Fuel Stratified Injection (FSI)
Fuel Stratified Injection (FSI) technology — the future of spark-ignition technology that delivers more torque and power, and is more dynamic and efficient than engines with conventional indirect injection. What’s more, it reduces fuel consumption by up to 15 per cent.
FSI is the state-of-the-art in fuel injection technology available now on top petrol engine. It increases both torque and power while improving economy and reducing exhaust emissions.
As opposed to standard manifold injection systems, FSI engines inject fuel directly into the cylinder and use a specially shaped piston crown to concentrate the air/fuel mix below the sparkplug. This produces optimal fuel combustion, which in turn, reduces heat loss and increases output while minimising fuel consumption and emissions. FSI technology has been hailed as the most significant step forward for the petrol engine since fuel injection itself replaced the carburettor.
Most engines work on the principle that an even — or ‘homogeneous’ — mixture of fuel and air, at the correct proportion, is the ideal for combustion. And so it is, especially if full power is required, for example when accelerating. But how much of the time are we accelerating? What happens under a trailing throttle, for example when slowing for a junction or holding station in traffic? Audi’s engineers discovered that under those conditions having a homogeneous fuel-air mixture could be wasting energy, and thus fuel. At such times the FSI engine switches to something called a ‘stratified’ charge, where the injector releases a precisely-timed and directed smaller charge of fuel, creating a variable mixture of fuel and air that is at its richest around the spark plug, for instantaneous combustion, but that becomes leaner further away from the spark. Enough power for the situation, a clean and highly efficient burn. In simple terms, this means that the driver has all the power he or she needs, whenever it is needed, but that the engine smoothly and seamlessly switches to a leaner burn mode whenever the car is in a steady-state cruise or is decelerating.
Direct Shift Gearbox (DSG)
It’s not only the visible aspects of the Altea that are revolutionary; the Direct Shift Gearbox (DSG) breaks completely new ground in gearbox design and technology. It offers a real alternative to drivers preferring a sportier, manual gearbox as it delivers all the agility and rapid, crisp changes they’re used to, while providing the comfort and smoothness of an automatic. The revolutionary DSG combines the advantages of a conventional 6-speed manual gearbox with the qualities of a modern automatic transmission. This is combined with good economy thanks to low fuel consumption, and convenient operation. The basis for this new development is a three-shaft 6-speed manual gearbox, which offers considerable variability in the selection of the transmission ratios. Thanks to the use of a double multi-plate clutch with an ingenious electro-hydraulic control system, two gears can remain engaged at the same time. Apart from its high efficiency and the ability to transmit high torque, the big advantage of this special kind of clutch is the various options it offers the driver when setting off. The driver is able to control the multi-plate clutch as he desires, varying from a particularly gentle acceleration process on slippery ground all the way to sporting, full-power acceleration, and with countless variants in between.