Mitsubishi 4G92

Mitsubishi 4G92 engine


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

Specs

Manufacturer Kyoto engine plant
Also called 4G9
Production 1991-2005
Cylinder block alloy Cast-iron
Configuration Inline-4
Valvetrain SOHC
4 valves per cylinder
DOHC
4 valves per cylinder
Piston stroke, mm (inch) 77.5 (3.05)
Cylinder bore, mm (inch) 81 (3.19)
Compression ratio 10.0
11.0
Displacement 1597 cc (97.5 cu in)
Power output 69 kW (94 HP) at 5,500 rpm
75 kW (103 HP) at 6,000 rpm
83 kW (113 HP) at 6,000 rpm
108 kW (147 HP) at 7,000 rpm
125 kW (170 HP) at 7,500 rpm
Torque output 135 Nm (100 lb·ft) at 4,000 rpm
141 Nm (104 lb·ft) at 4,500 rpm
137 Nm (101 lb·ft) at 5,000 rpm
149 Nm (110 lb·ft) at 4,500 rpm
167 Nm (123 lb·ft) at 7,000 rpm
Redline 7,800 (MIVEC)
8,200 (MIVEC RS)
HP per liter 59
65
71
92
106
Fuel type Gasoline
Weight, kg (lbs) 145 (320)
Fuel consumption, L/100 km (mpg)
-City

-Highway
-Combined
Mitsubishi Mirage
8.6 (27)
5.6 (42)

7.7 (31)
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
5W-40
5W-50
10W-30
10W-40
10W-50
15W-40
15W-50
20W-40
20W-50
Engine oil capacity, L (qt.) 3.8 (4.0)
Oil change interval, km (miles) 5,000-10,000
(3,000-6,000)
Normal engine operating temperature, °C (F) 90-95
Engine lifespan, km (miles)
-Official information
-Real


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

300+

The engine is installed in Mitsubishi Carisma
Mitsubishi Colt
Mitsubishi Mirage
Mitsubishi Lancer
Mitsubishi Dingo
Mitsubishi Libero
Proton Wira

Mitsubishi 4G92 engine reliability, problems and repair

We continue to look at the Mitsubishi 4G9 family, and I suggest taking a look at the 4G92 engine and the difference between 4G92 and 4G93. For instance, in 1991, engineers created a 1.6-liter engine based on 4G93. They made the cylinder block lower, its deck height is now 188.75, and installed a new crankshaft with a piston stroke of 77.5 mm inside the block. The conrod length is now 120 mm. The cylinder bore has not changed and is still 81 mm. The compression height of the pistons is 30 mm. As a result, we have 1.6 liters of displacement.
You can meet a 4G92 with one camshaft — a SOHC head, or with two camshafts — a DOHC head. Both of these versions have 16 valves.
4G92 SOHC is a version for saving fuel, it only has 94 HP. The camshaft is 254/246 degrees. For the domestic Japanese market, 113 HP 4G92 SOHC were released because of the higher cam.
The compression ratio of these engines is 10:1, their fuel injector size is 190 cc, and the size of the throttle body is only 48 mm. The 4G92 DOHC engines are more interesting, they are really “savage” and fast. In these engines, the compression ratio has been increased to 11:1.
The first variant is 4G92 DOHC non-MIVEC (1991 – 1993). It is from this engine that the entire 4G92 series started. It boasts 147 HP at 7,000 rpm and the torque of 149 Nm at 4,500 rpm. It was a competitor to the famous Honda B16A.
In 1992, a more aggressive 4G92 DOHC MIVEC appeared. It got a variable valve timing system and duration 228/232 deg, lift 7.58/8.2 mm camshafts. At high speeds, the MIVEC system switched to large cams, their duration is 283/300 deg, and the lift is 10.41/9.83 mm.
The size of the fuel injectors was increased to 275 cc, and the throttle body size was 60 mm
The power of this engine reached 170 HP at 7,500 rpm, the torque was 167 Nm at 7,000 rpm.
There were three versions:
– 4G92 MIVEC Silvertop with the rev limiter at 7,800 rpm.
– 4G92 MIVEC-MD, where the engine ran as an 8V at lower rpm and saved fuel.
– 4G92 MIVEC RS Blacktop with a different intake manifold, camshafts, and valves, a lightweight flywheel, and a new exhaust system. Another ECU was also used here, and the redline was raised to 8,200 rpm. The power grew to 175 HP.

It was a worthy competitor to B16A5 or B16A SiR 2. You can meet the Mitsubishi Lancer MR of those years with these engines.
Most popular 4G92 SOHC has no hydraulic lifters, and valve adjustment is needed after about every 30,000 miles (50,000 km). Here is the valve clearance for a hot engine: IN 0.2 mm, EX 0.3 mm; valve clearance for a cold engine: IN 0.1 mm, EX 0.2 mm. It uses a timing belt, you have to replace it after every 60,000 miles (90,000 km), otherwise, it will break and the valves will bend.

Here are other engines of the 4G9 series that are very similar to 4G92: 1.8 liter 4G93, 4G94 2.0 liter, and the small 4G91, with the displacement of only 1.5 liters.

Mitsubishi 4G92 engine problems and malfunctions

1. Knocks in the engine. Check the hydraulic tappets, if necessary, replace them. Usually, the problem is in these components.
2. Increased oil consumption. Do not be surprised, your car is quite old. In this case, an overhaul is required.
3. Idle problem. This happens due to a faulty idle air control valve (IAC valve), MAF-sensor, or due to the dirty throttle body. Check all of these, you will probably find the reason.
Summing up, it is a pretty good engine with high reliability that can run more than 200,000 miles (300,000 km).

Engine number location

4G93 number location

Mitsubishi 4G92 engine tuning

Naturally aspirated

First, I want to tell owners of 4G92 SOHC, listen, guys, your head is good for nothing, and you just waste your time working with it. You should convert you 4G92 SOHC to DOHC or just forget about high power.
To make your SOHC engine show 130 HP, you will have to find a high cam, buy a cold air intake, a 4G63 throttle body, a 4-2-1 header, a performance exhaust system, and for all these upgrades to yield a result, you have to configure the ECU. Do not waste your time on this.
To install a 4G92 MIVEC head, you will need not only a head with a gasket and bolts, you will also need an intake system, an ignition system, a timing belt and everything associated with it, a fuel rail, a water pump, a 4G93 oil pump, a 4G93 oil pan, a front crankshaft seal, a MAP sensor, an IAT-sensor, and a good exhaust system.
Let’s move on to the really aggressive 4G92. Is your stock high-rev MIVEC really not enough for you?? Okay, let’s talk about how to add some power.
You can start with the simple stage 1: a cold air intake system, a 4-1 header, a performance exhaust system, and ECU tuning. Let’s be honest, it will not give any practical result, but the sound will be louder, it’s true.
Now in earnest. We will install individual throttle bodies from AE111, but they need to be slightly adapted to your MIVEC engine. You can use a 70mm throttle body if you want. The exhaust system will consist of a 4-1 header and a 2.5-inch straight exhaust pipe. But this is only the beginning, this will not be enough. We will not increase the displacement, we will buy H-Beam rods, ARP rod bolts, ACL rod bearings, and 81mm high compression pistons. These upgrades will improve reliability at high rpm, and increase the compression ratio to 12.5, or even 13.
You should port and polish the head, buy Jun type 2 cams, adjustable cam gears, a lightened flywheel, and an Evo fuel pump. All this will be controlled by a Haltech E6X, or something else that you like more. All this will give a lot of power with the use of sports fuel.

4G92 MIVEC 1.8

Yes, it is possible, but you will need a 4G93 cylinder block. It will be something like a stroker kit, but even better. After you reach the maximum power for 1.6 liters of displacement, you will have no choice, you will have to get 1.8 liters. Leave your upgraded head and replace your small cylinder block to the 4G93. You should also add large 390 cc 4G93T fuel injectors, this will be enough. In the end, you will get 200 HP at the crankshaft, or even a little more.
If this is not enough, you can bore out your 4G93 cylinder block to 83 mm; this is the maximum size. It will give you 1.93 liters of displacement.

Turbo

It is best to use a 4G92 MIVEC head + a 4G93 block, these additional .2 liters will be needed because we want a fast car, which means we need to use the Evo TD05 turbocharger.
You can leave stock internals, but the pistons still should be replaced to make the compression ratio about 9:1. These stock rods can withstand over 300 HP.
For a turbo project, a 4G93 block + a MIVEC 4G92 head is the best solution. Our goal is getting 300+ HP, and the TD05H-16G turbocharger can do it. We need to make an oil feed and an oil drain line for the turbocharger. Of the performance parts, you will need a turbo manifold, an Evo oil cooler, an Evo intercooler, an intake piping, a 4G63T throttle body, an Evo fuel pump, a fuel rail, an adjustable fuel pressure regulator, 630 cc or more fuel injectors. The exhaust system should have a diameter of approximately 2.5″.
Into the cylinder block, we will install 4G93T pistons and 4G93T conrods, as well as oil squirters. You can use forged pistons and rods; this will let you go even further. To configure all that, you can use Megasquirt or something similar.
These upgrades will give you 300-350 HP, but you need so many parts from Evolution that it’s easier to buy a Mitsubishi Evolution, it’s the same.