a 1999 cc version built in Japan, used in the Mitsubishi Lancer. It has a cast iron engine block with Multi-point fuel injection and an aluminum SOHC cylinder head with forged steel connecting rods and four valves per cylinder. The 4G94 Also comes in the GDI DOHC variant which can be found in the Mitsubishi Galant. 4G94 SOHC 16 Valve MPI 4G94 DOHC 16 Valve GDI Applications Applications