Currently, there are such types of engines that have two turbines. However, due to their cost, not all car owners can afford such motors. To date, the most popular car engines, for which demand is growing every day, are Twin-Turbo and Bi-Turbo. Of course, not every motorist knows the difference between them, but at first glance it can be said at all that they are the same. However, this is not the case at all. Also, do not think that Bi and Twin are the same turbocharging system, identical in its properties and qualities, but with different names.

Twin-Turbo turbocharging system

In order to understand this system, it is necessary to clearly understand its principle of operation. The system generates the necessary air pressure, which must be pumped into the engine cylinders themselves. As the arrow runs along the tachometer, the engine loses its power, and the output of the turbine itself is rapidly declining. It was in order that the motor did not lose power, and the turbine output only increased, and a second similar turbine was built in.

Of course, the operation of such a system must be regulated independently or in a car service. Turbines can be switched on at the same time, but it is desirable to set the turbines so that one of them starts its work first, and as the speed on the tachometer increases, the second one starts to work. However, with such operation of the turbines, such a problem as a turbo lag arises. Also, do not forget that this system can be installed not only on V-shaped engines, but also on conventional inline engines.

Bi-Turbo turbocharging system

Bi-Turbo, like twin, has two turbines. However, they are distinguished from each other by two completely different turbines in terms of power. If in the first case two turbines have the same power, then Bi-Turbo has one standard turbine and one with increased power. These turbines do not need to be independently regulated. They are initially configured so that at the beginning of the movement the first ordinary turbine turns on, and when the tachometer needle shows an increasing number of revolutions on the tachometer, the second, more powerful turbine is turned on. This system provides not only fast, but also smooth acceleration of the car. In addition, such supercharging avoids turbos. Such a turbine, as well as Twin-Turbo, Bi-Turbo can be installed not only on a V-shaped engine, but also on a conventional in-line engine.

The difference between these systems

Firstly, Bi-Turbo creates a smooth and even start and acceleration, while Twin-Turbo reduces the maximum power of the engine.

Secondly, the Bi does not create turbo rams, which cannot be said about the Twin.

Thirdly, Bi-Turbo allows you to operate not only in the city and the highway, but also on racing tracks, while Twin-Turbo does not have such an opportunity.

So, we are waiting for AvtoVAZ to appear in model range and turbocharged engines

It allows you to increase engine power by increasing the amount of fuel injected into the cylinder per cycle. Since the middle of the 20th century, there have been cars that use two turbines at once - this arrangement is called Twinturbo, Biturbo, Double Turbo and other words. You can often find information about the fundamental differences between Twinturbo and Biturbo - separate articles provide definitions and the essence of unique structural elements. Let's try to understand the layout of these systems and we.

Turbocharging is increasingly used to increase engine power

Essence of the question

The most interesting point about this problem is that fundamental differences just doesn't exist. Biturbo and its counterpart Twinturbo are simply alternative names for the same two-compressor supercharging systems. Moreover, both Biturbo and Twinturbo involve the use of various variations of the technical part.

Various names were coined by well-known marketers automotive manufacturers to distinguish their products from many similar machines built using the same layout. Interestingly, the Japanese prefer their Twinturbo twin turbochargers, while European companies write Biturbo - this has happened historically. Cars come to our country from both parts of the world, so both the name Biturbo and Twinturbo are familiar to domestic consumers. Therefore, the dispute about the differences between the names of turbochargers can be considered untenable - but it will be interesting to learn about fundamentally different systems used in international practice.

Classics of the genre

If you know what turbocharging is, then you will understand that installing two turbochargers has its own difficulties. Both turbines of the Biturbo system must be installed on the same exhaust line, and a certain distance must be maintained between them. The problem is that the long-range turbocharger will receive less power and not work as efficiently. In the middle of the 20th century, this problem was solved quite simply - the second turbine in the Twinturbo layout had different bearing characteristics and the shape of the impeller. Due to this, it was possible to synchronize the operation of the two units and significantly increase engine power using the Biturbo system.

The Biturbo system is used less and less

However, practice has shown that the sequential arrangement of Twinturbo has several important drawbacks:

• The presence of a serious "turbo lag", that is, a speed range in which the turbines simply do not work;
• Enough big time response to gas supply;
• nearby turbine;
• Inconvenience of installation on V-shaped motors.

They tried to solve the problem in various ways. However, the most elegant and efficient engineering solution was proposed by Toyota, which made the inclusion of turbochargers of its Biturbo variant. On the low revs valves are closed and exhaust gases pass only through the small first turbine, easily spinning it and providing an early exit from the “turbo lag”. After reaching 3500 rpm, when the gas pressure is already becoming excessive, the electronics open a special damper, and the hot stream rushes to the second larger turbocharger, providing a significant increase in engine power.

Modern interpretation

However, with the mass distribution of V-shaped motors, the sequential Biturbo system began to be used less and less, since it was inconvenient to use it from a constructive point of view. Around the beginning of the 80s, an alternative Twinturbo layout was proposed, in which each turbine was assigned to several engine cylinders - as a rule, it was about one or another "half" of the block. could be located much closer to the intake and exhaust manifolds, which significantly reduced the level of mechanical and aerodynamic losses, and also increased engine power. In addition, the parallel Biturbo system, using compact turbines, made it possible to get rid of "turbo lag" and make the engine very sensitive to changes in fuel supply.

In most cases, the Twin Turbo parallel circuit uses a common intake manifold, which simplifies it and makes it less expensive to maintain, but limits the dynamic potential of the car. Therefore, as an alternative, a Biturbo layout with separate intake tracts and manifolds was proposed. Among other things, this made it possible to adapt the system for use on compact in-line engines, which were previously equipped exclusively with two turbochargers arranged in series.

However, the most interesting scheme Twinturbo suggested BMW company- its difference was in the location of the turbines in the collapse of the V8, and not on the sides of the cylinder block. Moreover, each of the turbochargers was powered by cylinders located on both sides of the engine! Despite the enormous difficulties that the engineers had to overcome, the result exceeded all expectations. Such an original Biturbo system reduced the length of the “turbo-jam” by 40% without compromising the reliability of the assembly. In addition, the stability of the engine has significantly increased and the intensity of its vibrations has decreased.

Not quite Biturbo

Sometimes the Twinscroll turbine is confused with the Twinturbo layout. The latter involves the use of one turbine, which has two channels and two sections of the impeller with different blade shapes. At low speeds, a valve opens leading to a smaller impeller - as a result, the turbocharger accelerates quickly enough and provides an increase in power without "turbo lag". However, as the speed increases, the pressure exhaust gases becomes redundant and the second valve opens - now only the large impeller is used. As a result, the car receives an additional increase in performance.

Of course, such a system has a slightly lower efficiency than the classic Biturbo. However, in comparison with a single turbine, the traction capabilities of the engine still increase. Of course, the Twinscroll layout is difficult to manufacture and is considered quite unreliable. However, it is now widely used in powerful cars- including as part of the Biturbo system.

Combine incompatible

If you know how a mechanical compressor differs from a turbine, you will understand why these two systems are considered incompatible - the first is driven by the crankshaft, while the turbocharger uses the energy of the exhaust gases and it is almost impossible to combine them. However, nothing is impossible for Volkswagen engineers - they included both nodes in their version of the Twinturbo system. The turbine runs constantly, while the compressor helps eliminate "turbo lag" at low revs. Subsequently, it turns off, but with hard pressing the accelerator pedal comes into action again, improving the engine's response to fuel supply.

The result of using this Biturbo variant was a significant achievement of the torque limit at low speeds, an acceleration of revs, as well as a decrease in response time to pressing the gas pedal. The difference with a simple Twinturbo is almost imperceptible for the driver - he only feels the easily predictable powerful dynamics and is not distracted by power failures or other problems. However, the system developed by Volkswagen proved to be very difficult to manufacture and unreliable. Therefore, at present, only one of the two boost options is used on cars of brands that are part of the group of companies.

Results

Summarizing the above, we can conclude that the differences between Twinturbo and Biturbo are only in the name. If you are really interested in different boost systems, you should look into parallel and series layouts. In addition, it would be useful to familiarize yourself in more detail with the differences between a turbocharger and mechanical supercharging and the advantages of their combined use.

twinturbo and biturbo what is the difference and what are the differences

Contrary to the beliefs of some "experts", the name of the system biturbo or twinturbo do not display the turbine operation scheme - parallel or sequential (sequential).

For example, at Mitsubishi car 3000 VR-4 turbocharging system bears the name TwinTurbo (twinturbo). The car has a V6 engine and it has two turbines, each of which uses the energy of the exhaust gases from its three cylinders, but they blow into one common intake manifold. U, for example, German cars there are systems similar in working principle, but they are not called twinturbo (twinturbo), but BiTurbo (BiTurbo).
On the Toyota car The inline-six Supra has two turbines, the turbocharging system is called TwinTurbo (twinturbo), but they work in a special sequence, turning on and off using special bypass valves.
The Subaru B4 car also has two turbines, but they work in series: at low speeds, a small turbine blows, and at high speeds, when it fails, a second larger turbine is connected.

Let's take a look at both systems now. bi-turbo (biturbo) and twinturbo (twinturbo), or rather, what they write about them in “these your Internets”:

bi-turbo (biturbo) - a turbocharging system, which consists of two turbines connected in series. In system biturbo two turbines are used, one small and the other larger. The small turbine spins faster, but high revs engine, a small turbine cannot cope with compressing the air and creating the necessary pressure. Then a large turbine is connected, adding a powerful charge compressed air. Consequently, the delay (or turbolag) is minimized, and a smooth acceleration dynamics is formed. Systems biturbo not a very cheap pleasure and are usually installed on high-end cars.
System biturbo (bitrubo) can be installed as on a V6 engine, where each turbine will be installed on its own side, but with a common intake. Either on an in-line engine, where the turbine is installed by cylinders (for example, 2 for a small and 2 for a large turbine), or sequentially, when a large pipe is first installed on the exhaust manifold, and then a small one.

twin turbo (twinturbo) - this system is different from bi-turbo in that it is not aimed at reducing turbo lag or leveling accelerating dynamics but to increase productivity. In systems twinturbo (twinturbo) two identical turbines are used, respectively, the performance of such a turbocharging system is more efficient than systems with a single turbine. In addition, if you use 2 small turbines, similar in performance to one large one, you can reduce unwanted turbolag. But this does not mean that no one uses two large turbines. For example, a serious dredge might use two large turbines for even more performance. System twin turbo can work both on V-shaped motors and on in-line ones. The sequence of turning on the turbines can vary, as well as on biturbo systems.

In general, for even more fun, no one bothers you to stick 3 (!) Turbines or more at once. The goal is the same as for twinturbo. I must say that this is often used in drag racing and never on stock cars.

Obviously, a turbocharger (aka a turbine) is installed on a car engine to increase its power. Currently technical progress allows you to use the BITURBO and TWIN-TURBO pressurization system to achieve this goal as fully as possible. Often the question arises, is there a difference between them? What is it: two different pressurization systems or two names for one system?

“BI” or “TWIN”

When twin turbo cars first started to appear, almost all of them were called BITURBO. With the passage of time and the development of progress, a system of sequential supercharging with two superchargers in series appeared, and behind it an even more advanced two-stage supercharging system. In all these cases, two turbines are involved in the process. Which of them, how to call it, is up to you - for this, read this article to the end.

As already mentioned, initially all these pressurization systems were called BITURBO. I note that even before the advent of sequential supercharging, cars with parallel turbines began to be called in a new way - TWIN-TURBO, then this name began to be applied to both sequential and two-stage supercharging. The situation was the same for world manufacturers: when producing a serial car, someone called the modern sequential supercharging BITURBO, and someone called the parallel type of supercharging - TWIN-TURBO. The automaker's decision was somewhat unpredictable. For example, Volvo S80/XC90 (B6284T/B6294T) R6 Twinturbo , BMW 335/535 N74 (V 12 TwinPower Turbo).

And that's not the most interesting part. The term "TwinPower Turbo" is also used by BMW for engines with a single twin-scroll turbocharger. This fact once again proves that the choice of one of these two names is due solely to the whim of the automaker and is not directly related to the design scheme. System BITURBO different from the system TWIN-TURBO only by the fact that they used to say BITURBO, and now TWIN has become fashionable. Of course, to be absolutely accurate, one must remember that the world's well-known automakers call their, often individually charged, versions at the factories - and therefore, as they write, they should be called that.

In confirmation of this simple-complex question, let's read what names the manufacturer gave to engines equipped with two turbochargers operating in a parallel boost scheme:

• Audi 2.7 Biturbo (V6 Biturbo, A6/S4/RS4)
• Audi 4.2 Biturbo (V8 Biturbo, RS6)
• Audi 4.0 TFSI (V8 Twinturbo/Biturbo, S6/RS6/S7/RS7/A8/S8)
• BMW N54 (R6 TwinPower Turbo, 135i/335i/535i/740i/Z4/X6/1M Coupe)
• BMW N63/S63 (V8 TwinPower Turbo, 550i/650i/750i/X5/X5 M/X6/X6 M/M5/M6)
• BMW N74 (V12 TwinPower Turbo, 760i)
• Mercedes-Benz M278/M157/M158 (V8 Bi-turbo, S500/CL500/CLS500/E550/GL550/S63 AMG/CL53 AMG/CLS63 AMG/E63 AMG/SLK55 AMG)
• Mercedes-Benz M275/M285/M158 (V12 Bi-turbo, S65 AMG/CL65 AMG/SL 65 AMG/ Maybach/Pagani)
• Porsche 3.6/3.8 Turbo (H6 Twinturbo, 911 Turbo/Turbo S/GT2/GT2 RS)
• Porsche 4.5/4.8 Turbo (V8 Twinturbo, Cayenne Turbo/Panamera Turbo)

Varieties BITURBO/TWIN-TURBO

Having understood that these two names are interchangeable, we can talk about different systems of two turbines. There are several types of BITURBO/TWIN-TURBO system:

• Parallel;
• Consistent;
• Stepped.

Let's talk about them in more detail.

Parallel boost system- a system of two turbines belonging to the same type and placed in parallel. In this case, the turbines operate simultaneously. The advantage of a parallel system is that in its case two small or medium turbines have less inertia compared to one powerful but large turbine.

Such a connection system allows turbochargers to evenly distribute gas flows among themselves during operation. Compressed air is first supplied by the compressors to a common intake manifold. This air can then be distributed to the cylinders, or, more rarely, supplied separately to each bank of cylinders. The parallel supercharging system is most commonly used in diesel V-twin engines, where each turbocharger is fixed to its own exhaust manifold.

Thus, with a parallel turbocharging system, the turbines operate at all engine speeds, and the so-called "turbo lag" becomes significantly smaller.

Sequential turbocharging system is a system of two completely identical turbines. At the same time, a significant difference in the operation of such a system is that one turbine functions constantly, and the second is connected to work only with an increase in the number of engine revolutions. In order for the second turbocharger to start on time, an electronic control circuit for its operation has been introduced into the system using special valve which makes this system more complex.

Staged turbocharging system is an the most sophisticated, efficient and modern implementation of the BI/TWIN-TURBO principle. Two turbines are combined into a two-stage system - small and large. They are installed in the intake and exhaust tract. During the operation of turbochargers, the exhaust gases and compressed air are valve-controlled. With an increase in engine speed, the simultaneous coordinated work of both turbines begins. In this case, the exhaust gas bypass valve opens, as a result of which some of them pass through a large turbine, and it spins more strongly. After reaching a certain level of pressure at the inlet, the turbocharger of a large turbine compresses the air (while the pressure is not yet sufficient). The compressed air then enters the small turbine compressor where the pressure continues to rise. In this case, the boost relief valve is still closed. When finally the engine reaches maximum load, the bypass valve is fully opened. The exhaust gases pass through the large turbine, which causes it to spin up to its highest frequency, but the small turbocharger stops moving at this time. At the inlet, a large compressor creates greatest pressure pressurization, and small, in turn, on the contrary, provides resistance to air currents. As a result, at some point the boost bypass valve opens and compressed air flows directly into the engine.

As can be seen from the foregoing, the two-stage BI/TWIN-TURBO system is specifically designed to keep the turbocharger as efficient as possible under all engine operating modes without exception.

A car is a mechanism that makes life much easier for a person, saves time and gives a certain comfort. Modern cars can be completely different purposes and modifications. For sports car enthusiasts and the like power plants, manufacturers produce units with powerful motors. These include engines with the type of turbocharging Twin-Turbo and Bi-Turbo.

What is the Twin-Turbo system?

The operation of the turbine is carried out in a certain way. Air from outside the car is forced and pumped into the engine cylinders. But, after the increase in engine speed increases, the operation of the turbine loses its efficiency. To eliminate this feature of the functioning of the turbine, the developers designed a system consisting of two turbines.

The operation of the turbines can be carried out in a mode individually selected by the owner of the car. They can work both in parallel and in series. In the second case, one turbine is connected at the moment of starting the engine and gaining speed, and the second one is connected at the moment the effective operation of the first one drops. Mutual work, in turn, provides a huge increase in performance and engine performance.

The Twin-Turbo system can work and be installed on V-type engines, in-line engines are also suitable, there is no particular difference in this fact. The main purpose of such an installation is to increase the performance of the car and a quick set of speeds.

The system has a certain list of disadvantages:

1. Prolonged response to the accelerator pedal.
2. Increased operation of the second, more powerful turbine and its premature wear.
3. The presence of a turbo lag, the state in which the turbines are not efficient.

On models of cars that participate in races or drag racing, 3-5 turbines are often installed according to the above scheme. The automotive industry does not provide such "excesses" for serial cars.

Bi-Turbo system

A similar system refers to a technique for improving the turbine by installing another one. In the Bi-Turbo system, one turbine has significantly larger size and power relative to the other. They can only be connected in series. At low and low engine speeds, the first turbine starts, and after increasing the pressure on the accelerator pedal, the second one is turned on.

At low load, the turbine that has weak power works, at increased speeds, a powerful one starts up. Due to this algorithm, the car works without failures and loss of power while driving.

Bi-Turbo can be installed on V-type and in-line type engines. In addition to the positive effect of working on the engine, the installation can also carry unpleasant moments. First and foremost, not many people can afford it due to its high cost. The second is complex commissioning and installation work. They are quite specific and require equipment, tools and a knowledgeable craftsman. Most often, the installation can be found on expensive supercars from well-known global manufacturers.

What is the difference between Twin-Turbo and Bi-Turbo?

Both units are designed to improve the efficiency and performance of a car engine when under load. In addition, they both consist of two turbines that are installed directly in engine compartment car.

The Bi-Turbo system is considered better than its Twin-Turbo counterpart. Its design includes two turbines, which have different options size and power. They give the car the advantage of even acceleration, without loss of power and the appearance of “dips”. The main hyperfunction of Bi-Turbo is its smooth operation and excellent start without jerks and delays. The system can be used on cars designed for city driving.

The Twin-Turbo plant is a system of two turbines of the same size and power. A clear advantage is that the synchronous operation of the turbines ensures that the maximum potential and power is taken from the car's engine. A negative quality is considered to be the presence of a turbo lag, the so-called failure, which occurs due to failures and delays on the part of the accelerator pedal. Similar nuances are expressed in high-speed driving mode. The driver feels a sharp jolt at the start, and when shifting gears.