Mitsubishi 4G94

Mitsubishi 4G94 engine

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


Manufacturer Kyoto engine plant
Also called 4G9
Production 2000-2010
Cylinder block alloy Cast-iron
Configuration Inline-4
Valvetrain SOHC
4 valves per cylinder
4 valves per cylinder
Piston stroke, mm (inch) 95.8 (3.77)
Cylinder bore, mm (inch) 81.5 (3.21)
Compression ratio 9.5
Displacement 1999 cc (122 cu in)
Power output 91 kW (125 HP) at 5,200 rpm
106 kW (145 HP) at 5,700 rpm
Torque output 176 Nm (130 lb·ft) at 4,250 rpm
191 Nm (141 lb·ft) at 3,750 rpm
HP per liter 63
Fuel type Gasoline
Weight, kg (lbs) 150 (330)
Fuel consumption, L/100 km (mpg)

Mitsubishi Lancer
9.8 (24)
7.4 (32)

8.7 (27)
Turbocharger  Naturally aspirated
Oil consumption , L/1000 km
(qt. per miles)
up to 1.0
(1 qt. per 600 miles)
Recommended engine oil 5W-30
Engine oil capacity, L (qt.) 3.8 (4.0)
Oil change interval, km (miles) 5,000-10,000
Normal engine operating temperature, °C (F) 95
Engine lifespan, km (miles)
-Official information

200,000 – 250,000 (120,000 – 150,000)
Tuning, HP
-Max HP
-No life span loss


The engine is installed in Mitsubishi Lancer
Mitsubishi Galant
Mitsubishi Dion
Mitsubishi Pajero iO

Mitsubishi 4G94 engine reliability, problems and repair

The largest engine in the 4G9 family was 4G94, which had a displacement of 2.0 liters. The engineers took a cast-iron 4G93 cylinder block and did a good job with it. They increased the deck height to 231.3 mm and increased the cylinder bore from 81 mm to 81.5 mm. Into this block, they installed a 95.8 mm long-stroke crankshaft, 152.9 mm conrods, and 81.5 mm pistons with a compression height of 30.4 mm. All this yielded 2 liters of displacement.
On top, they installed a SOHC head with one camshaft and 16 valves. This camshaft has a duration of 248/240 degrees. The size of intake valves is 32 mm, of exhaust valves — 29 mm. A multi-point fuel injection system was used for this head.
There was yet another version with a DOHC head and two camshafts. Their duration was 246/250 degrees. They used a direct fuel injection system for 4G94 GDI.
Valve adjustment is not required here – the 4G94 engine uses hydraulic lifters.
All these 4G94’s use a timing belt, but it should be replaced after every 60,000 miles (90,000 km). If it breaks, the valves will bend.
The injector size is 240 cc and the size of the stock throttle body is 52 mm.

Mitsubishi 4G94 engine problems and malfunctions

It is the same 4G93, but slightly larger, which means their problems are no different. Learn about them HERE.

Engine number location

4G94 number location

Mitsubishi 4G94 engine tuning


It is a rather dubious way, you won’t get a significant power boost. But if you are a stubborn man, buy a cold air intake system, an Evo throttle body, a ported 4G93 intake manifold, high compression pistons (CR > 10.5) and aftermarket rods. Then, send your SOHC head for port and polish, buy a Stage 2 camshaft, and select an ECU to configure all these engine mods. Know what you will get in the end? Almost nothing! Your engine will add about 20 – 30 HP, but it will take a lot of your money and time. For instance, forget all this and let’s see what really gives power!


I’m sure you know about the existence of the great 4G92 MIVEC head, and you will definitely want to install it on your 2.0-liter engine block. For a successful SOHC to DOHC MIVEC conversion, you will need to buy a 4G92 MIVEC head with the entire intake and exhaust systems. You will also have to buy 4G92 pistons, ACL main and rod bearings, a 4G93E oil pump, a MIVEC ignition and fuel systems, a head gasket, head bolts, a 7M-GTE timing belt, and a 4G92 harness. This will immediately give you 200 HP. Need more? Port and polish your new MIVEC head. And add some performance parts, such as a cold air intake system, an EVO throttle valve, a 4-1 header, and a 2.25-inch exhaust system. You do not have to use high compression pistons, but you can do it. You will need a standalone ECU; this may be a Haltech P1000 or something else. Configure those upgrades, and you will get more than 220 HP.
You can try installing JUN type 1 camshafts to add a little more power.

4G94 Turbo MIVEC

You can choose the forced induction way and get the same 200 – 250 horsepower, but using a Mitsubishi Evolution TD05H-16G turbocharger and low boost pressure, because stock internals of your 4G94 are not too strong. They should withstand the boost pressure of approximately 0.5 – 0.6 bar. This will give you about 200 HP.
It is easy to understand that you want more, which means that you need to make a really powerful engine. To do this, you should replace stock pistons and rods, they are the weak point here. It is better to use K1 rods and forged Wiseco pistons or CP pistons (whatever you like the best) with the compression ratio of approximately 9:1. Also buy ACL bearings, ARP head studs, and an oil cooler. These forged internals will let you get much more than 200 HP. The Evo turbocharger is a good choice, but to assemble a full-fledged turbo kit, you need to buy some more performance parts: a turbo manifold for your Evo turbocharger, a large intercooler and pipes, an Evo throttle body, NGK spark plugs, a Walbro 255 fuel pump, an AEM fuel rail, an Aeromotive fuel pressure regulator, 630 cc fuel injectors, a 272 cam, valve springs, a 2.5-inch exhaust system, a boost controller and a standalone ECU (e.g., Haltech or similar).
In the end, you will get 300 HP and even more. You may also use a 4G93E DOHC head instead of your SOHC head.