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This paper describes important aspects of the development process for meeting CARB's “Ultra-Low” 3-Star emissions with engines using the new E-TEC™ direct injection system. In-house research and analysis of data from other state-of the-art engines were used to determine achievable emission levels and to set the development targets. A detailed mode-point-specific analysis of the emissions potential of the FICHT® direct injection system revealed excellent system capability in homogeneous operation and limited potential for stratified operation. Based on these results, the development work was focused on the reduction of stratified hydrocarbon emissions. Wall impingement of the fuel spray onto the piston surface was identified as a major source of hydrocarbon emissions during stratified operation. A zero-dimensional simulation of various parameters affecting wall impingement indicates that droplet size, in-cylinder temperature, and penetration velocity are the three major factors.