What is the difference between 3-cylinder and 4-cylinder engines?

[AlinaMarie]

The differences between 3-cylinder and 4-cylinder engines: 1. Manufacturing structure: The 3-cylinder turbocharged engine has a simpler manufacturing structure, is smaller in size than a 4-cylinder engine, and is lighter in weight. 2. Acceleration: The 4-cylinder turbocharged engine performs better in terms of starting and acceleration, and its stability is superior to that of the 3-cylinder engine. 3. Operation state: The 3-cylinder engine operates in an unbalanced state, making it more prone to vibration compared to the 4-cylinder engine. 4. Noise: The 3-cylinder engine is louder than the 4-cylinder engine, and despite the use of balance shaft technology, the issue remains unresolved. 5. Displacement: 4-cylinder engines are typically used in cars with a displacement of 1.3L or more, offering greater displacement and naturally more horsepower compared to 3-cylinder engines.

[Miller]

I've driven over a dozen cars, and the vibration difference between 3-cylinder and 4-cylinder engines across various models is significant. With fewer cylinders, 3-cylinder engines exhibit particularly noticeable vibrations during startup and idling—steering wheels and seats subtly tremble, making driving feel less smooth, especially at red lights or low speeds. In contrast, 4-cylinder engines are far better balanced, running so smoothly that vibrations are nearly imperceptible inside the cabin, enhancing comfort on long drives. This stems from their internal design: 4-cylinder engines evenly distribute ignition sequences to cancel out vibrations, whereas 3-cylinder engines rely on additional mechanical compensations with limited effectiveness. In daily use, 3-cylinder vibrations compromise comfort, such as causing fatigue in urban traffic jams; 4-cylinders excel during highway cruising or long trips. While modern models have improved, if prioritizing a comfortable driving experience, I still lean toward 4-cylinder options when choosing a car.

[SanEverly]

Having focused on engine performance for years, the key difference between 3-cylinder and 4-cylinder engines lies in power delivery continuity. A 4-cylinder engine operates with four cylinders working in sequence, providing smooth and linear acceleration without sudden jerks when flooring the throttle, and delivers consistent power during high-speed overtaking. In contrast, a 3-cylinder engine exhibits uneven output, often with irregular vibrations, and shows noticeable power deficiency or fatigue at high RPMs. This impacts real-world driving scenarios—for instance, a 4-cylinder proves more reliable when climbing hills or navigating mountain roads. However, 3-cylinder engines are lighter and more compact, offering quicker urban responsiveness, such as sharper overtaking agility. Turbocharging technology, like in the BMW 1 Series 3-cylinder variant, significantly enhances performance. Overall, prioritize a 4-cylinder for stable power delivery, while a 3-cylinder suits those valuing compactness and agility.

[Pauline]

For commuting enthusiasts, fuel efficiency is paramount. The 3-cylinder engine has a simpler structure with fewer parts, resulting in lower friction losses and typically better fuel economy than a 4-cylinder over the same distance, allowing you to go farther on a single tank. The 4-cylinder engine averages higher fuel consumption but offers better comfort. In daily driving, the 3-cylinder's cost-saving advantage is evident, making it ideal for budget-friendly compact cars like the Ford Focus 3-cylinder variant. The 4-cylinder is better suited for long-distance travel or heavy-load scenarios. Maintenance costs also differ—3-cylinder engines, being lighter, may be cheaper to repair, while 4-cylinders tend to be more wear-resistant. Overall, for an economical choice, the 3-cylinder takes priority.