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A 1.8L Gasoline Direct Injection Compression Ignition (GDCI) engine was tested over a wide range of engine speeds and loads using RON91 gasoline. The engine was operated with a new partially premixed combustion process without combustion mode switching. Injection parameters were used to control mixture stratification and combustion phasing using a multiple-late injection strategy with GDi-like injection pressures. At idle and low loads, rebreathing of hot exhaust gases provided stable compression ignition with very low engine-out NOx and PM emissions. Rebreathing enabled reduced boost pressure, while increasing exhaust temperatures greatly. Hydrocarbon and carbon monoxide emissions after the oxidation catalyst were very low. Brake specific fuel consumption (BSFC) of 267 g/kWh was measured at the 2000 rpm-2bar BMEP global test point.

In this paper, a comparative study of the production applications of hybrid electric powertrains is presented. Vehicles studied include the Toyota Prius, Honda Insight, Toyota Estima, Toyota Crown, Honda Civic Hybrid, and Nissan Tino. The upcoming Ford Escape Hybrid and General Motors Parallel Hybrid Truck (PHT) will also be included, although advance information is limited. The goal of this paper is to look at what hybrid drivetrain architectures have actually been selected for production and what are the underlying details of these drivetrains. Since hybridizing a powertrain involves significant changes, the powertrain architectures are presented in diagram form, with analysis as to the similarities and advantages represented in these architectures. The specific hybrid functions used to save fuel are discussed. Peak power-to-weight ratio and degree of hybridization are plotted for the vehicles. System voltage versus electric power level are also plotted and analyzed.

Previous studies of gasoline direct-injection compression-ignition (GDCI) showed good potential for very high efficiency, low NOx, and low PM over the full speed-load range. Low-temperature combustion was achieved using multiple-late injection (MLI), intake boost, and cooled EGR. Advanced injection and valvetrain were key enablers. In the current study, a new piston was developed and matched with the injection system. Single-cylinder engine tests were conducted with the objective to reduce injection pressure, intake boost, and swirl levels. Results showed that ISFC could be further improved while maintaining low levels of NOx, PM, and combustion noise. Efficiency loss analysis indicated a very efficient thermodynamic process with greatly reduced heat losses. Injection parameters could be used to control combustion phasing with good combustion stability. Engine simulations were performed to develop a practical boost system for GDCI.