Car engines are kept in place under the hood of the vehicle and they typically resemble a massive, perplexing mix of cables, tubes, and metal. Because of this, all the energy is converted into a mechanical form, enabling your car to run. There are many various types of car engines, each with unique features serving the same function. If you own a car or are considering purchasing one, you must familiarise yourself with the various car engine types.

So, if you are looking to buy a new car or already have a car, you might prefer to look into specific details rather than just their classification.

1. Car Engines Based on Layout

Modern internal combustion engines frequently share comparable crucial components. As a result, you might observe things like spark plugs, chambers, pistons, etc. Such parts, however, would be situated differently because they are distributed across the layout in various locations.

Depending on the purpose, these car engine layouts typically vary. For example, smaller cars will demand a more compact engine. Nevertheless, a few of the different types include – 

• Straight Engine 

In a straight engine, all of the cylinders are arranged in a linear configuration. Additionally, these engines also run parallel to the length of the car. In simple words, these engines move from the front to the back of the engine bay, and the engine can have more cylinders in this arrangement. This setup is typically used in more potent cars such as sedans, but this is not to be confused with inline engines. 

• Flat Engine 

Flat engines are manufactured as flat as they can be. This is because its cylinders are positioned flat in both directions, and users occasionally refer to it as a boxer engine as well. Additionally, the cylinders on both sides will be placed in such a way that the pistons face outward. It maintains a car's low centre of gravity, and as a result, it is significantly simpler to drive.

• Inline Engine

In this arrangement, cylinders are arranged in a row. It is, therefore, often compared to a straight engine. But, the positioning of the two of the cylinders are different. It doesn't travel from front to back, yet it is straight and parallel to the car. It, therefore, moves from the left side of the engine bay to the right. 

Also, some users may refer to the cylinders as being side by side. Such a design is appropriate for engines that are intended to be compact, so it creates more room around the engine. Further, being compact, it consequently makes room for elements like the cooling system and the vehicle battery. 

• V Engine

A V-type configuration is preferable to an inline configuration as the number of cylinders rises. Essentially, this refers to two banks of in-line cylinders that are attached at an angle to form a V and hence, the name. Due to their lower length, these are significantly smaller than inline types. However, these are also slightly wider. 

In general, cars use a V-type layout to mount their 6, 8, 10, or 12-cylinder engines. The intrinsic quality of such a setup is that the V-type engines are exceptionally balanced and smooth. Nowadays, if there are more than 4 cylinders in an automobile, a V-type configuration is most likely to be used.

2. Car Engines Based on Configuration

An engine's power production and fuel efficiency are primarily influenced by the number of cylinders. Nevertheless, a few of the classifications include – 

• Twin Cylinders

The twin cylinders are typical for four-wheeled vehicles, and it’s more like a basic engine. When compared with two-wheelers, scooters and motorcycles use the one-engine variant, and when it comes to cars, twin cylinders are like the fundamental types. Since it’s the most basic, you’ll find these engines with meagre power output.

• Three Cylinders

Another variety of engines that can be seen in compact vehicles is the one with three-cylinders. Some manufacturers also add a turbocharged version as an addition to a twin-cylinder engine.

Ford Focus is an ideal example of a vehicle equipped with this engine. It produces more power than a typical three-cylinder engine and also provides good fuel efficiency.

• Four Cylinders

One of the most popular cylinder arrangements on the market today is the four-cylinder engine. Most importantly, these four cylinders often come in an inline style.

A four-cylinder engine also occupies less space with this type of structure, so you'll find this kind of engine in affordable car models. Additionally, these vehicles find a balance between size and performance for both regular and irregular use, so it is a popular choice among manufacturers. 

• Five Cylinders

This kind of engine is somewhat infrequent and can rarely be found in a car. However, it is mostly recognised for the distinctive sound that it makes when running. For instance, some individuals say it sounds like it is warbling. Its eccentric sound results from the odd firing order of the five cylinders.

Due to its rarity, this kind of engine may only be found in a few brands and models. Audi and Volvo are two examples of companies that produce such automobiles.

• Six Cylinders

A six-cylinder engine has a distinctive sound, just like a five-cylinder engine. But, it produces a more high-pitched roar, which is comparable to that of a race car.

Most importantly, only high-end vehicles typically have this kind of engine. Additionally, all six cylinders could be arranged in a straight line, and it's also present in V Engines.

• Eight Cylinders and More

When producing a lot of power with a smooth distribution is the aim, V-8 engines are among the most popular engine designs in the entire automobile industry. This is why having eight or more cylinders would result in better performance. Thus, racing automobiles and supercars typically have eight or more cylinders.

3. Car Engines Based on Fuel Used

If fuel is concerned, the different types of car engines are –

• Diesel Engine

Diesel oil is used to power these kinds of engines. In a diesel engine, the suction stroke solely draws air into the cylinder, which is then compacted to high pressure with a compression ratio of up to 22:1. Consequently, its temperature rises by around 1,000°F.

At the finish of the compression stroke, the diesel oil is pumped via an injector, which ignites and fires due to the hot compressed air. There is no need for a separate ignition system in this type of engine. Additionally, during the power stroke, the burned gases expand and force the piston downward. Then, during the exhaust stroke, the gases are forced out.

• Petrol Engine

A petrol engine runs only on petrol which is a hydrocarbon. A hydrocarbon composed of compounds containing hydrogen and carbon is known as petrol or gasoline. During the piston's suction stroke, an air-petrol mixture is drawn into the cylinder, and the carburettor provides the proper air-fuel mixture.

Additionally, compression occurs during the compression stroke, ignition occurs during the power stroke, and exhaust occurs during the exhaust stroke. Then, the mixture is ignited by a spark produced by a spark plug that is installed at the top of the cylinder.

• Gas Turbine

Essentially, a gas turbine has two sections: a gasifier part and a power section. Gas turbines can run on oil, kerosene, or gasoline as fuel. Burning fuel in a burner in the gasifier portion produces gas, which is then delivered to the power section to spin the power turbine. The vehicle wheels are then turned by the power turbine using a set of gears.

Furthermore, the compressor that makes up the gasifier features a rotor that is surrounded on all sides by blades. The air between the blades is forced out into the burner by centrifugal force as the rotor revolves. As a result, the burner's air pressure rises, and injecting the fuel into the burner causes it to burn, increasing pressure even more.

4. Car Engine Based on Ignition Type

Car engines can also be classified based on the type of ignition. The types of engines are – 

• Spark Ignition Engine

In a spark-ignition engine, the cylinder head is fitted with a spark plug that produces an electric spark at the end of the compression stroke to light the fuel. Primarily, spark-ignition engines are used in petrol vehicles.

• Compression-Ignition Engine

The heat of the compressed air inside the cylinder ignites the fuel in these types of engines. However, a compression-ignition engine lacks a spark plug that would generate a spark. During the compression stroke, the air in the cylinder is compressed at a significantly higher pressure.

Additionally, the compression ratio is greater than that of a spark-ignition engine. At the conclusion of a compression stroke, fuel is injected, and because the compressed air is hot, the fuel burns. Also, compression ignition is a feature of diesel engines, and engines with hot spot ignition are not frequently used.

5. Car Engine Based on Valve Arrangement

The types of engines based on the arrangement of valves are 

• L-Head Engine

In an L-head configuration, the inlet and exhaust valves are placed next to one another and are controlled by a single camshaft. Here, the cylinder and combustion chamber form the shape of an inverted as L. Furthermore, except for V-8 L-head engines, which have two lines of valves, all of an engine's valves are placed in a single row.

The valve mechanisms of L-head engines are located in the block, making it simple to remove the cylinder head when the engine has to be overhauled. Despite being durable and trustworthy, L-head engines are not particularly well suited to greater compression.

• I-Head Engine

The valves in an overhead valve or I-head engine are found in the cylinder head. The valves of in-line engines are typically arranged in a single row. Also, in each bank of V-8 engines, the valves can be in a single or double row. However, no matter the configuration, a single camshaft controls every valve.

• T-Head Engine

The inlet and exhaust valves of the t-head engine are located on opposite sides of the cylinder. Thus, to run them, two camshafts are needed.

• F-Head Engine

This engine is a hybrid of an L-head and an I-head, with one valve typically located in the head and the other in the cylinder block. Also, the same camshaft drives both sets of gears.

6. Car Engine Based on Number of Strokes per Cycle

As per the number of strokes per cycle is concerned, car engines can be classified as – 

• 4 Stroke Engine

In terms of power, dependability, and efficiency, 4-stroke engines perform well. Four-stroke engines mechanically separate each event to reduce emissions from unburned fuel. Additionally, it does it by separating the two, greatly reducing carbon monoxide emissions. The 4-stroke currently holds the top rank in passenger vehicles thanks to this confluence of appealing characteristics.

• 2 Stroke Engine 

Although 2-stroke engines are widespread, neither vehicles nor light trucks are powered by them. Small engines with two strokes are used in scooters, lawnmowers, chainsaws, mopeds, dirt motorcycles, outboard marine engines, and other items. A 2-stroke engine is still a gasoline-powered internal combustion device, although they are not designed similarly to 4-strokes.

• An internal combustion engine is a heat engine specifically because it transforms heat from gasoline combustion into mechanical work or torque. To move the car forward, this torque is applied to the wheels.
• In this regard, cylinders and pistons in engines move up and down in metal tubes. This is somewhat similar to your legs moving up and down to press the pedals as you are riding a bicycle. 
• Similar to how your legs turn the crankshaft of a bicycle, pistons are connected to an engine's crankshaft via rods, which travel up and down to turn the crankshaft, which in turn moves the drive wheel of the bicycle or the wheels of a car.
• The engine of a car normally has between two and twelve cylinders, with a piston moving up and down in each of them.
• Furthermore, the hundreds of minutely tiny controlled explosions produced by blending fuel and oxygen and lighting the mixture are what move these pistons up and down. 
• The combustion or power stroke is what you call for each time the fuel ignites. The resulting mini-heat explosion and expanding gases drive the piston down the cylinder.
• Today's internal combustion engines are almost universally four-stroke engines (for the purpose of simplicity, the focus is only on gasoline engines here). Nevertheless, three more strokes—intake, compression, and exhaust—combine with the combustion stroke to push the piston downward from the top of the cylinder.
• Furthermore, oxygen-rich air is necessary for engines to burn fuel. Like the piston descends during the intake stroke, valves open to allow the piston to serve as a syringe, sucking outside air into the engine's intake system.

In summary, it is evident that each sort of automotive engine is based on its layout or cylinder structure. There are four different types of car engines if you look at them according to the layout. The four types are straight, inline, flat, and v engines.

Additionally, there are six different types of vehicle engines if the cylinder arrangement is taken into account. The twin, three, four, five, six, and eight cylinders are among them. Also, additional parameters for the classification of car engines are mentioned in the article.

However, it is essential to note that the type of engine chosen relies on the user's needs and goals. So, when looking for a car, it is advisable to decide on your preferences before selecting an engine.