On some cars, opening the hood, you can see the abbreviation for the DOHC 16V engine. Few modern drivers know what this sign means. However, each car owner understands that such a power unit has increased power characteristics.
History of creation
For the discovery of the engine, which has gained worldwide distribution, it is necessary to thank the so-called "gang of four." That was the name of the association of talented and creative developers at Peugeot who created the DOHC engine. What it would be, they themselves did not yet understand. Just these daredevils were desperate racers and fans of cars that are capable of developing fantastic speed.
By that time, quite modern power units with a turnover of about 2,000 began to be installed in the car. However, the “gang of four” was not enough, and they decided to create a sufficiently powerful and very fast engine, which in addition would economically consume fuel. This design was first developed. The main author was a young man named Zuccarelli.
According to his idea, it was decided to slightly change the structure of the power plant and place camshafts over the valves. After testing, the need for intermediate elements disappeared with itself. The most difficult thing was to make the highest temperature of the working gas in the combustion chamber rise to around 2000 degrees. But even here, the designers were able to find a way out by completing the main parts from metals, which practically do not heat up. Thus, talented engineers were able to create a unique unit that is in demand today.
DOHC engine - what is it
Almost all drivers familiar with the structure of the internal combustion system imagine what a cam shaft looks like, opening when the valve rotates. With the help of the internal combustion engine and the gas distribution phases, fuel is launched / released. Previously, SOHC (Single Over Head Camshaft) system with one camshaft was installed on cars.
However, most vehicles are now converted to DOHC engines. The abbreviation is Double Over Head Camshaft. If you translate these words from English, it will become clear that the engine is equipped with two camshafts. In the professional environment, other abbreviations are also known: DVRV and DOSHTS. The DOHC power unit is equipped with a pair of camshafts, which is located in the cylinder head. Because of this, the shaft in such a motor is placed on top, above the rows of exhaust and intake valves. They do not have any transition elements, such as rockers, rods or rockers.
Features
The addition of 16v means that the number of cylinders is four, each of which has 4 valves. This was done in order to facilitate the design of the valves even more. Therefore, car designers decided to install exactly 4 pieces on each cylinder, and not two. This structure allows you to lighten the valves and increase speed by 1.5-1.6 times. In this case, the springs receive less load.
This design was invented so that through the two inlets with a small diameter, a larger volume of working fluid flows through than one. In addition, this structure allows the combustible mixture to burn much faster, and also increases the efficiency and efficiency of the entire motor system on the DOHC 16V engine.
Principle of operation
In order to ensure the correct operation of the two camshafts, we used a special gear belt - this is the same device with a set of gears or a chain. Of these 2 ways to drive, the belt is considered more economical, so most car owners choose it. It has several advantages:
- works quietly;
- it is not necessary to constantly lubricate it;
- It is inexpensive.
Among the shortcomings of a belt drive, the most important thing is that when it breaks, it can come across a piston. Because of this, both elements fly apart and can significantly damage the liner and cylinder block. In this case, it will not be possible to get off with minor repairs, so experts recommend checking the condition of the part regularly.
If a chain is used as a drive, then it emits much more noise, but it will be much more reliable. The downside of this device is stretching over time. To eliminate this drawback, you should purchase special mechanisms that perform automatic chain tension. You will also need to install a sealed housing for complete lubrication.
Benefits
Many drivers appreciated the advantages of the design, especially those who prefer a fast ride. Indeed, for a real rider, it is important that the engine develops speed faster. The engine can reach a speed limit.
In addition, the timing mechanisms are well combined with various conversion designs. Other advantages of the power plant are noiselessness, economy and lightness. Fuel economy when traveling by car is about 20-30%.
disadvantages
Despite the large list of advantages, the engine has several disadvantages. The most important shortcomings, according to car experts, are recognized:
- A sophisticated design device that regulates the blocks of the system responsible for gas distribution.
- The high cost of spare parts that are needed to repair a failed motor.
And not only spare parts are expensive. In order to repair the motor, you will need to turn to professional craftsmen, whose work is also not cheap. In addition, the engine will operate without interruption only on high-quality synthetic oil, otherwise damage to the hydraulic lifters may occur.
Reviews
Many auto experts believe that the dual camshaft engine is a real breakthrough in the automotive industry, so when choosing a car, they recommend the DOHC 16v engine. Customer reviews using a vehicle with a power plant of this type are fully consistent with this statement. Despite the fact that the maintenance of such a motor will cost the owner a lot, any costs will be partially offset by performance and low fuel consumption.
Modern options
Currently, such engines are ubiquitous. They are mainly used by such well-known manufacturers as Toyota, Hyundai, Mercedes, Ford, Chrysler, Honda and many others. The most popular configurations are 2.4 DOHC and 2.0 DOHC. The first engine has a volume of 2.0 liters. They began to be installed on Ford and Hyundai vehicles from the late nineties of the last century.
Toyota, Hyundai and Chrysler prefer to put power plants with a volume of 2.4 liters on their cars. Among the companies involved in the automotive industry in Russia, the positive qualities of the DOHC 16V engine were appreciated by GAZ.