Vanos and double-Vanos (double-variable camshaft control) improve the torque curve of an engine significantly. The special feature of both Vanos and double-Vanos is that they react to the engine speed and the position of the accelerator, adapting valve timing on both the intake and outlet camshafts by even the slightest quantities to suit the running conditions of the engine.
The result is even more torque at low speeds and superior performance at high revs. The reduction in unburnt residual gas improves the idling qualities of the engine, and special control maps for the warm-up phase enhance the efficiency of the catalytic converter. The car's Digital Motor Electronics (DME) are responsible for the fully-variable control of Vanos and double-Vanos.
