VTG Turbochargers

VTG Turbochargers

Like its predecessor, the 911 Turbo DFI features turbocharging with variable turbine geometry (VTG). The new 911 Turbo therefore once again demonstrates the core competence of Porsche in engine technology and continues to set standards amongst the current competition. Use of this turbocharging technology is exceptional for turbocharged spark-ignition engines. Featuring variable turbine blades, it enables the new 911 Turbo to operate with a maximum exhaust temperature of up to approx. 1832 °F. (1000 °C)

In order to adapt to the higher performance figures, the turbochargers for the new 911 Turbo have improved flow properties and the compressor wheel has been enlarged. The diverter valves, which relieve excessive pressure when the throttle valve is closed quickly, have also been modified. In the previous model, they were integrated in the turbochargers. The diverter valves in the new 911 Turbo are located immediately upstream of the throttle valve. This position allows improved flow behaviour in the exhaust system.







The DME control unit regulates the boost pressure by activating the respective electric boost pressure adjuster (EL) on the VTG turbocharger. This then changes the position of the turbine blades by means of the adjusting ring (VR). The principle of variable guide blades, which guide the exhaust flow onto the turbine wheels of the turbocharger in a variable and targeted manner, combines the function of small and large turbochargers in the new 911 Turbo as well. With almost closed guide blades for good response with high torque values at low rpm and open guide blades for high output values at high rpm. In addition, maximum torque is available over a wide engine speed range.







As in the previous model, the bearing housings of the turbochargers in the new 911 Turbo are also cooled with water. An electric auxiliary water pump increases water throughput at low engine speeds to meet the cooling requirement. It also permits efficient cooling of the highly loaded turbochargers even when the engine is stopped after the vehicle has been driven with high power demands (after-run cooling).