Mitsubishi 4G15 Engine: Specs, Performance, and Tuning Guide

The Mitsubishi 4G15 engine is a reliable and versatile powerplant that has powered various models within the Mitsubishi lineup. Known for its durability and potential for enhancement, this compact, inline-four engine has earned respect among enthusiasts. As emissions standards tighten and fuel efficiency becomes more important, understanding engines like the 4G15 remains relevant.

Exploring the specifications, performance characteristics, and tuning options of the 4G15 highlights why it continues to appeal to both everyday drivers and car modifiers.

Engine Specifications

The Mitsubishi 4G15 engine, part of the 4G1 family, is a 1.5-liter inline-four engine that has been a mainstay in Mitsubishi’s lineup. Its single overhead camshaft (SOHC) design makes it simple and easy to maintain. With a bore and stroke of 75.5 mm and 82 mm, respectively, the engine strikes a balance between efficiency and performance. Its compact size and lightweight construction make it suitable for a variety of vehicles, offering a practical mix of power and economy.

Fuel delivery is managed by a multi-point fuel injection system, ensuring precise fuel atomization and distribution. This system enhances responsiveness and fuel efficiency. The engine’s compression ratio, typically around 9.2:1, allows it to run efficiently on regular unleaded gasoline. Its cast iron block and aluminum cylinder head provide a sturdy yet lightweight structure.

The 4G15 engine produces approximately 92 horsepower and 93 lb-ft of torque, depending on the model and market. While modest, this output is adequate for daily driving. A balance shaft system reduces vibrations, improving driving comfort, especially on longer trips.

Performance Characteristics

The 4G15 engine offers a balanced performance that suits urban commuting and casual drives. While it isn’t the most powerful engine in its class, it emphasizes steady performance and fuel economy. Its consistent power delivery supports smooth acceleration and a comfortable driving experience.

One of the engine’s strengths is its responsiveness. The multi-point fuel injection system ensures even fuel distribution, resulting in linear power delivery. This feature enhances drivability, especially in city environments with frequent stops and starts. The system’s precision also improves throttle response, which is useful for maneuvering through traffic or merging onto highways.

The engine’s lightweight construction contributes to both fuel efficiency and handling. Vehicles with the 4G15 feel nimble, making them easier to drive in tight spaces or on winding roads. This agility, combined with smooth power delivery, ensures an engaging driving experience despite the engine’s modest output.

Common Modifications

Enthusiasts often modify the 4G15 engine to improve performance and personalize their vehicles. Upgrading the intake and exhaust systems is a common starting point. Replacing the factory air filter with a high-performance version improves airflow, potentially increasing power. Pairing this with an aftermarket exhaust system can reduce back pressure and enhance exhaust flow.

ECU tuning is another popular modification. Adjusting fuel maps, ignition timing, and other parameters can optimize performance for specific goals, such as increased power or improved fuel economy. Tuning solutions from companies like Hondata or ECUtek allow for customization based on individual preferences.

Suspension upgrades can also enhance the performance of vehicles equipped with the 4G15. Installing components like coilovers or sway bars improves handling and cornering. Brands like Tein and Eibach offer options that cater to different driving styles, making the vehicle more dynamic and enjoyable to drive.

Vehicle Compatibility

The Mitsubishi 4G15 engine has been used in a variety of vehicles, demonstrating its adaptability across different platforms. From compact sedans to hatchbacks, it has powered models like the Mitsubishi Mirage and Lancer, appealing to drivers who value reliability and efficiency.

In older models, the 4G15 was used in vehicles such as the Mitsubishi Colt and Proton Saga, where it served as a dependable engine. Its widespread use across different markets highlights its versatility and the confidence manufacturers have in its capabilities. The engine’s adaptability has also made it popular in international markets.

Tuning Potential

The tuning potential of the 4G15 engine attracts car enthusiasts eager to enhance performance. While modest in stock form, the engine offers various options for those looking to increase power and refine its capabilities. Turbocharging is a popular modification, providing a significant boost in horsepower and torque. Kits from companies like Garrett or BorgWarner cater to different performance goals.

Supporting modifications are necessary for turbocharging. Larger injectors, a high-flow fuel pump, and an upgraded intercooler help manage the increased fuel and air demands, ensuring reliability and efficiency. Together, these upgrades can transform the 4G15 into a more powerful engine for street or track use.

For those who prefer naturally aspirated tuning, options like high-compression pistons, performance camshafts, and a ported cylinder head can improve engine breathing and efficiency. These modifications enhance throttle response and allow the engine to rev higher, creating a more engaging driving experience. Custom tuning solutions, such as those from MegaSquirt, can optimize these changes for maximum performance tailored to the driver’s preferences.