The turbocharger in the Cayenne Diesel features Variable Turbine Geometry (VTG). The gas-flow from the engine is channelled onto the turbines via electronically adjustable guide vanes. By changing the vane angle, the system can replicate the geometry in all types of turbo, large or small, and thus achieve the optimum gas-flow characteristics. As a result, even at low engine rpm, the turbine speed is maximised. For a significant increase in boost pressure, excellent cylinder charging plus greater power and torque.