Brief description
Brief description |
Description |
Unlike a conventional aspirating engine, a supercharged engine has improved filling during the induction stroke, which means more efficient combustion, higher power, higher torque and lower fuel consumption. This all adds up to a performance comparable with a larger engine, while retaining the advantages of a smaller one with regard to fuel economy, space, weight, etc.
Supercharging is done using a turbocharger, which uses the engine exhaust gas to drive it. Exhaust gas is led into a turbine housing with variable vanes (VNT, Variable Nozzle Turbine).
The engine exhaust makes a turbine wheel rotate. The turbine wheel is in direct contact with a compressor impeller, which means the compressor impeller rotates at the same speed as the turbine wheel. The compressor impeller increases the pressure in the induction system, which means more air is entering the engine. This makes it possible to burn more fuel, resulting in higher torque and power. The engine control module regulates this process by checking the position of the vanes, amongst other things.
The vane opening is adapted for a particular running condition, usually with a small opening for low engine loads. For high engine loads, the vanes will open up to regulate the turbine speed and thereby also the degree of supercharging.
The turbo is designed to start working even at relatively low engine speeds, which gives the engine a high torque in speed ranges that are used in normal driving conditions. The high torque and short turbo delay make the car smooth and comfortable to drive.
The turbocharger turbine housing is integrated in one unit with the engine exhaust manifold.