Mitsubishi 4G93: Everything You Need To Know

4G93 engine is a member of the Mitsubishi 4G9 series along with several other engines: 2.0 L 4G94, 1.6 L 4G92, and the small 1.5 L 4G91. 4G9 series is a straight-4 engine that both use 16-valve single and double overhead camshafts.

Some variants feature MIVEC variable valve timing, and it was the first GDI (Gasoline Direct Injection) engine since its introduction in August 1996.

4G9s first appeared in the 4G91 Mitubishi Lancer and Mirage. They are still roaming the streets with ease and pride.

So today, we will talk about the 4G93 engine’s design, variants, power, torque, and overall impact on the automotive industry.

Let’s get right to it.

Engine Specifications and Design

• Production Run: 1991 – 2010
• Cylinder Head Material: Aluminum
• Cylinder Block Material: Cast-iron
• Configuration:Inline-4
• Bore: 81 mm
• Stroke: 89 mm
• Valvetrain: SOHC and DOHC 4 Valves per Cylinder
• Displacement: 1.8 L
• Compression Ratio: 8.5, 9.1, 9.5, 10.0, 10.5, 12.0
• Weight: 330 lbs.
• Max HP: 215 HP
• Max Torque: 209 lb-ft

Mitsubishi 4G93 are inline-four engines with a 1.8 Liter displacement that are available in both SOHC, DOHC versions and turbocharged variants. The first GDI models were successful despite their infamous reputation as heavy polluters.

That somehow restricted its reach, selling only through Japanese markets. Still, it was able to produce more than a million units. Since the European market has its own uniform and standard emission requirements, the cleaner version was later sold there but has less power and among the first of the many modern GDI engines.

This engine is extremely reliable and has a good fuel economy.

Under the hood, you have a cylinder block that is made of cast iron, with a deck height of 208.75 mm, 133.35 mm rod length, 30.8 mm compression height, 81-mm cylinder bore, and a piston stroke of 89.8 mm.

The cylinder heads vary depending on the 4G93 modification of your choice. But the first and simplest is the SOHC 16-Valve Head which is installed with either the MPI (Multi-Point Injection) or carburetor injection.

This engine can produce 117 HP for the MPI and 101 HP for the carburetor, with a compression ratio of 9.5 and 122 lb-ft of torque.

The second variant is the DOHC 16-valve head, which has a higher compression ratio of 10.5. It can deliver 138 hp at 6,500 and 123 lb-ft torque at 5,500 RPM. This engine could be either with MPI or with the direct injection system GDI.

The third variant is the 4G93T, a turbocharged version of the 4G93 with a DOHC 16-valve GDI head. It has a compression ratio of 10.; a small MHI TF035HM-12T-5 turbocharger. It can produce 162 HP at 5,500 RPM and 162 lb-ft of torque at 3,500 RPM.

In mid-1996, Mitsubishi released a gasoline direct injection (GDI) version of the 4G93. This GDI model produced over a million units in the Japanese market, which were later sold in European markets.

But the most powerful and aggressive engines are the ones with the DOHC MPI 16-valve head. More commonly known as the first-generation 4G93T. Even though it has a lower compression of 8.5, it can produce 194 HP at 6,000 RPM and 200 lb-ft of torque at 3,000 RPM with the help of the TD04L-13-G-5 turbocharger.

Following that, the compression ratio was increased, so do the power outputs. Power was increased to 205 HP and 215 HP much later on. This engine model is known as the 4G93 second-generation, and it uses 390 cc fuel injectors, a turbocharger, and has a compression ratio of 9.1. Such engines appear in Lancer GSR.

Some Applications of the 4G93 Engine:

• Mitsubishi Space Wagon
• Mitsubishi Space Star
• Mitsubishi Carisma
• Mitsubishi Lancer
• Mitsubishi Mirage
• Mitsubishi FTO
• Proton Wira
• Proton Satria
• Proton Putra
• Mitsubishi Colt GTI
• Mitsubishi Galant 1996
• Mitsubishi Pajero, Shogun Pinin, Pajero Pinin, Monter iO, TR4
• Brilliance BC3
• Brilliance BS6
• Brilliance BS4
• Volvo S40
• Volvo V40

Engine Upgrades, Tuning, and Modification

There are two options for 4G93 engine tuning. One is the MIVEC, and the other is the common one, Turbo.

MIVEC means supplementing the needs of your engine depending on its deficits. In order to build a 4G93 with MIVEC, you need to buy a MIVEC head, head gasket, stock rods, 4G92 pistons, 4G92 intake manifold, 4G94 timing belt, 390 cc fuel injectors (used in Lancer GSRs), and a 4G92 ECU.

Install the head and other components. It will add at least 180 HP at the flywheel. But suppose you want to up to 200 HP.

In that case, you will need naturally-aspirated mods like a cold air intake system, 63 mm throttle body (or ITB), 272 cams, adjustable cam pulley, heavy-duty valve springs, 4-2-1, header, 2.5-inch exhaust system, lighter flywheel, 360 cc fuel injectors, fuel regulator, a performance intake system, and an Haltech ECU. Top it off with head porting and polish.

Turbo

Building turbocharged 4G93 is as easy and fast as its sounds. First, you will need to buy a 4G93T TD04L turbocharger turbo kit, or If you want a bigger turbo, and that means an enormous boost on your power output.

You can buy the EVO turbocharger TD05H-16G with a large intercooler, an EVO throttle body, Walbro 255 fuel pump, 630 cc fuel injectors, turbo manifold, fuel rail, 2-inch piping, and a 2.5-inch performance exhaust system.

Also, install oil squirters into the naturally aspirated cylinder block and use forged internals, or you can use the 4G93T pistons and rods. This can easily give you 300 Horsepower.

The 4G93T GDI version, unfortunately, has a low boost pressure which amounts to smaller power output. You can do an upgrade to at least ceiling it to 0.8 bar by buying an EVO intercooler, exhaust system, ECU tuning, Evo fuel injectors, Evo fuel pump, Evo oil cooler, and an Evo throttle body.

High performance on display by the Evo components in a 4G93 body.

Problems Surrounding 4G93 Engines:

Though 4G93s are highly reliable engines, we can’t avoid some circumstances that might come down the line especially considering all the moving parts inside the block. Some issues are more common than the others, so here are some problems that might occur in your 4G93 engine:

First is the high oil consumption. High oil consumption is a result of aging and loose internal components. Problems that involve oil consumption escalates badly due to the significant role of the oil for the engine; it helps cool down the pistons and lubricates it and keeps the overall condition of the car good.

But the main suspect is the engine’s age, adding that with poor maintenance and insufficient oil quality will hurt the machine for sure. You might need an overhaul by disassembling the engine and assess it or replace the piston rings and valve stem seals. But most of the time, it is the former.

Next is the knocking sound in the engine. Again, just like we mentioned above, poor-quality oils can jeopardize the overall condition of the machine. And one of those detrimental results is the knocking sound that’s coming straight from the bay, particularly from the hydraulic lifters.

Hydraulic lifters are used instead of valves in 4G93s. This can be solved by replacing the hydraulic lifters. Countries with poor engine oil options are more prone to this problem.

The third is bad idling. This is more prevalent in GDI engines, for this engine producer more output than MPI ones. And the reason behind this issue is a clogged high-pressure fuel pump, primarily, and a dirty throttle body.

Both are essential elements in delivering fuel services in the engine. You need to clean those two and also check the idle air control valve, and it might be there. Replace if needed.

4G93 also has an issue with its EGR valve, especially the GDIs.

It can be caused by a clog in the intake manifold, which needs to be cleaned regularly. And one more thing, all the 4G93 heads use a timing belt instead of the chain, so replacing it every 60,000 miles is a good practice to avoid breakage and to avoid further problems.

Summary

4G93 engines are popular engines since they were produced 20 years ago. It has placed and cemented itself as one of the well-known powerplants and continues to do so. It has different variants and can be tuned depending on the power output of your liking.

Though it has some minor problems that you may encounter, proper maintenance and care of the engine can serve you more than you can think of. Just use high-quality proponents to maintain the proper condition of the engine.

I hope that this information we discussed today helped you understand the Mistubishi 4G93 engine even more. Whether you are planning to buy one or already own one, may this be a helpful guide for you.