two-stage turbocharger (bi-turbo) Cutaway are: both turbochargers, control flaps and the fresh-air valve. The turbines and throttle valves can be moved. Exhaust air, fresh air and oil channels are accentuated in colour. description ordernumber 1327 see also: Demand-driven oil pump without suction stage (V6) Common-rail high pressure pump with fuel-delivery regulation valve pump with slide-valve control (electronically controlled) actuator for cruise control