| Mitsubishi 6G7 engine | |
| Manufacturer: | Mitsubishi Motors |
| Production: | 1986–2021 |
| Weight: | around 1550NaN0 |
| Valvetrain: | SOHC 2 valves × cyl. DOHC 4 valves × cyl. with MIVEC (on some versions) |
| Displacement: | NaNcc |
| Bore: | 74.7mm 83.5mm 91.1mm 93mm 95mm |
| Stroke: | 76mm 85.8mm 90mm |
| Configuration: | 60° V6 |
| Turbocharger: | with intercooler (on some versions) |
| Supercharger: | On Debonair only. |
| Compression: | 8.0–10.5:1 |
| Fueltype: | Gasoline |
| Fuelsystem: | Multi-port fuel injection Direct injection |
| Coolingsystem: | Water-cooled |
| Oilsystem: | Pressure feed, full-flow filtration with Trochoid type oil pump |
| Power: | NaN0NaN0 |
| Torque: | NaN0NaN0 |
| Successor: | Mitsubishi 6B3 engine |
The 6G7 series or Cyclone V6 engine is a series of V6 piston engines from Mitsubishi Motors. Five displacement variants were produced from 1986 to 2021, with both SOHC and DOHC, naturally aspirated and turbo charged layouts. While MIVEC variable valve timing has also been implemented in some versions the 2.5, 3.0, and 3.5 L versions were also available with gasoline direct injection. This engine has been the flagship powerplant of the company except when they briefly built a V8 in 1999–2001. The staple of their high-end sedans, it was given twin-turbos for the Mitsubishi GTO, and became the most powerful car ever built by the company at the time.
| Engine code | Displacement | Bore × stroke | |
|---|---|---|---|
| 6G71 | 1998cc | NaNmm | |
| 6G72 | 2972cc | NaNmm | |
| 6G73 | 2497cc | NaNmm | |
| 6G74 | 3497cc | NaNmm | |
| 6G75 | 3828cc | NaNmm |
The 6G71 model featured SOHC and produced 880NaN0 at 5,500 rpm and 172Nm at 4,500 rpm. It was installed with two valves per cylinder, and used Mitsubishi's ECI-Multi multiple port fuel injection fuel delivery system. The compression ratio was 8.9:1. An earlier version, with single-point fuel injection, only had 1050NaN0 at 5,000 rpm and 16.10NaN0 at 4,000 rpm.[1]
A supercharger was installed and exclusive to the Debonair. It produces 1500NaN0 at 5,000 rpm and 221Nm at 3,000 rpm. The compression ratio for the supercharged model is 8.0:1. The 6G71 engine was also converted to run on LPG, a version which was only available to the Debonair and mainly intended for commercial (taxi) use.
The 6G72 was manufactured in three different models which featured SOHC with 12 valves, SOHC with 24 valves, and DOHC with 24 valves.
The latest version was used in the Mitsubishi Eclipse GT and Galant. Output in 2004 was 2100NaN0 at 5500 rpm with 278Nm of torque at 4000 rpm. In the older version, used in many Chrysler models since 1987, this V6 was an SOHC 12-valve developing 1410NaN0 at 5000 rpm and 1720NaN0 of torque at 3600 rpm. The Mitsubishi models were with a 3.0L 6G72 engine SOHC 24-valve developing 1950NaN0 at 5000 rpm and 2050NaN0 of torque at 4000 rpm. For the MIVEC engine, output was 2730NaN0 at 6000 rpm and 3040NaN0 at 4500 rpm.
The SOHC 12-valve for the second generation of Pajero could produce up to 1090NaN0 and 2350NaN0, whereas the SOHC 24-valve could produce up to 1330NaN0 and 2550NaN0.
The DOHC 24-valve was used in the Mitsubishi Debonair, 3000GT, and Dodge Stealth producing 2220NaN0 and 205lbft of torque with a 10.0:1 compression ratio in naturally aspirated form, and as much as 3200NaN0 and 315lbft of torque in turbocharged form.[2] The turbocharged variant had the lowest compression ratio at 8.0:1, with each bank of the V6 having its own independent turbocharger and intercooler. Turbochargers were built by Mitsubishi.
The 6G73 is a 24-valve SOHC design with two valves running off a single cam lobe on the exhaust valves using a forked rocker arm and each intake valve actuated with two cam lobes, with a smaller bore than the 3.0L version of the same block. Bore and stroke are 83.5x; it is a 60-degree V6 and weighs around 1550NaN0. The engine has low-profile cast aluminum heads which help it to fit into compact engine bays, while pent-roof combustion chambers increase efficiency and make room for four valves per cylinder, arranged in a cross-flow pattern with a "tumble" intake port for both strong breathing and low emissions. Spark plugs are centered in the combustion chambers. The intake valves are 332NaN2 in diameter while exhaust valves are 292NaN2. The SOHC 24 valve version of the 6G72 uses these same cylinder heads. A toothed timing belt is used. The output of 6G73 is 1630NaN0 at 5,900 rpm with 2210NaN0 of torque at 4,350 rpm.[3]
The 6G74 is a 24-valve unit available with either SOHC, DOHC, or MIVEC DOHC. Output for the SOHC version varies from 1390NaN0 at 4,750 rpm with 3060NaN0 of torque at 3,750 rpm in the Pajero to the highest output of 1640NaN0 at 5,250 rpm with 3180NaN0 of torque at 4,500 rpm in the Australian-made Magna Sports, VR-X and Verada GTV/GTVi and 1800NaN0 at 5,500 rpm with 3330NaN0 of torque at 4,000 rpm in the Magna Ralliart. For the MIVEC, only available in the Mitsubishi Pajero Evolution, the output is 2090NaN0 at 6,000 and 324Nm at 4,500 rpm. It uses Multi-port fuel injection and uses forged steel connecting rods.
The gasoline direct injection version of the 6G74 was launched in April 1997 as the first GDI V6 engine ever produced. It differed from the basic 6G74 in many ways apart from its unique fuel injection system—it had a crown-curved rather than flat piston head, upright intake ports rather than angled, and a 10.4:1 rather than a 10.0:1 compression ratio. Mitsubishi claimed 30 percent better fuel economy, a 30 percent reduction in emissions, and higher power outputs than diesels.[4]
The 6G75
5. https://media.mitsubishicars.com/channels/2004-Galant/releases/d8fa6a4a-5172-57cd-7b04-a59f4b06fbf0