Mitsubishi's new clean diesel engines use a high-pressure common rail injection system to improve
combustion efficiency. The
4N13 uses
solenoid fuel-injectors. The larger
4N14 engine uses
piezo fuel-injectors that produce a finer fuel spray. Both engines feature a fast
ceramic glowplug system. The engines are designed to operate at a lower
compression ratio, thus lowering the combustion pressure, allowing the use of an aluminium cylinder block that reduces
weight. The
4N13 engine uses a variable geometry (VG) turbocharger with a variable vane
turbine, which provides optimal
boost pressure control for different driving conditions. The
4N14 engine also uses a VG turbocharger plus a variable diffuser (VD) that uses both variable geometry vanes in the turbine housing and a
compressor with variable vanes in the diffuser passage, further improving combustion efficiency. Within the engine, Mitsubishi used an offset angle
crankshaft that reduces friction, therefore noise and vibration, allowing the engine to run smoothly and quietly at all
engine speeds. To meet the requirements of global
emissions standards, Mitsubishi developed a new catalyst system that combines a
Diesel Oxidation Catalyst (DOC),
NOx Trap Catalyst (NTC) and
Diesel Particulate Filter (DPF). ==4N13==