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The hydrogen fueled engine with direct injection and spark ignition system, which had normal combustion for a wide range of air/fuel equivalence ratio, was developed by using hydrogen gas injection valve with a Teflon insert on its valve seat and determining optimum injection hole configuration and injection timing. Performance characteristics of the hydrogen fueled engine with respect to several variables such as spark timing, air/fuel equivalence ratio, and engine speed were analyzed and compared with those of gasoline engine. It was found that qualitative trend of the engine performance of engines was similar while quantitative characteristics as to spark timing, torque, and cyclic variation of hydrogen fueled engine were different from those of gasoline engine.

In order to realize lean burn engine by improving the ignitability of ignition system, the possibility about the adaptability of the Multi Spark Capacitor Discharge Igniter (MSCDI) was analyzed. The MSCDI had an effect on the increase of the ignition energy and discharge period, and it was excellent in high speed without noise. The result of engine test with the MSCDI shown about 10% extension of lean limit, and 5% increase of brake thermal efficiency than the ignition system with single spark ignition apparatus. And the coefficient of cycle variation in the IMEP was remarkably decreased.