Depending on the model and manufacturer, different types of combustion engines can be found in cars. In addition to the engine types frequently used in automotive engineering, such as the in-line engine and the V-engine, there are also some exotics. Find out now everything about the structure, differences, advantages and disadvantages of the different types of engines.

• In-line engines
• Boxer engines
• V-engines
• VR engines
• W engines

In-line engine as the most common engine in cars

In-line engines are among the most common engines found in cars. In this type of engine, all the cylinders of the engine are arranged one behind the other in a row. Each in-line engine has a single bank of cylinders, although the number of cylinders can vary. This type of engine is used in automobiles as both diesel and gasoline engines, and in-line engines with four, five or up to eight cylinders have been used throughout the history of the automobile. The latest development is concepts with three cylinders in line and turbocharging. These engines are considered particularly efficient and fuel-saving. Connoisseurs, on the other hand, appreciate designs such as the six-cylinder in-line engine for their particularly smooth running.

Four-cylinder in-line engines

For a long time, the four-cylinder in-line engine was considered the standard for passenger cars. Due to its design, the overall length of this type of engine with four cylinders is particularly short. Depending on the vehicle model and drive system, such an engine block can be installed either longitudinally or transversely to the direction of travel. It is therefore hardly surprising that this popular engine design has undergone continuous development, and in-line engines with multiple camshafts in the cylinder head and optimized fuel injection can now be found even in small cars. The advantages of in-line four-cylinder engines are their simple design and the fact that they are so inexpensive to manufacture. An in-line engine with many cylinders, on the other hand, can be prone to vibrations and oscillations in the crankshaft. In addition, the space required for in-line engines of this design increases.

Boxer engines in automotive engineering

A boxer engine is a form of internal combustion engine in which the cylinders are arranged at an angle of 180 degrees. Boxer engines are used with different numbers of cylinders in passenger cars and motorcycles. The four-cylinder boxer engine was used for a long time at Volkswagen, for example in the successful VW Beetle model. The sports car manufacturer Porsche has traditionally used boxer engines as six-cylinder units. Boxer engines are usually found as gasoline engines, but diesels also exist. One of the great advantages of the boxer as a gasoline engine is its smoother engine running, combined with greater smoothness. The disadvantages are the more complicated production and the associated manufacturing costs, as well as the increased space requirements. Enthusiasts still appreciate the special sound and responsiveness of this type of engine.

Two-cylinder boxer engine

Boxer engines with two cylinders are often used as motorcycle boxer engines. Here, the two laterally protruding cylinders offer many advantages and enable good cooling by the airstream, for example. However, the two-cylinder boxer engine was also used in the automotive industry in the past. Two-cylinder boxer engines can be found, for example, in the Citroën 2CV or the BMW 600 small car.

The V-engine as a drive for cars

V-engines are engines with two separately arranged cylinder banks. The two cylinder banks visually form the letter V due to their bank angle, which is where the name of these engines comes from. In cars, V engines are mostly found as V6 variants with six cylinders or as V8 engines with eight cylinders. In the past, there were also V4 engines with only two cylinders per cylinder bank. Alongside in-line engines, the V-engine is one of the most widespread designs in automotive engineering. In this design, the pistons of both cylinder banks are connected to a common crankshaft via connecting rods. The bank angle of the V-engine can vary depending on the engine model and can be up to 180 degrees. Unlike the boxer engine, however, two pistons share one camshaft crank.

V8 and V6 V-engine

In V8 and V6 engines installed in passenger cars, the bank angle is usually smaller. This results in the classic V-shaped appearance with the two characteristic cylinder banks. Each cylinder bank has its own cylinder head with separate camshaft and valves. This makes production more expensive and maintenance of the V-engines not insignificantly more difficult. Another disadvantage of the V-engine is the more complicated exhaust system with two exhaust manifolds and the more complex engine cooling system. The crankshaft and crankcase also have special design requirements. In addition, many components have to be duplicated due to the engine design. Compared with the in-line engine, however, the V-engine allows a larger number of cylinders to be arranged in a shorter design. And it is impossible to imagine American cars without the V8 engine with its special engine sound.

VR engine design

The VR engine is a special engine design. It combines the design features of the V-engine and the in-line engine. VR engines have only one cylinder bank, in which several cylinders are arranged offset to each other. Connecting rods link the pistons to the crankshaft via separate crankpins. A VR engine has a single cylinder head that houses the camshafts and valves for all cylinders. VR engines are used by various manufacturers in passenger cars. The best-known representative is the VR6 engine from Volkswagen, which was installed in the VW Passat model, among others. The angle of the cylinders to each other is smaller in these engines than in the classic V-engine. The design and production of this engine are considered to be more complicated. On the other hand, the design combines the short engine block of the V-engine with the narrow width of the in-line engine, which allows installation at right angles to the direction of travel.

Special case: W-engine

For a long time, the designation W-engine stood for engine variants with three cylinder banks. The Volkswagen Group took up the term at the turn of the millennium. From then on, VW referred to its newly developed engines with several VR cylinder banks and a common crankshaft as W-engines. The concept allowed eight or twelve pistons to be accommodated in a small installation space. Strictly speaking, the Volkswagen Group’s W engine is a double VR engine. For this purpose, VW’s designers arranged two VR cylinder banks at the same angle as in a V-engine. The eight-cylinder W-engine installed in the VW Passat is composed of two VR4 cylinder banks. Volkswagen also developed a twelve-cylinder W engine for the VW Phaeton. This model is in turn based on two cylinder banks of the VR6 engines. A similarly designed W engine with a total of sixteen cylinders was installed as a mid-engine in the Bugatti Veyron sports car.