In the Japanese heavy duty truck market, demands of improved fuel economy and lighter vehicles to increase load capacity, and further improvements in emissions are constantly increasing.
To satisfy these requirements, basically a smaller sized and higher boosted diesel engine is effective, because such an engine has a compact size and light weight, and shows improved fuel consumption due to a relatively lower frictional loss.
On the basis of this concept Hino introduced the original EP100 in 1981 as the first Japanese turbocharged and air to air charge-cooled engine. Since then Hino has made many efforts to improve the engines and develop new technologies.
This paper describes some advanced technologies which includes the so-called multi harmonized (variable length) inertia charging system, the electronically controlled turbocharger waste gate valve and 4 valve system which have been developed in the engine from the EP100 to the EP100-I,II, the P09C and the latest P11C, to further improve the high boosted diesel engine and thus overcome some of the problems inherent in such an engine, thereby achieving its status as the state of art engine at Hino.