Patent ID: 7395668

Claim:
A method for controlling a diesel-type piston engine comprising at least one combustion chamber formed by a cylinder ( 52 ) and a movably arranged piston ( 53 ) in each cylinder that is connected to a crankshaft ( 54 ), an injection device ( 56 ) configured to inject fuel directly into the combustion chamber, and a turbo system comprising a low-pressure turbo ( 22 ) and a high-pressure turbo ( 18 ) disposed downstream of the low-pressure turbo ( 22 ), the low-pressure turbo ( 22 ) and high-pressure turbo ( 18 ) each having a turbo map efficiency greater than 60%, the method comprising utilizing a control mechanism for gas exchange valves ( 57 , 58 ) to establish at least a first operating range for the internal combustion engine at a mean piston velocity greater than 6 m/s and at an engine load greater than 15 bar BMEP at which the volumetric efficiency within said first operating range is less than 70%.