Only the fifth generation Diamante, Debonair, and Galant were equipped with the Mitsubishi 6G71 2.0-liter 12-valve V6 engine, which was manufactured from 1986 to 1992. There were versions with a Mikuni compressor, gas, and distributed or single injection.
The engines 6G72, 6G72TT, 6G73, 6G74, and 6G75 are also part of the 6G7 family.
The engine was mounted on:
- Mitsubishi Debonair 2 (S1) in 1986 – 1992;
- Mitsubishi Diamante 1 (F1) in 1990 – 1992;
- Mitsubishi Galant 5 (E1) in 1986 – 1990.
Specifications
| Production years | 1986-1992 |
| Displacement, cc | 1998 |
| Fuel system | single injection (SPI SOHC) distributed injection (MPI SOHC) distributed injection (6G71-T Supercharger) |
| Power output, hp | 105 (SPI SOHC) 120 – 125 (MPI SOHC) 150 (6G71-T Supercharger) |
| Torque output, Nm | 158 (SPI SOHC) 172 (MPI SOHC) 221 (6G71-T Supercharger) |
| Cylinder block | cast iron V6 |
| Block head | aluminum 12v |
| Cylinder bore, mm | 74.7 |
| Piston stroke, mm | 76 |
| Compression ratio | 8.9 (SPI SOHC) 8.9 (MPI SOHC) 8.0 (6G71-T Supercharger) |
| Features | SOHC (SPI SOHC) SOHC (MPI SOHC) SOHC, intercooler (6G71-T Supercharger) |
| Hydraulic lifters | yes |
| Timing drive | belt |
| Phase regulator | no |
| Turbocharging | no (SPI SOHC) no (MPI SOHC) Mikuni DM51 (6G71-T Supercharger) |
| Recommended engine oil | 5W-40 |
| Engine oil capacity, liter | 4.3 |
| Fuel type | petrol |
| Euro standards | EURO 1 (SPI SOHC) EURO 2 (MPI SOHC) EURO 2 (6G71-T Supercharger) |
| Fuel consumption, L/100 km (for Mitsubishi Debonair 1989) — city — highway — combined |
14.3 9.1 11.0 |
| Engine lifespan, km | ~300 000 |
| Weight, kg | 190 |
Disadvantages of the Mitsubishi 6G71 engine
During the initial years of production, the motors were damp and caused numerous issues.
After that, the quality improved, and the owners’ complaints were frequently limited to oil usage.
Since the liners are common, it’s important to pay attention to the lubrication level.
Contamination of the throttle or idle speed controller is the primary cause of floating speed.
Hydraulic lifters and an unreliable ignition system are among its weaknesses.