Mitsubishi 4G64

Mitsubishi 4G64 engine

  1. Specifications
  2. Overview, problems
  3. Performance tuning


Manufacturer Shenyang Aerospace Mitsubishi Motors Engine Manufacturing Co Ltd
Kyoto engine plant
Also called Sirius
Production 1983-present
Cylinder block alloy Cast-iron
Configuration Inline-4
Valvetrain SOHC
2 valves per cylinder
4 valves per cylinder
4 valves per cylinder
Piston stroke, mm (inch) 100 (3.50)
Cylinder bore, mm (inch) 86.5 (3.19)
Compression ratio 8.5

Displacement 2351 cc (111.9 cu in)
Power output 80 kW (112 HP) at 5,000 rpm
84 kW (124 HP) at 5,000 rpm
91 kW (132 HP) at 5,250 rpm
96 kW (150 HP) at 5,000 rpm
96 kW (150 HP) at 5,500 rpm
Torque output 184 Nm (114 lb·ft) at 3,500 rpm
189 Nm (120 lb·ft) at 3,500 rpm
192 Nm (128 lb·ft) at 4,000 rpm
214 Nm (133 lb·ft) at 4,000 rpm
225 Nm (133 lb·ft) at 3,500 rpm
HP per liter 48
Fuel type Gasoline
Weight, kg (lbs) 185 (330)
Fuel consumption, L/100 km (mpg)

Mitsubishi Eclipse III
10.2 (32)
7.6 (39)

8.8 (35)
Turbocharger  Naturally aspirated
Oil consumption , L/1000 km
(qt. per miles)
up to 1.0
(1 qt. per 600 miles)
Recommended engine oil 0W-40
Engine oil capacity, L (qt.) 4.0 (4.0)
Oil change interval, km (miles) 5,000-10,000
Normal engine operating temperature, °C (F)
Engine lifespan, km (miles)
-Official information

400,000+ (250,000+)
Tuning, HP
-Max HP
-No life span loss


The engine is installed in Mitsubishi Eclipse
Mitsubishi Galant
Mitsubishi L200/Triton
Mitsubishi Montero/Pajero
Mitsubishi Outlander
Mitsubishi Space Runner/RVR
Mitsubishi Chariot/Space Wagon
Mitsubishi Delica
Mitsubishi Magna
Mitsubishi Sapporo
Mitsubishi Starion
Mitsubishi Tredia
Mitsubishi Zinger
Brilliance BS6
Chery V5
Chrysler Sebring
Dodge Colt Vista/Eagle Vista Wagon
Dodge Ram 50
Dodge Stratus
Great Wall Hover

Mitsubishi 4G64 engine reliability, problems and repair

This large engine replaced the old 4G54, and had been created based on the 4G63; it also had a closed deck but had a different height of the block. Let’s learn about all the differences between 4G63 and 4G64. The engineers increased the deck height to 235 mm and installed a long-stroke crankshaft in this block with the piston stroke of 100 mm. The cylinder diameter was increased to 86.5 mm, and the length of connecting rods remained the same — 150 mm. This block also had balance shafts. The compression height of the pistons was 35 mm. All this provided 2.4 liters of displacement (2.35 liters, to be exact).
The crankshaft weighs is 15.8 kg, the pistons weigh is 354 g, and the connecting rods weigh is 623 g.

This block was covered with a SOHC 8-valve head. The compression ratio of these engines is 8.5:1, and the power is 112 HP at 5,000 rpm, the torque is 183 Nm at 3,500 rpm.
The cylinder head was later replaced by a 16 valve SOHC and the compression ratio increased to 9.5. This improved the performance and the power reached 145 HP at 5,500 rpm, the torque was 206 Nm at 2,750 rpm.
The injector size in such a 4G64 is 275cc. Later still, they started using a more modern DOHC 16V head with a compression ratio of 9:1.
The power increased to 156 HP at 6,000 rpm, the torque was 221 Nm at 4,000 rpm.
You can also find a 4G64 GDI under the hood of Mitsubishi Galant, Space Wagon, Space Gear, or Space Runner. These engines feature a SOHC 16V head with a direct injection system and an increased to 11.5 compression ratio.
The power of these engines is 150 HP at 5,500 rpm, and the torque is 225 Nm at 3,500 rpm.

All of these 4G64 heads are equipped with hydraulic lifters and you don’t have to worry about valve adjustment.

Mitsubishi 4G64 engine

Mitsubishi Galant 2,4L” by Polska821 / CC-BY 3.0 / Compressed from original

In all these engines, a timing belt is used that needs replacement at least once in 60,000 miles (90,000 km).
This engine belongs to the Sirius family along with other similar engines: 4G63, 4G63T, 4G61, 4G62, 4G67, 4G69, 4D65, and 4D68.
Since 2003, the successor of this engine called 4G69 has been produced. However, 4G64 are produced even today, but mainly for Chinese cars.

Mitsubishi 4G64 engine problems and malfunctions

Since this engine is nothing more than an enlarged 4G63, the problems of these engines are similar. It is very reliable, but it has problems with rough idle or vibrations, you can read about them in detail HERE.

Mitsubishi 4G64 engine tuning

DOHC head

If you want to go the non-turbo way, then your SOHC head should be thrown away. Instead, you need a G4JS DOHC head — such engines were installed in the following cars:

– 2000-2005 Hyundai Santa Fe
– 2000-2009 KIA Sorento
– 1998-2004 Hyundai Sonata
– 2000-2005 KIA Optima

The G4JS engine is an analog of your 4G64, but with a DOHC head. In addition to the head, you will need the entire intake and exhaust system. To this, you can add a cold air intake, an Evo throttle body, 272/272 camshafts + cam gears + valve springs, a Mitsubishi Galant fuel rail, 450cc fuel injectors, a more powerful fuel pump, and a 4-2-1 header, a 2.5″ exhaust system; besides, you should remove balance shafts. You can also buy forged internals to increase the compression ratio to 11.5.
All this needs configuring, and you will get close to 200 HP.
But if you are going to do such large-scale work, it would be better to use a turbocharged Evo head and the power will be much higher.


Now you will learn how to turbo the 4G64 and what main performance parts you will need for this.
There are two scenarios here:

 – 4G64 SOHC turbo
– 4G64+4G63 turbo

The first way is the easiest one; you just take your stock engine and install an Evo turbo. The compression ratio you have is low enough not to worry about problems.
Here are the several key performance parts you will need:

 – an Evo turbocharger
– an Evo header
– an Evo intercooler + pipes
– a 2.5″ exhaust system
– an Evo fuel pump or Walbro 255 lph
– 560cc fuel injectors (Evolution)
– a large radiator (e.g., Mishimoto)

Be sure to configure the ECU to work with these upgrades. Your new Evo collector will have to be adapted for the 4G64 engine, your stock internals can withstand about 300 HP at the crankshaft, and you need more? Then it’s a big risk.
Let’s consider the second way – a 4G64 with an Evo head. The result here will be much better! You will need a Mitsubishi Evolution head together with all its equipment.
The list of main OEM and aftermarket parts:

 – an Evolution head
– 150mm connecting rods (e.g., Manley)
– ARP rod bolts
– 87mm forged pistons
– an Evo intake system
– Evo spark plugs
– Evo ignition coils
– an Evo fuel system
– 750 cc fuel injectors
– a Walbro 255 fuel pump
– an Evo turbo
– an Evo header
– a 3″ exhaust system from the beginning to the end.

This way you can get 400 HP at the crankshaft and a faster spool than in an ordinary 4G63.
Somehow, I’m sure you want more than 400 HP. Well, let’s get to more aggressive mods.
Here are some changes and additions to the list above:

– a cold air intake
– a Mishimoto radiator
– a 3″ ETS intercooler and pipes
– an AMS intake manifold
– Kelford 272 cams
– adjustable cam gears
– valve springs and retainers
– an FP Green turbo + a manifold
– an Aeromotive fuel rail
– an Aeromotive fuel pressure regulator
– 1,000 cc fuel injectors
– an Aeromotive 340 lph
– a TiAL bypass valve
– an Evo turbo

You will have to install oil jets in your 4G64 cylinder block and remove the balance shafts, so they do not interfere in building a powerful engine.
This is enough for your 4G64 turbo to yield 500 HP at the crankshaft.
The next step is head porting + 1 mm oversized valves + valve springs + bronze valve guides.

4G64 2.1 destroker

You have an excellent cylinder block and sufficient displacement, but the 4G64/4G63 hybrid doesn’t like high revs. It’s good for daily commuting, but your goal is very high power. It is for this purpose that destorkers are made when the displacement is sacrificed using long rods and a short-stroke crankshaft. It gives a high ratio rod/stroke ratio and the ability to reach really high revs.
We have all the same setup — a 4G64 block with a 4G63 head, but the displacement is only 2.1 liters. Such 2.1’s are built to get the highest revs and to achieve the max HP.
Here is the list of upgrades for building your own destroke kit:

 – an Evo crank with the stroke of 88 mm
 – ACL bearings
 – 156 mm rods
 – the block should be bored out to fit 87 mm Wiseco pistons (or CP)

Installing oil jets into the block is mandatory.
Sometimes, 162 mm rods + forged pistons with reduced compression height are used. This will increase the R/S from 1.77 to 1.84.
If you have decided to build such a bottom-end, you will need to upgrade your new Evo head.
You have to buy and to do the following:

 – a Cometic head gasket
 – port and polish your head
 – bronze valve guides
 – oversized valves (+1 mm)
 – Supertech valve springs
 – solid lifters
 – Tomei 280 or GSC S3 cams, or even more “savage”
 – Tomei adjustable cam gears
 – ARP head studs
 – a 4″ intercooler + a piping kit
 – an AMS intake manifold
 – a 70 mm throttle body
 – an Aeromotive fuel rail
 – an Aeromotive fuel pressure regulator
 – 1600cc injectors
 – a Walbro 400 lph
 – a 3″ or even more exhaust system

For this engine, you can even choose an EFR 6466 and get next to 1,000 HP at the crank.
Alternatively, you can buy a Garrett GTX 3076 or an EFR 6262 turbo with a manifold and 272 cams, it will give you 600 HP at the crankshaft. And it will also be very quick.

The 2.2 stroker

This way is no different from what has been written above, but you will use a K1 94 mm crank. This will give you 2.2 liters of displacement (2.23 l) and still very high revs.

The 4G64 2.5 stroker

The last variant is increasing the displacement to 2.5 liters (2.42, to be exact). This requires a Brian Crower kit:

 – a 102 mm crank
 – 156 mm rods
 – forged pistons (CH = 28 mm).

The 4G64 2.6 stroker

This is probably the highest displacement you can get with this engine. However, the real displacement will be only 2.52 liters.
You will need the following components:

 – a 106 mm crank
 – 150 mm rods
 – 87 mm forged pistons (CH = 32 mm)
 – 156 mm rods
 – pistons with the compression height of 26 mm

If you bore out your block to 87.5 mm, the displacement will increase to 2.55 liters.