Mitsubishi Saturn engine

The Mitsubishi Saturn or 4G3 engine is series of overhead camshaft (OHC) straight-four internal combustion engines introduced by Mitsubishi Motors and saw first service in the 1969 Colt Galant. Displacement ranges from 1239 to 1755 cc, although there was also a rare 1994 cc inline-six version built from 1970 until 1976. The early versions have chain driven valvetrain while the later versions are belt driven and equipped with balance shafts.

4G30
The 4G30 displaces 1289 cc. It is an 8-valve SOHC design with an aluminium head and iron block. The engine has five main bearings. Power was 87 hp.

Bore x Stroke: 73x77 mm

Applications

 * 1969.12-1971.09 Mitsubishi Galant A I (A51)

4G31
The 4G31 displaces 1499 cc. It is an 8-valve SOHC design with an aluminium head and iron block. The engine has five main bearings. Power was 95-105 hp depending on which carburetor combo was used. An updated version with central-point electronic fuel injection was installed in Mirages and Lancers from 1986 on. A version for industrial use has 37 PS at 3000 rpm.

Bore x Stroke: 74.5x86 mm

Applications

 * 1969.12 – 1971.09 Mitsubishi Galant A II, A III (A52)
 * 1986–1987 Mitsubishi Mirage
 * Mitsubishi FG20 Forklift

4G32
In 1970, the 4G32 was introduced, and it displaces 1597 cc. It is an eight-valve SOHC design with an aluminium head and iron block. The engine has five main bearings, a cross flow head and a single down draught carburetor. Firing order is 1-3-4-2. The GSR versions used two twin-barrel Mikuni-built Solex carburetors for a total of 110 hp (SAE).



A version with an early iteration of Mitsubishi's MCA lean-burn system (MCA-IIB), fulfilling the intermediate Japanese exhaust regulations for 1975, was called G32A. This was built for less than one year, as the new MCA engine arrived in November 1975. Those with the later, cleaner yet, "MCA-Jet" system were called G32B. Later, the G32B also came in a fuel injected, turbocharged model. For competition, a version of the 4G32 engine was made with a DOHC eight-valve cylinder head, and fitted with two twin-choke 40 mm Solex sidedraft carburettors.

Bore x Stroke: 77x86 mm


 * Mitsubishi Celeste
 * Mitsubishi Galant
 * Mitsubishi L200
 * Mitsubishi L300
 * 1973.02 – 1979.03 Mitsubishi Lancer (A73A)
 * 1977.06 – 1979.03 Mitsubishi Lancer (A144A, G32B)
 * 1975.03 – 1979.06 Mitsubishi (Lancer) Celeste (A73A)
 * 1975.03 – 1975.11 Mitsubishi (Lancer) Celeste (A77A, G32A)
 * 1977.07 – 1981.07 Mitsubishi (Lancer) Celeste (A144, G32B)
 * 1980–1987 Mitsubishi Lancer EX (A174A)
 * Mitsubishi Galant Lambda/Sapporo
 * Mitsubishi Sigma
 * Mitsubishi Sapporo
 * Mitsubishi Cordia
 * Mitsubishi Tredia
 * Mitsubishi Mirage
 * Dodge Colt
 * Eagle Vista Turbo
 * Hyundai Pony
 * Hyundai Stellar
 * Mazda Familia
 * Plymouth Arrow

4G32T
Turbocharged version of the 4G32.

4G33
The 4G3 displaces 1440 cc from a 73x86 mm bore and stroke. There was also an MCA-Jet equipped G33B developed to fulfill the 1978 Japanese emissions regulations.


 * Mitsubishi Celeste
 * 1979.06-1989.01 Mitsubishi Delica
 * Mitsubishi Galant
 * 1973.02-1977.06 Mitsubishi Lancer (A72A)
 * 1977.06-1978.04 Mitsubishi Lancer (A143A, G33B)
 * 1973.09-1979.03 Mitsubishi Lancer (A72V)
 * 1975.03-1977.06 Mitsubishi (Lancer) Celeste (A72A)
 * 1977.07-1978.03 Mitsubishi (Lancer) Celeste (A143, G33B)
 * Hyundai Pony
 * Hyundai Stellar
 * Plymouth Arrow
 * Mitsubishi FG15T Forklift (1979)

4G35
The 4G35 displaces 1686 cc. It is an 8-valve SOHC design with an aluminium head and iron block. The engine has five main bearings. Power was 105-115 hp depending on which carburetor combo was used.

Bore x Stroke: 79x86 mm

Applications:
 * 1973.01-1973.06 Mitsubishi Galant GS (A55)
 * 1972.02-1976 Mitsubishi Galant GTO (A55C)

4G36
The 4G36 displaces 1239 cc. 73x74 mm bore and stroke.

Applications:
 * Mitsubishi Celeste
 * Mitsubishi Colt
 * Mitsubishi Lancer

4G37
The 8-valve SOHC 4G37 displaces 1755 cc.

Bore x Stroke: 80.6x86 mm

Compression Ratio: 9.5:1

Applications: By other brands:
 * Mitsubishi Chariot/Space Wagon 1983–91
 * Mitsubishi Cordia
 * Mitsubishi Galant
 * Mitsubishi Eclipse 1990–1994
 * Mitsubishi Lancer/Lancer Fiore/Mirage - 4WD only
 * Mitsubishi Tredia
 * Eagle Talon DL 1993–1994
 * Plymouth Laser 1990–1994

6G34
The 6G34, referred to by Mitsubishi as the Saturn 6, is a 12-valve SOHC straight-6 of 1994 cc displacement.

The 6G34 was used only in the Mitsubishi Debonair Executive from September 1970 to June 1976, and saw very limited production. Effectively, the design was that of the standard Saturn four-cylinder block with two additional cylinders grafted on to replace the KE64.

Applications:
 * Mitsubishi Debonair 1970.09-1976.06 (Japan only)