A New 3-Cylinder 1.0L Engine Development for Light Weight and Good Fuel Economy

Authors

T. Nara, T. Kusunoki, N. Sugita, Toyota Motor Corporation, Aichi-ken, Japan; E. Mishima, Daihatsu Motor Company LTD., Osaka, Japan

Year

2005

Print Info

Fortschritt-Berichte VDI, Reihe 12, Nr. 595

Summary

In order to meet the requirement for CO2 emission reduction, Toyota and Daihatsu have jointly developed the 1KR-FE new 3-cylinder 1.0L gasoline engine. Beside excellent fuel economy, the development targets for this new engine were; top of class performance, lightweight and compactness. In addition to friction reduction obtained by using only 3 cylin-ders instead of 4, benefits were gained by using thin piston rings with low tension. Also a new type of resin coat on the piston skirt contributes to lower friction. The result is 109g/km of CO2 for the new Toyota Aygo. Thanks to optimisation of combustion chamber design and the introduction of VVT-i, a maximum power output of 50kW and a maximum torque of 93Nm were achieved. Also a low-speed torque of 85Nm is already available at 2000rpm. All intake air system components are made in plastic to reduce engine weight and to make a highly integrated packaging possible. A newly developed cast iron liner with small wall thick-ness allows only 7 mm spacing between cylinder bores leading to the compactness of the engine. To reduce the vibration level, moving parts weight was reduced, rigidity of cylinder block was increased and a crankshaft with 3 counter weights was developed. Improved engine mountings combined with a torque rod system minimise idle speed vibration.

Order Members Login