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Delphi has developed a Continuously Variable Valve Lift [CVVL] mechanism to improve spark ignition engine part throttle fuel economy through the minimization of pumping losses and reduction of cam drive torque. The latest CVVL design is focused on meeting valve lift duration targets derived from combustion analysis at key speed and load points, reducing packaging envelope, and reducing part count for low cost. Delphi's CVVL design process, simulation used to predict performance, and hardware confirmation testing will be presented and discussed in this paper.

LEV-3 regulation changes require 100% SULEV30 fleet average by 2025. While present applications meeting SULEV30 are predominately small displacement 4-cylinder engines, LEV-3 standards will require larger displacement engines to also meet SULEV30. One concept previously investigated to reduce the cold start engine-out HC emissions was to heat the fuel injected during the cold start and initial engine idle period. Improved atomization and increased vaporization of heated fuel decreased wall wetting and unburned fuel. This resulted in more fuel available to take part in combustion, thus reducing the required injected fuel mass and HC emissions. Single cylinder engine testing with experimental heated Gasoline Direct Injection (GDi) injectors was conducted at 40°C engine coolant and oil temperature conditions. The operating mode simulated cold start idle operating conditions, with split injection for improved Catalyst Light-Off (CATLO) times.