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: exhaust turbocharger with charging-pressure control turbocharger with ball bearing and variable vane geometry MAN direct injection with bowl-in piston carburetter test