Simultaneous attainment of low fuel consumption high output power and low exhaust emissions in direct injection SI engines

Yasuo Takagi, Teruyuki Itoh, Shigeo Muranaka, Akihiro Iiyama, Yasunori Iwakiri, Tomonori Urushihara, Ken Naitoh

Research output: Contribution to journalConference article

68 Citations (Scopus)


This paper describes simultaneous attainment in improving fuel consumption, output power and reducing HC emissions with a direct injection S.I. engine newly developed in Nissan. Straight intake port is adopted to increase discharge coefficient under WOT operation and horizontal swirl flow is generated by a swirl control valve to provide stable stratified charge combustion under part load conditions. As a result, fuel consumption is reduced by more than 20% and power output is improved by approximately 10%. Moreover, unburned HC is reduced by equivalently 30% in engine cold start condition. An application of diagnostic and numerical simulation tools to investigate and optimize various factors are also introduced.

Original languageEnglish
JournalSAE Technical Papers
Publication statusPublished - 1998 Jan 1
Event1998 SAE International Congress and Exposition - Detroit, MI, United States
Duration: 1998 Feb 231998 Feb 26


ASJC Scopus subject areas

  • Automotive Engineering
  • Safety, Risk, Reliability and Quality
  • Pollution
  • Industrial and Manufacturing Engineering

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