Abstract
Honda has developed new "i-DSI"(Intelligent-Dual and Sequential Ignition) gasoline engine with the aim of achieving high fuel economy, reducing exhaust emissions, and having a wide cabin space by being lightweight and compact design for small category vehicles. This paper describes the characteristic methods of new "i-DSI" engine. At first, the engine has dual sparkplugs which are located at the diagonal position in order to conduct the flame shortly, and which control the ignition on consequential phase to burn rapidly throughout the all driving conditions. The higher compression ratio of 10.8 was materialized by the compact combustion chamber with a narrow valve angle, the improvement of in-cylinder flow. In addition to the high compression ratio, the modification of valve timing and lift, the enlargement of valve diameter, the improvement of the air intake and exhaust systems were achieved to increase the power output. Furthermore, the new technologies for reduction of the friction loss were applied to this engine. One of the most characteristics is the shot peening with molybdenum disulfide at the face of piston skirt. Also, 6-hole-injector, EGR system, and oblique structuring exhaust converter are adopted to reduce the emissions. By having those characteristic methods, the engine has improved by 27% in power and by 15% in fuel economy over the previous model.