What does Audi AVS system mean?
The common VVT variable valve timing system can only adjust the opening time of intake valve or intake and exhaust valve; Audi AVS system, like Honda i-VTEC system, can further control the opening lift of intake valve. The mechanical structure of Audi AVS variable valve lift system is slightly different from Honda i-VTEC: there are two groups of cams with different angles on the camshaft to control the intake valve, and a spiral groove sleeve is responsible for changing the lift. The spiral groove sleeve is controlled by an electromagnetic driver, and two groups of different cams are switched to change the opening lift of the intake valve.
Under the condition of high engine load, the AVS system moves to push the cam 7 mm to the right, so that the cam with larger angle pushes the valve ejector rod; In this case, the valve lift can reach 1 1mm, thus providing the best intake flow rate and intake flow rate of the combustion chamber and achieving stronger power output.
In the case of low engine load, in order to pursue the fuel-saving performance of the engine, AVS system pushes the cam to the left and pushes the valve ejector rod with a smaller cam. At this time, the valve lift can be adjusted between 2 mm and 5.7 mm. Due to the asymmetric intake lift design, air enters the combustion chamber in a spiral manner. The design of combustion chamber and piston head with special profile can further optimize the oil-gas mixing state in the cylinder. Audi AVS variable valve lift system can work between 700-4000 rpm, and the biggest advantage of AVS system is that it can reduce fuel consumption by 7%. Especially when cruising at a constant speed in the middle speed range, the fuel saving effect of AVS system is the most obvious.