What is the difference between an atmospheric engine and a boxer one. The principle of operation of a boxer engine, advantages and disadvantages

Boxer engine- a special type of power plant, reminiscent of a traditional internal combustion engine, in which the cylinders have a special arrangement - horizontal. Such units are popularly known as "boxers". The motor received such a nickname due to the fact that the pistons move either from each other or towards each other. In this case, the pair of pistons is in one position, for example, from the bottom.

The very first sample appeared in 1938 thanks to the efforts of the Volkswagen automobile company. Then the unit was a 4-cylinder boxer, the volume of which was 2 liters. The maximum power of the power plant reached 150 horsepower.

The boxer motor is very widespread. Today, such eminent automobile concerns as Subaru and Porsche are engaged in the production and installation of the unit. Previously, it was possible to find the engine on models from Toyota, Volkswagen, Honda, Ferrari. Similar installations are used in motorcycles, Ikarus buses and some military equipment (for example, tanks).

The principle of operation of the boxer engine and its structure

To fully understand what a boxer engine is, you need to familiarize yourself with its structure. As noted above, this is an internal combustion engine with a special structure - a pair of pistons moves in a horizontal plane (not up and down, but from left to right). The second, adjacent one, is in the same position.

The number of such cylinders varies from 2 to 12 (their number is always a multiple of two). The most common designs have 4 and 6 cylinders. 8- and 12-cylinder engines have been developed for sports cars. Professionals note that the principle of operation of 2 and 4-cylinder boxers is no different from traditional engines. Those with six cylinders have their own characteristics.

Types of boxer engines

The principle of operation of the boxer engine also varies depending on the features of its design. Even such a simple unit can have several variations in the operation of the pistons. Therefore, the following types of motors are distinguished:

Boxer boxer often used in the production of Subaru cars. How does the boxer engine of the claimed type work: the pistons are located at a predetermined distance opposite each other, for example, if the first is fixed at a certain distance from the engine axis, then the second will take a similar position. Moreover, they are located each in a separate cylinder. The described principle of functioning resembles a boxing match, hence the name of the type.
OROS has a completely different principle of construction and the order of operation of the pistons. Such devices are push-pull. One cylinder has two pistons at once, which are attached to one crankshaft. The first is responsible for the intake of the mixture, the other for the timely release of combustion products. This design does not have a head, which is often found on the cylinder block. The advantages of the OPOS boxer engine are that the pistons function in favor of a single crankshaft. This type of device is lightweight and smaller. Consequently, the scope of application has expanded significantly. In addition, the specified engine can operate on different fuels - diesel or gasoline. Finally, we will point out the main advantages:
- the pistons travel a much shorter distance, as a result of which the friction force is significantly reduced, which negatively affects the wear resistance;
- efficiency increases, because harmful gases do not affect the combustion chamber, but put pressure on the pistons;
- motor is 30-50% lighter than usual;
- the boxer engine has fewer parts (50% on average);
- profitability;
- lack of a valve drive system.
- the motor takes up much less space under the hood.
However, it is worth remembering that the OROC is under development, so many unforeseen problems may arise during operation.
Tank engine(5TDF, designed specifically for the T-64 and T-72). The resource of the boxer engine is designed for large military equipment. Here, the pistons split one cylinder and move in the same direction, but each has its own separate crankshaft. The place where the fuel ignites (combustion chamber) occurs when the gap between the pistons becomes minimal. As with OROC engines, air is admitted into the cylinders, and unnecessary gases are removed by means of turbocharging. The counter stroke of the pistons made it possible to design a compact but powerful unit. The power plant has a maximum number of revolutions of 2000, and a capacity of 700 horsepower. The volume, respectively, reached 6 and 13 liters.

Advantages of a boxer engine

Each element in the automotive body has its own advantages and disadvantages. The advantages of a boxer engine are as follows:

lowering the center of gravity of the vehicle, which has a positive effect on its stability;
the resource of the motor will certainly increase (if properly operated, it reaches about 1 million km);
due to the special interaction of the pistons, the level of vibration and noise emission is reduced.

Cons of a boxer engine

If the boxer engine has advantages, then there are certainly certain disadvantages:

costly self-service - requires the involvement of professionals;
expensive and complex repairs, because the components are distinguished by their increased cost;
high cost of the power plant;
the complexity of the design;
increased oil consumption during operation.

Despite the disadvantages described above, many automakers equip their models with just such units. Development companies carefully weigh all the pros and cons before using this particular type of motor. The main advantage is great opportunities and broad prospects.

So, all negative aspects, in fact, boil down to expensive maintenance, which can affect the choice of most motorists not in favor of the units presented. However, major manufacturers (Porsche, Subaru) believe that quality requires a large investment in service.

For example, the Japanese carmaker is not going to return to traditional internal combustion engines, because they believe that in this case they will take a step back in terms of technology. Since car models have proven themselves only in the best possible way, the level of sales does not depend in any way on service rates.

Difficulties in the repair and maintenance of a boxer engine

It is important to note that often the positive aspects of these motors are noticeable only in power units that have six cylinders, but 2 and 4-cylinder do not differ much from traditional internal combustion engines.

If it is necessary to carry out some manipulations with this type of engine, then you certainly need to contact a specialist in a car service. You can only change the oil on your own. It is even better to entrust the replacement of spark plugs to professionals; beginners will easily harm the cylinder head. Full repairs are carried out only at special service stations.

Timely and systematic decoking can extend the service life. This procedure involves cleaning the surface of the combustion chamber, valves and pistons from carbon deposits. The operation is carried out in the autumn season or in March, when it is also very reasonable to check the engine oil.

In the material, we examined what the concept of "opposed engine" means, described the principle of operation, possible pros and cons. We hope that this will help determine the choice of not only the motor, but also the future car model on which a similar power unit can be installed.

When choosing a new one or buyers pay special attention to the engine installed in the vehicle. Moreover, they are interested not only in power and torque, but also in the type of construction itself.

Of all the engines available and used on modern cars, sometimes the largest number of questions is caused by opposed power plants.

Many have heard about boxer engines, but not everyone understands exactly what it is, what strengths and weaknesses such motors have and where they are used.

Features of boxer engines

Before talking about the principle of operation of a boxer engine, you need to find out what this boxer engine means and what features it is characterized by.

Boxer engines or boxers are called a variety of power plants, which are in many ways similar to classic or traditional internal combustion engines. But, unlike other ICEs used on cars, the arrangement of the cylinders in the boxer version is not entirely standard. Here they stand horizontally.

A distinctive feature of such automobile engines is the non-standard camber angle of the working cylinders. It is 180 degrees. In this case, the pistons carry out their movement in a horizontal plane, while being mirror-image relative to each other. That is, these pistons reach their top dead center at one moment, simultaneously. It is this nuance that is considered the main distinguishing feature of boxers in comparison with more traditional or classic V-shaped internal combustion engines, where the pistons move synchronously. When one of them reaches its top dead center, the other reaches its bottom.

This arrangement made it possible to obtain a low center of gravity, to reduce the height of the motor itself. That is, the boxer engine can be confidently called flat, which allows it to take up significantly less space in the car's engine compartment.

Also, the use of a pair of gas distribution mechanisms can be attributed to the distinguishing points, although the crankshaft is often still one.

The name boxer has become popular among motorists. This name for the boxer is explained by the fact that the pistons move, as it were, into each other, that is, towards each other. In this case, a pair of working pistons are located in one position.

For the first time, boxer motors became known back in 1938. Engineers from the German company Volkswagen made their efforts to develop a new type of internal combustion engine. At that time, they introduced a 4-cylinder boxer engine with a displacement of 2.0 liters. The maximum power of such an installation reached an impressive 150 horsepower at that time.

Gradually, opposed internal combustion engines began to spread actively. As a result, they were installed on:

cars;
sports models;
motorcycles;
buses;
military equipment, etc.

Currently, opposed installations are not very popular. And there are objective reasons for this.

Design and principle of operation

Studying the device of the opposed one, it is worth noting that it differs from other internal combustion engines precisely in its structure. Here, a pair of pistons move in a horizontal plane. That is, it does not happen from bottom to top, but from left to right.

Boxers always have a paired number of cylinders, and their number varies from 2 to 12. The most common motors are equipped with 4 and 6 working cylinders. When it comes to sports cars, then 8 or 12 cylinders are provided for them.

If we talk about how the boxer engine works, then experts do not see a significant difference in comparison with traditional internal combustion engines. Only the working 6-cylinder versions have a number of distinctive features in terms of the work carried out.

The horizontal placement of the working cylinders plays an important role here. This significantly reduces vibration and ensures a smooth ride. This is due to the fact that when the installed pistons move in the opposite direction relative to each other, they mutually neutralize vibrations. This ensures a smooth increase in power, there are no strong jerks. Plus, this factor has a positive effect on the rate of wear of the motor.

The boxers also have an excellent effect on the stability and quality of the car's handling, since the horizontal placement of the cylinders used allows the motors to be installed closer to the car chassis. This contributes to a low center of gravity.

Varieties

In many ways, the principle of operation and some design features depend on the specific type of opposed power unit.

There are several main categories of horizontally opposed engines:

boxers;
OPOC;
tank motors.

Boxers are most widely used in the equipment of passenger cars. The main user of such motors is the Japanese auto company Subaru.

In such a boxer, the pistons are located at a certain distance relative to each other and stand opposite. If the first piston is fixed at a certain distance from the motor axis, then the second one will also occupy the same analogous position. In this case, in the motor, each piston is placed in its own separate cylinder. By visualizing the operation of such a motor, one can imagine a duel between two boxers. Hence the corresponding name.

As for other engines of the OROS type, here the design principle and the operation procedure carried out by the pistons is somewhat different. These are two-stroke power units. One cylinder has 2 pistons at once, fixed on one crankshaft. In this case, the first is responsible for the inlet of the working air-fuel mixture, and the second, at the same time, promptly removes the resulting combustion products.

A special feature of OROS engines is the fact that there is no head, which is usually installed on the cylinder block. A plus of such a unit is in the operation of pistons on only one crankshaft. The boxer is small in size, requires less space and has a small mass. This made it possible to use the motor in various fields and on various vehicles.

EPOC can operate on two types of fuel, i.e. diesel fuel and gasoline. Its advantages also include:

when performing their work, the pistons pass a slightly smaller distance, which significantly reduces the friction force and minimizes wear;
increased efficiency, which is due to the absence of harmful effects of exhaust gases on the combustion chamber. They apply pressure to the working pistons;
when compared with classic engines, the mass of the OROC will be 30-50% less;
a boxer motor of this type uses fewer elements. When compared with in-line and V-shaped, the difference will be 40-50% on average;
such power units are quite economical;
The design does not use a valve drive system;
less space is required to place the unit in the engine compartment.

But not everything is as rosy as it might seem at first. This type of engine is under development and gradual improvement. It is too early to talk about any real and global successes, since there are a number of hidden and unforeseen problems that arise during operation.

Now for the third type of boxer engine, which is called a tank engine. This is a power plant marked 5TDF. The engine was created specifically for the T-64 and T-72 series tanks.

The tank boxer has an impressive resource, since it was originally designed for installation in large military equipment. The pistons divide one cylinder and move in the same direction, although each has its own separate crankshaft.

The space for ignition of the air-fuel mixture is created by creating a minimum gap or clearance between the two installed working pistons. As in the case of OROC, air enters the cylinders here, and the exhaust gases escape due to the operation of the turbocharging system.

Due to the counter stroke of the working pistons, the engineers managed to create a power unit that is compact in size, but impressive in its power. The maximum for a tank boxer reaches 2 thousand. The power of the unit is 700 horsepower. The working volume of the engine can be 6 and 13 liters.

The tank boxer can operate on gasoline and diesel fuel. This is a domestic development that at one time managed to impress. But at the present time, THF is no longer produced.

Advantages and disadvantages

To fully reveal the features of this motor, you need to look at its strengths and weaknesses.

Let's start with the most relevant benefits of boxer engines. Its advantages include the following points:

what is really good about a boxer engine is the best possible location variation. The engine is always low, which is much better than the classic internal combustion engine. This allows the center of gravity to be lowered. This improves stability and controllability;
also the boxer is the best among competitors due to being virtually on par with the transmission. This feature makes it possible to minimize losses during transmission of torque;
A strong argument in favor of a boxer engine is the minimum level of vibration, even when the car is moving at maximum speeds. This advantage is due to the location of the cylinder-piston group. Thus, the engineers created the perfect balance and were able to ensure effective damping of all potential vibrations. From this, the engine runs smoothly, there are no jerks;
design features and balance made it possible to use not 5, but only 3 bearings for the crankshaft. Due to this, it became shorter and lighter;
among all its competitors, the boxer is the undisputed leader in terms of providing passive safety. Even in the event of a severe head-on collision, the engine will not penetrate into the passenger compartment. On impact, it simply falls without damaging the driver or passengers. This feature has managed to save more than one thousand lives;
if the boxer engine is properly serviced, regardless of the type of fuel used, the boxer engine will boast a huge resource. With the right attitude, such an engine serves about 1 million kilometers. To achieve this result, you just need to change the oil and other consumables on time, and also not to expose the unit to excessive extreme loads.

While the list of benefits has proven to be impressive, the boxer engine also has significant drawbacks. And these disadvantages are largely capable of overriding all the existing advantages.

Costly self-service. The car owner of a car with an boxer engine will be able to perform only a number of simple procedures during the maintenance process. Most of the work will have to be carried out with the involvement of specialists. And this is the additional cost of maintaining the vehicle.
Expensive and difficult renovation. The complexity of the repair provokes an increase in the cost of services. The spare parts themselves are quite expensive. Plus, you have to look for competent specialists. There are very few professionals in the field of boxer motors. And those who work with such power plants ask for quite a lot of money for their services.
Complex construction. To perform certain work and change some consumables, sometimes you have to partially disassemble the engine. This is problematic and unavailable for.
Conditional compactness. Although such motors were made small and placed low, they still require quite a lot of space under the hood.
Active oil consumption. In opposites, it is extremely important to monitor not only the condition, but also the amount of oil. The motor has a good appetite for lubricant. If fasting begins, it will lead to extremely negative, serious and costly consequences.
Removable cylinder liners. The fact that they are removable is a positive thing. But to replace the liners, you have to carry out a number of complex measures for the partial disassembly of the motor. If this is not done, soon the engine will begin to consume oil even more actively, which will eventually lead to a rapid failure of the entire boxer engine.
An acute shortage of skilled craftsmen. For Russia and the CIS countries, this is one of the main problems. Many people would love to buy a car with a boxer engine. But a large number of questions are raised by the fact that there are no good masters. There are those who take on the service of opposing players, but the quality of their work leaves much to be desired. Skilled craftsmen are expensive and do not work in every city.

Boxer engines can be called internal combustion engines with excellent capabilities and bright prospects. There is still room to strive for. Therefore, automakers who are really interested in boxer engines are constantly trying to come up with something new, introduce fresh ideas and fight against objective shortcomings.

Application area

Considering all the information considered, the presence of significant advantages and objective disadvantages, a natural question arises as to what machines can be found on the boxer engine.

It should be fair to say that cars are not as often equipped with boxer engines as traditional in-line or V-shaped power plants.

But there is one car company that has been successfully and actively installing these types of engines on its models for more than fifty years. Moreover, it is largely thanks to this manufacturer that the segment of boxer motors is developing. This is the Subaru company, which is based in Japan, but its cars are successfully sold all over the world.

But there are still a few cars and vehicles that are equipped with such power plants. We are talking about the following vehicles:

some models of the Volkswagen auto concern;
several cars from the Porsche brand;
Soviet-style motorcycles Ural;
motorcycles Dnipro;
Ikarus buses from Hungary.

There is no need to talk about some kind of global distribution of this type of engine. Although the sales volumes of the same Subaru cars with boxer power plants are impressive.

Recently, boxer motors have again attracted the attention of engineers and developers. Research and all kinds of tests are carried out on a regular basis. Specialists strive to improve and modernize such engines. Moreover, a group of American specialists, whose work is financed by Bill Gates, is directly related to the revision of the OROS-type motors.

It is difficult to say what will come of all this. But the fact of interest in opposites hints to us that soon it will be possible to solve the problem of obvious shortcomings. In this case, in-line and V-shaped internal combustion engines will have a real and serious competitor. If the opposing player gets rid of its shortcomings and maintains its key advantages, it will take a huge step forward.

But so far everything is at the level of partial rumors, guesses and conjectures. Whether it will be possible to significantly change the boxer motors in the near future is a difficult question.

How to avoid costly repairs

Given all the shortcomings, we can conclude that boxer motors are expensive and difficult to repair. The main costs are associated precisely with the purchase of spare parts and payment for the services of repairmen. If you keep the engine in good working order, you won't have to spend a lot of money on it.

This is the main mission of a car owner who wants to buy a car with a boxer, but is afraid of the potential costs of servicing it. There are several rules, the observance of which will allow you to get the maximum benefits and face the minimum manifestation of the disadvantages of the boxer type engine.

Maintenance intervals. Strictly follow the regulations, carry out maintenance according to the manufacturer's recommendations. In the conditions of our roads and climate, it can be slightly reduced. If the machine is operated in difficult conditions, a minimum of 15% should be subtracted from the declared maintenance interval.
Qualified craftsmen. Although there are not many experienced boxer engine specialists, it is quite possible to find them. Trusting the engine to a skilled technician will greatly increase your chances of long-term trouble-free operation of your boxer power plant.
A careful approach to the choice. Since boxers are very demanding in terms of engine oils, the recommendations of the automaker must be strictly followed. Choose oils that the plant advises to use. The relevant information can be found in the instruction manual. If it is impossible to buy just such a brand, then focus on well-known manufacturers with a good reputation. Buy lubricant for a boxer motor only in trusted stores, where there are all guarantees and quality certificates. This will avoid acquiring a fake.
Refuel at good gas stations. This advice applies to all engine types, not just boxer ones. Good fuel ensures efficient operation of the engine, extends its resource, and reduces the risk of contamination. Even if you pay more for fuel than at cheap gas stations, you can still save money. This will manifest itself in the form of reliability and the absence of the need to repair the engine due to the negative impact of low-quality fuel.
Cooling system. Although boxer motors are equipped with a fairly efficient cooling system, even this cannot cope with excessive engine overloads. Do not overload the boxer. And for the system itself, choose only high-quality consumables.
Washing the engine. It needs to be carried out periodically, and not on an ongoing basis, as many might think. But even a rare cleaning of the engine will normalize heat transfer and prevent overheating. Hence the long service life of the motor, the preservation of its service life and the absence of problems.

Do not believe the long-standing stereotype that supposedly operating a car with a boxer engine is much more expensive than maintaining a car with a traditional in-line or V-type internal combustion engine.

This is clearly seen on the example of Subaru cars. Their spare parts are relatively inexpensive; consumables also do not cost huge amounts of money. Even a person with a low income level can maintain such a car. Everything directly depends on the quality of service and proper care. If you properly maintain the car, carry out scheduled work on time, and also not provoke extreme overloads, the engine will not require a lot of money.

Boxer motors are of great interest given their strong qualities. To some extent, they are embarrassed by their shortcomings. But they are rather arbitrary. Any engine can lead to huge financial costs. This is already a question directly to the owner and his attitude towards his car.

The most common engines on modern cars are in-line and V-shaped. Boxer engines are used much less frequently, mainly on Porsche and Subaru models. What is the reason for such inattention, and what are the advantages of the boxer engine?

Design options

This motor differs from its counterparts in that the cylinders in it are not located vertically or at an angle, but horizontally, i.e. in opposite directions from each other. Hence the name - boxer or horizontally opposed engine.

There are two design options for such motors. First, the pistons move towards each other and have a common combustion chamber. Such Their advantages include the high quality of gas exchange, a simpler design compared to in-line or V-shaped motors. Similar devices were used on military equipment, in particular, on Soviet T-64 tanks, which could operate on different types of fuel: kerosene, gasoline, diesel fuel. To transfer the tank to a different view, it was enough to move a special lever to and set the required ignition angle. The engine was equipped with two turbines: a supercharger, which increased power, and a gas, which removed exhaust gases outside. The disadvantages of such boxers are the same as those of two-stroke engines: higher fuel losses through To this, as you might guess, decent dimensions are added, because two crankshafts are required for the pistons moving towards them. The second option is more common. This is what we most often mean when we mean a boxer engine. Relatively speaking, this is a V-shaped engine, the cylinders of which were decided to be expanded at an angle of 180 degrees. It is used both on cars (Porsche, Audi, Subaru) and on motorcycles ("Dnepr", "Ural"). We will talk about it below.

Advantages and disadvantages

So the benefits. The main advantage of this engine layout is a lower center of gravity, thanks to which the car's handling is improved. Also, the boxer compares favorably in terms of size and weight. It is noticeably shorter and lower than in-line engines. Another advantage is excellent balance, which is ensured by the arrangement of pistons that neutralize each other's vibration. The shift of the center of gravity of the power unit to the center of the vehicle makes it possible to make the turn more precise and stable. This is especially important for sports models, where handling is not just the first, but the very first place. There are advantages to head-on collisions. Since the boxer engine is low, it will slide under the cab in a collision rather than into the passenger compartment. So the presence of such a motor speaks in favor of the safety of the car.

Does the boxer engine have disadvantages? Yes, and quite substantial. It was they who became the reason that such motors were not widespread. Boxers are small in length and height, but they are much wider than engines, where the cylinders are in a row or in the form of the letter V. This creates many problems for designers. The engine compartment must be such that the boxer engine fits in its width. In this case, it is necessary to compactly arrange the steering and steered wheels. Another issue is the availability of nodes for service. If the engine oil can still be changed independently, the rest of the operations can only be performed by a specialist. Even the spark plugs in the engine are not recommended to be changed on your own, because the cylinder head can be easily damaged. These disadvantages make boxer engines more expensive to manufacture and maintain. And this, in turn, affects the price of the car.

As you can see, this type of device has both advantages and disadvantages. However, their competitors are also imperfect. Therefore, when choosing a car, decide whether the complexity and high cost of servicing the power unit is so important to you. It is possible that the good handling of the car will more than pay off these costs.

One of the most interesting internal combustion engines: the boxer engine operating principle, its design features, advantages and disadvantages.

The boxer engine is a design with two rows of cylinders horizontally located relative to each other.

The palm in the development of this type of engine is carried by the Volkswagen automobile concern. Its development was completed back in 1938 and it was installed on the most legendary in the world, the people's car Volkswagen Käfer.

Volkswagen is currently putting the boxer engine on the prestigious 997 Porsche cars

In the forties of the last century, the Japanese concern Subaru (SUBARU) also developed an opposed engine design. He also advanced in his developments and today equips a whole range of engines with such engines.

In developing this design, the engineers sought to lower the vehicle's center of gravity, thus achieving greater stability.

Features of the boxer engine

The main feature is the arrangement of two rows of cylinders, strictly in the same plane, at an angle of 180 degrees relative to each other.

There are several types of boxer engines:

OPOS - Opposed Piston Opposed Cylinder in translation Opposite piston cylinder... The idea of this design involves the movement of pistons towards each other, being in one cylinder;

Boxer - Boxer. Classic modern boxer engine. The pistons are like boxers in the ring, alternately waving their fists, then one, then the other. One at top dead center, the other at bottom dead center and always equidistant from each other;

5TDF. This is already a domestic development. This boxer engine was made for the T-64 and T-72 tanks. Its design is special, it is two-stroke, has two crankshafts and pistons move towards each other.

Boxer engine advantages:

The first and foremost advantage is that there is almost no vibration. The movement of the pistons in different directions maximally balances the forces that arise when the vector of movement of the pistons changes. This affects not only comfort, but also the service life of such an engine;
Resource. It is this arrangement of the cylinders that gives the surprisingly high resource of the boxer engine. They nurture over 500 thousand km. You can find a lot of SUBARU cars with a mileage of up to 900 thousand km. without major repairs;
The center of gravity. This is very popular with sports car designers. A low center of gravity naturally gives more stability and is extremely useful for racing, although this advantage is equally appreciated in production cars;
More space under the hood. Although this is compensated by the inconvenience of having to free up space on the sides in order to assemble it without greatly expanding the hood and front suspension.

Boxer engine disadvantages:

High maintenance cost. Even spark plugs cannot be replaced at home. If we talk about the most common brand of boxer - Subaru, then among its various engines there is practically no interchangeability of parts;
Very complex overhaul. Due to the unusual and original design, repairs are carried out only in specialized workshops, of which there are not so many;
High consumption of engine oil, which is associated with the design of the boxer. And of course, the crankcase clogs up faster, due to the large oil flow through the engine.

//www.youtube.com/watch?v=9LBEK-uw7cE

A boxer engine is a modified unit with a structure different from a conventional in-line engine. Its pistons are at a rotated angle, so the vapors move towards and back. The adjacent pair, located along the axis of the plane of the motor, moves identically, but with a small time interval, providing the engine's stroke. The movement of the pistons inside the engine remotely resembles a boxing match, therefore this type of internal combustion engine is called a boxer.

Operating principle

Based on the design of the unit, each piston is installed on the one intended for it. The number of cylinders is necessarily even, it ranges from 2 to 12. The most common engines for cars are motors with four and six cylinders.

In general, the principle of operation of this type of unit is similar to a conventional in-line motor. The difference lies in the fact that the pistons in it move horizontally, and not up and down, which is due to the horizontal arrangement of the cylinders. These types of motors are characterized by the presence of two cylinder heads located horizontally on both sides.

Motor applicability

Quite a lot of car models with a boxer engine under the hood drive on the roads. But there are only two leading companies that are engaged in the implementation and development of these units, namely Porsche. Although earlier these units were installed on such car brands as Honda, Ferrari, Chevrolet, Alfa Romeo and many others.

One of the classic flat-engine cars - Alfa Romeo 33

Models from the Porsche manufacturer, such as the Cayman and 911, are powered by six-cylinder engines, while the sportier variants are equipped with eight- and even twelve-cylinder forced engines.

Most seasoned car owners say that two- and four-cylinder boxer engines are virtually indistinguishable from their in-line counterparts, but the larger the number of cylinders, the more pronounced the difference.

A bit of history

The first serial diesel boxer engine was a motor produced by Subaru in 2008. It was a four-cylinder unit with a volume of 2 liters and a capacity of 150 horses. This engine received a fuel supply control system.

In Soviet times, tanks were equipped with one of the types of modern boxer engine, which has a similar principle of operation, but completely opposite to it in design. It contained 2 pistons per cylinder, which worked, moving towards each other. At the moment when the distance between the pistons was minimal, fuel entered the resulting combustion chamber between them. That is, if a modern engine has one crankshaft and 2 block heads, with piston strokes from each other, then the Soviet 5TDF had 2 crankshafts and 1 head with pistons moving towards each other. Also a feature is the two-stroke mode of operation of this unit and its versatility in terms of the fuel used. Initially, it was a diesel engine type, but it could successfully run on gasoline, kerosene, aviation fuel, and even fuel oil. On the latter, however, not very long. This versatility was due to the presence of a fairly high compression ratio in the cylinders.

After the production of T-64 tanks was discontinued, the engine was abandoned in favor of V-shaped configurations, considering the boxer engine resource-intensive and not convenient enough for further use.

The very idea of developing a boxer engine is not a merit of Subaru, as many think. Such units were installed on Ikarus buses, on a fairly large number of motorcycles (starting with domestic Dnieper and Urals, ending with BMW R1200GS, as well as similar ones). Naturally, like any development, the boxer engine has its pros and cons.

Pros of a boxer motor

The main advantages include the following qualities:

Due to the design, the center of gravity is shifted down. This greatly improves the handling of the vehicle, especially at high speeds. Although we do not have such roads where it could be verified without risk.
No vibration when working. This only applies to motors with 6 or more cylinders. In engines with two or four cylinders, secondary vibrations are not much lower than in conventional in-line engines.
Enough . It is believed that boxer engines have a resource of over a million kilometers.

Cons of the motor

Naturally, units of such a design have rather serious drawbacks, which the developers have not yet gotten rid of.

The maintenance cost is substantially higher than that of conventional motors. In addition, the opposed one is problematic, and sometimes almost impossible to repair yourself. It has a rather complex structure, so it is better to have it repaired by professionals. And this will cost a lot of money.
Due to the first drawback, the second one flows out smoothly. In small towns, you may simply not find a sufficiently qualified master who is guaranteed to provide service with proper quality.
The complexity of the design, as well as the greater number of elements, increases the cost of its spare parts several times, as well as their number.
High for a boxer engine is considered the norm. Moreover, it is so high that, with a similar flow rate, an ordinary unit must necessarily undergo overhaul. This leads to the situation when, unknowingly, the motorist simply did not control the oil level in the engine, which led to oil starvation. Given the horizontal arrangement of the piston, this can quickly lead to irreversible consequences.

Having got acquainted with how the boxer engine works, we can conclude that almost all the disadvantages of this type of engine can be attributed to the financial part, but for many car owners this is a rather serious factor taken into account when buying a car.

Representatives of the Subaru company believe that a return to standard types of engines would be a huge step back for them, so they are not going to change boxer engines for other models. According to them, neither the service price nor the price of the cars themselves affect the level of sales.

Boxer engines have been designed to save space under the hood. As a result, the unit is lower, shorter, but much wider. That is, from the vertical plane it was transferred to the horizontal one. That is, in fact, nothing has changed, except for the increased price, as well as the complexity of service. And as for the forced models with one or more turbines, their service life ranges from hundreds of thousands of kilometers to several hundred, not a million. The same applies to fuel consumption - it is about a third higher than that of a standard engine of the same power.

Given all the advantages and disadvantages of this type of engine, it is difficult to call them any technical breakthrough in terms of the automotive industry, but these engines also have their fans. Do you agree with us?