Belfast Audi More power from every drop of petrol Audi FSI technology

FSI technology increases the torque and output of petrol engines, making them up to 15% more economical and with reduced exhaust emissions. The dimensions and harmonisation of the combustion chamber design, combined with the airflow and injection rate, results in more power being squeezed out of every drop of fuel.

With FSI technology, fuel is injected directly into the combustion chamber. The injector regulates the amount of fuel with millisecond precision at injection pressures of between 30 and 110 bar. During the injection process, the evaporating fuel has a significant cooling effect on the cylinder charge. This contributes to improved cylinder charging and enhanced engine output. The cooling effect also helps reduce the engine’s tendency to knock. This reduction means that the compression ratio of FSI engines can be set considerably higher than for engines with conventional injection systems.

The engines of the FSI family are fitted with a two-stage variable intake manifold. The power mode (short duct length) contributes to the high specific power output of the engines at high engine speeds. At low revs, the long duct length setting is selected increasing the maximum torque by more than 15%.

With the aid of a flap system in the intake duct, the in-cylinder flow can be optimally adjusted. In part-load operation, a strong flow ensures low fuel consumption and low exhaust emissions. At full load, the air is drawn in with minimal losses, meaning that torque and output are increased.

Audi is the first manufacturer in the world to combine FSI technology with turbocharging in volume production. The exceptionally broad torque plateau of the TFSI engine on the one hand permits a fuel-efficient driving style with few gearshifts, and on the other hand means that only light accelerator action is needed to produce assertive thrust and a spontaneous unleashing of power.