Bi-turbo
TechnologieAverage price
2500€ - 10000€
Bi-turbo technology, also known as "twin-turbo", is an engine supercharging system that uses two turbochargers instead of one. The main objective is to increase engine power and torque while reducing response time, or "turbo lag", often associated with large single turbochargers. There are several configurations of bi-turbo systems. The most common on V-engines is the parallel setup, where each turbocharger is fed by half of the engine's cylinders. Another configuration is the sequential setup, which uses a small turbo at low revs for quick response, and a larger turbo that takes over at high revs to deliver maximum power. This latter configuration provides a very broad and linear power curve. Finally, the staged setup combines both turbos to work together across the entire rev range. By optimizing the airflow admitted into the engine over a wider rev range, the bi-turbo system delivers top-tier performance, increased flexibility, and better fuel efficiency compared to a naturally aspirated engine of equivalent displacement.
Benefits
- ✓Significant increase in power and torque
- ✓Notable reduction in response time (turbo lag)
- ✓Broader and more consistent power and torque band
- ✓Improved flexibility and driving enjoyment
Learn more
Bi-turbo: dual turbocharging in the service of performance
In the world of automotive technologies aimed at optimizing the performance of internal combustion engines, the bi-turbo system, or "twin-turbo," holds a prominent place. It is a sophisticated evolution of the traditional turbocharger, which involves using not one, but two turbos to force-feed the engine. This approach pushes the limits of power and torque while addressing one of the main drawbacks of forced induction: turbo lag.
How does a Bi-turbo system work?
The basic principle remains the same as that of a single turbo: using exhaust gas energy to drive a turbine, which in turn operates a compressor to force more air into the cylinders. More air means better combustion and therefore more power. However, using two turbos allows for various configurations, each with its own advantages.
- Parallel twin-turbo: This is the most common configuration on V engines (V6, V8, V12). Each cylinder bank has its own identical turbocharger. This solution allows for smaller, more responsive turbos than a single large turbo, thereby reducing inertia and response time.
- Sequential twin-turbo: This configuration, often used on inline engines, employs two turbos of different sizes. At low revs, only the small turbo—which is lighter and quicker to spool up—operates. It provides immediate torque and eliminates "turbo lag." As engine speed increases, a bypass valve redirects the exhaust gases to the larger turbo, which takes over to deliver maximum power at high RPM.
- Staged twin-turbo: Similar to the sequential setup, this system operates both turbos (often of different sizes) in a complementary manner across the entire rpm range. The small turbo ensures pressure at low revs, then the large turbo kicks in to provide an additional volume of air, with both being able to work in tandem for maximum boost pressure.
The tangible benefits of Bi-turbo technology
The adoption of a bi-turbo system translates into several tangible benefits for the driver, explaining its popularity on sports and high-end vehicles.
- Increased power and torque: This is the most obvious advantage. Two turbos can deliver a much greater volume of compressed air than a single one, allowing the engine to develop power and torque worthy of a much larger displacement.
- Reduced response time: By using smaller turbos (in parallel) or a small turbo dedicated to low revs (in sequential), the bi-turbo system minimizes the famous "turbo lag." Throttle response is more instantaneous, offering increased driving pleasure and responsiveness.
- Extended power band: Particularly with a sequential configuration, the engine performs well across its entire operating range. It is torque-rich and responsive right from the lowest revs, while also capable of climbing in power explosively all the way to the redline.
- Downsizing optimization: The bi-turbo is a prime ally for engine downsizing. It enables the production of smaller-displacement engines offering performance levels equivalent to large naturally aspirated engines, with the advantage of better energy efficiency and reduced CO2 emissions under normal driving conditions.
Bi-turbo vs. Supercharger
It is important not to confuse the bi-turbo with the supercharger. While the turbo is driven by exhaust gases, the supercharger is directly driven by the engine via a belt. The supercharger offers instant response with zero lag, but it consumes some of the engine's power to operate. The bi-turbo, on the other hand, uses "free" energy (from the exhaust gases), generally making it more efficient, albeit more complex to implement.
In conclusion, bi-turbo technology is an advanced engineering solution that offers an exceptional compromise between raw power, responsiveness, and efficiency. It transforms an engine's character, making it both flexible for daily driving and formidably high-performing when the need arises.
Compatible brands
Finitions équipées
31 finition(s) proposent cet équipement
Porsche Porsche Cayenne
Cayenne GTS (3rd generation) (2020-2023)
Porsche Porsche Cayenne
Cayenne S (3rd generation) (2017-2023)
Porsche Porsche Cayenne
Cayenne S Diesel (2nd generation) (2012-2017)
Porsche Porsche Cayenne
Cayenne Turbo (2nd generation) (2010-2017)
Porsche Porsche Cayenne
Cayenne Turbo (3rd generation) (2018-2023)
Porsche Porsche Cayenne
Cayenne Turbo S (2nd generation) (2013-2017)
Porsche Porsche Macan
Macan GTS (1st generation) (2015-2021)
Porsche Porsche Macan
Macan S (1st generation phase 2) (2019-2024)
Porsche Porsche Macan
Macan S (1st generation) (2014-2021)
Porsche Porsche Macan
Macan S Diesel (1st generation) (2014-2018)
Porsche Porsche Macan
Macan Turbo (1st generation) (2014-2021)
Associated equipment
Diesel engine
The diesel engine, named after its inventor Rudolf Diesel, is a type of internal combustion engine whose operating principle is based on the auto-ignition of fuel. Unlike the gasoline engine, which requires a spark plug, the diesel engine compresses only air at a very high pressure (between 30 and 55 bar), which increases its temperature up to 700-900°C. Diesel fuel is then injected and finely atomized into the combustion chamber, where it spontaneously ignites upon contact with the superheated air. This rapid combustion creates a strong thrust on the piston, thereby generating motive power. Renowned for its high low-end torque and low fuel consumption, the diesel engine has long been the preferred choice for high-mileage drivers and commercial vehicles. Modern technologies, such as common rail direct injection, the turbocharger, and exhaust gas aftertreatment systems (Particulate Filter, SCR with AdBlue), have significantly improved its performance and efficiency while reducing pollutant emissions, making it more complex but also cleaner than ever.
Supercharger
The supercharger is a mechanical forced induction system designed to increase the power and torque of an internal combustion engine. Unlike a turbocharger, which uses exhaust gas energy, the supercharger is driven directly by the engine via a belt connected to the crankshaft. Its role is to compress the intake air before it enters the cylinders. By forcing a greater volume of air (and therefore oxygen) into the combustion chamber, the engine can burn more fuel, resulting in a more powerful explosion and a significant increase in performance. One of the main advantages of the supercharger is its instant response: because it is mechanically linked to engine speed, it provides immediate boost without the turbo lag sometimes associated with turbochargers. There are several types of superchargers, the most common being the Roots type, the twin-screw type, and the centrifugal type, each offering different performance and efficiency characteristics. This technology is particularly popular in sports cars and muscle cars for its ability to deliver linear and predictable power across the entire RPM range.
Gasoline engine
The gasoline engine, also known as a spark-ignition engine, is a type of internal combustion engine that has been the heart of the majority of light vehicles for over a century. Its operating principle is based on the four-stroke cycle: intake, compression, combustion-expansion, and exhaust. During this cycle, a mixture of air and fuel (gasoline) is drawn into a cylinder, compressed by a piston, and then ignited by an electric spark generated by a spark plug. The resulting explosion pushes the piston back down, creating the mechanical energy required to propel the vehicle. Modern gasoline engines have evolved considerably, incorporating advanced technologies such as direct injection, turbocharging (downsizing), or mild hybridization. These innovations aim to improve efficiency, increase power, and reduce fuel consumption as well as pollutant emissions. Appreciated for its flexibility, responsiveness, and rapid revving, the gasoline engine offers high driving pleasure, particularly suited for dynamic driving and urban trips.
Turbocharger
The turbocharger, commonly known as a 'turbo', is a forced induction system designed to increase the power and efficiency of an internal combustion engine. Its operating principle is based on utilizing the energy wasted in the exhaust gases. It consists of two main components mounted on a common shaft: a turbine and a compressor. The turbine, driven by the speed and pressure of the exhaust gases, spins the compressor. The compressor draws in ambient air, compresses it, and then sends it under pressure into the engine cylinders. By increasing the amount of intake air, the engine can burn a larger amount of fuel, thereby generating more power and torque for an equivalent displacement. This technology is at the heart of the 'downsizing' concept, which involves using smaller, turbocharged engines to achieve the performance of larger engines while reducing fuel consumption and CO2 emissions. Today, the turbocharger is ubiquitous in diesel engines and increasingly common in modern gasoline engines.
Direct injection
Direct injection is an engine technology where fuel is injected at very high pressure directly into the combustion chamber of each cylinder, rather than into the intake manifold as with indirect injection. This method allows for extremely precise control of the air-fuel mixture, both in terms of metering and injection timing. By spraying fuel directly into the cylinder, more efficient vaporization is achieved along with a cooling effect that increases the density of the intake air. This phenomenon allows for a higher compression ratio to be used without the risk of engine knock, resulting in more complete and efficient combustion. Initially popularized on diesel engines (with Common Rail technology), direct injection has become widely adopted in modern gasoline engines (GDI, FSI, THP, etc.) as part of downsizing strategies. It has become a technological pillar for manufacturers seeking to balance increasingly strict requirements regarding performance, fuel consumption, and pollutant emission reduction.