More power and torque with less fuel consumption – that is the dream of every engine designer. With the Audi valvelift system, which manages the inlet valve timing in a gasoline engine in a very innovative way, that dream becomes a reality. Audi uses this technology for its direct-injection 2.8 and 3.2-liter V6-FSI engines in the A4, A5, A6 and A8.
Intelligence is all in the head, one might say – the cylinder head in the case of a car’s engine. The aim is to open and close the valves in such a way that the correct charge of air is always drawn into the cylinders. The first breakthrough came years ago with the rotation of the camshaft by means of adjusters – permitting the valve opening and closing times to be varied. The Audi valvelift system now achieves the next step – variable control of the valve lift, thus influencing the cross-section of the intake duct.
How it works: The two inlet camshafts are equipped with teeth. On each of them sit three cam elements – cylindrical sleeves, on the outside of which there are spiral grooves. There are six metal pins integrated into the ladder frames of each of the two cylinder heads, which extend by four millimeters, powered by lightning-fast electromagnetic actuators. Two of them are responsible for each cam element.