The most common engines onmodern cars are considered inline and V-shaped. Opposite motors are used much less often, mainly on models Porsche and Subaru. What is the reason for this inattention, and what advantages does the opposing engine have?
Design options
From its fellow, this motor is different in thatThe cylinders in it are not vertically or at an angle, but horizontally, i. e. in opposite directions from each other. Hence the name - opposite or horizontally opposite engine.
There are two options for the design of such motors.First, the pistons move towards each other and have a common combustion chamber. Such engines are push-pull. To their pluses, one can attribute a high quality of gas exchange, a design that is simpler than a row or V-type engine. 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 move the tank to a different view, it was enough to move a special lever on the high-pressure fuel pump and set the required angle of ignition. The engine was equipped with two turbines: a supercharger, which increased power, and gas, which led the exhaust gases out. The disadvantages of these opponents are the same as for two-stroke engines: higher fuel losses through the exhaust pipe. To this, as you might guess, decent dimensions are added, as for the pistons moving towards them, two crankshafts are required. The second option is more common. This is what we most often mean when we mean the opposing engine. Relatively speaking, this is a V-shaped motor, whose cylinders were decided to expand at an angle of 180 degrees. It is also used on cars (Porsche, Audi, Subaru), and on motorcycles ("Dnepr", "Ural"). We'll talk about it below.
Advantages and disadvantages
So, the advantages.The main advantage of this engine arrangement is the lower center of gravity, due to which the car's handling is improved. Also, the opposer favorably differs in terms of size and weight. It is noticeably shorter and lower than the in-line engines. Another advantage - an excellent balance, which is due to the arrangement of the pistons, neutralizing the vibration of each other. The shift of the center of gravity of the power unit to the center of the car makes it possible to make the turn more accurate and stable. This is especially important for sports models, where controllability is not just on the first, but in the very first place. There are pluses and frontal collisions. Since the opposing engine is located low, then in a collision, it will move under the cabin, and not into the interior of the car. So the presence of such an engine speaks in favor of the safety of the machine.
Does the opposing engine have disadvantages?Yes, and quite significant. They are the reason why such motors are not widely used. Opposites have a small length and height, but the width of them is much larger than that of the engines where the cylinders stand in a row or in the form of a letter V. This creates a lot of problems for designers. Engine compartment should be such that the opposing engine fits into it in width. In this case, you need to compactly position the steering and steer wheels. Another problem is the availability of nodes for maintenance. If the oil in the engine can still be changed on its own, then the remaining operations can only be performed by a specialist. Even spark plugs in the engine can not be changed independently, because it is easy to damage the cylinder head. These drawbacks make opposing engines more expensive in manufacturing and maintenance. And this, in turn, affects the price of the car.
As you can see, this type of device has enoughmerits, and shortcomings. However, their competitors are also not ideal. Therefore, when choosing a car, determine whether it is so important for you the complexity and costliness in servicing the power unit. It is possible that a good handling car will pay for these costs with interest.
