Four-cylinder engines are extremely common across the car industry. You’ll find 4-cylinder engines under the hood of hybrids like the Toyota Prius, pickup trucks like the Chevrolet Silverado 1500, and even some performance cars like the Ford Mustang. When you’re on your daily commute, there’s a good chance that the majority of cars you see on any given day use a 4-cylinder engine.
So, what is a 4-cylinder engine and what does it do? Let’s take a closer look at the engineering that makes them work and whether a car, truck, or SUV with a 4-cylinder engine is right for you.
What Is a Cylinder?
The cylinder is what generates power in an internal combustion engine. A cylinder consists of a piston, intake and exhaust valves, a spark plug, and — in direct-injection engines — a fuel injector. Generally speaking, more cylinders mean more horsepower, and fewer cylinders mean better fuel economy. Simple, right?
Four is widely considered the optimal number of cylinders for an average car or SUV that needs a good balance of power and efficiency.
Traditionally, a 6-cylinder engine has been considered a happy medium between an efficient 4-cylinder and a powerful 8-cylinder engine. However, 4-cylinder engines have gotten more powerful over the years thanks to tricks like variable valve timing and turbocharging, making 6-cylinder engines less popular than they used to be, especially in sedans.
How Does a 4-Cylinder Engine Work?
A 4-cylinder engine works like any other internal combustion engine. A mixture of air and gas enters the cylinders through the intake valves. The pistons inside the cylinders compress this air/gas mixture, and the spark plugs ignite it, creating combustion. The piston goes back down, and exhaust escapes the cylinders through the exhaust valves.
The pistons connect to the crankshaft with connecting rods. These tiny explosions make the pistons move up and down, powering a crankshaft. The engine then delivers power to the wheels of the car through the transmission.
Four-cylinder engines have a wide range of benefits, including good fuel economy and low maintenance costs. Here are some of the most significant advantages of 4-cylinder engines:
- Good fuel economy — 4-cylinder engines typically don’t burn a lot of gas. It’s not hard to find a small car with a 4-cylinder engine with an EPA fuel economy rating of over 40 mpg on the highway like the Kia Rio and Hyundai Accent.
- Smaller carbon footprint — Since 4-cylinder engines don’t burn a lot of gas, they’re more environmentally friendly than most engines with six or eight cylinders. Many hybrids use a 4-cylinder engine, including the Toyota Prius and Hyundai Ioniq.
- Affordable — 4-cylinder engines are often more affordable than bigger engines. For example, the cheapest variants of the Ford Mustang and Chevrolet Camaro use 4-cylinder engines.
- Low maintenance costs — 4-cylinder engines are typically pretty cheap to maintain. For example, when it’s time to replace the spark plugs, you only need four of them rather than six or eight in a bigger engine.
Cars with a 4-Cylinder Engine
Vehicles with a 4-cylinder engine range from sports cars to commercial vans to pickup trucks, but most often, you’ll find them in smaller cars and SUVs. Here are just a few of the many cars and SUVs available today with a 4-cylinder engine under the hood:
Is It Better Than a 6-Cylinder Engine?
Whether a 4-cylinder engine is better than a 6-cylinder engine is debatable. The usual trade-off is better fuel economy with a 4-cylinder and more power with a 6-cylinder, which is most commonly in a V6 configuration. If you’re willing to sacrifice some efficiency for better performance, a 6-cylinder engine might be better for you.
With innovations like turbocharging, direct injection, and the novel engineering of variable compression in some cars like the Nissan Altima, you can get close to getting the efficiency of a 4-cylinder with the performance of a 6-cylinder with little compromise.
Another thing to keep in mind is that 6-cylinder engines are typically better for towing than a 4-cylinder. For example, the 4-cylinder Volkswagen Atlas has a maximum towing capacity of only 2,000 pounds, but the same SUV with the available V6 engine tows up to 5,000 pounds.