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The needs of the non-internal combustion engine for the automobile have been increasingly emphasized due to the seriousness of the air pollution in major cities and the global warming. However, such power plant technologies are generally considered to be still far away from the full commercialization as technical issues including infrastructure and cost are still remaining to be solved, so the substantial emission cleanup through the market penetration requires a long time for the realization. For the mean time, attempts are made to investigate the maximum potential of the internal combustion engine for reduction of both exhaust emissions and CO2 focusing on Honda''s near-zero emission Zero Level Emission Vehicle (ZLEV) technology.

The College of Engineering-Center for Environmental Research and Technology at the University of California, Riverside and Honda Motor Company are conducting a cooperative research program to study the emission characteristics and evaluate the environmental impact of advanced technology vehicles designed to have emission rates at, or below, the California ULEV standard. This program involves a number of technical challenges relating to instrumentation capable of measuring emissions at these low levels and utilizing this instrumentation to gather data under realistic conditions that will allow assessments of the environmental impact of these advanced vehicle technologies. This paper presents results on the performance and suitability of a Fourier Transform Infrared (FTIR) based on-board measurement system developed principally by Honda R&D for this task. This system has been designed to simultaneously measure vehicle exhaust and ambient roadway pollutant concentrations.

ZLEV was accomplished by applying the Three-Stage Emission Management System, utilizing ultra-precise combustion and exhaust gas conversion control technology, and dividing the operation into three-stages of just after engine start, the warm-up stage, and normal running. These individual component technologies include improving engine combustion (high swirl combustion by variable valve timing and lift) and performing fuel control optimization during engine startup to reduce unburned HC emission, quick catalyst activation (engine control and catalyst improvements), HC adsorption of a hybrid catalyst (catalyst improvement and desorption conversion control), and high precision air-fuel ratio feed back control (catalyst condition predictive control, and others).

A new simple ULEV system has been developed, using only an underfloor catalytic converter. The new system features a VTEC (variable valve timing and lift mechanism) engine with a newly developed catalyst, a precise air-fuel ratio control for maximizing the catalyst performance and the newly developed low heat capacity exhaust system with the air-gap. These technology have contributed to a reduction in the feed gas, the quick activation of the catalyst and an improvement in the maximum conversion ratio of the catalyst, making it possible to pass the ULEV standard without sacrificing vehicle output power.

With the total amount of air pollution caused by vehicle emissions on the increase, the problem has now became a global concern, and various regulatory measures have been put into effect in each region of the world. This is especially true in California, U.S.A, where countermeasures have been adopted early. There, the ULEV (Ultra Low Emission Vehicle) standard, which was ones deemed impossible for gasoline engines to meet, is now in effect. In response to these developments, Honda announced the ULEV system for a 2.2 liter gasoline engine with a closed-coupled catalytic converter (CC) and an under-floor catalytic converter (UF) at the beginning of 1995, and reported on the system's emission characteristics. 1) A new ULEV system has been developed based on the previous system but using only UF, aiming for marketable improvements in product characteristics such as higher output. The new system features the ultra low heat capacity and high heat insulating (ULOC) exhaust manifold.

A turbocharger which has four pairs of fixed vanes and movable vanes inside the turbine scroll was developed. A 1.2-liter experimental gasoline engine with this turbocharger was made and mounted in the body of a passenger car. This variable-geometry mechanism did not need a waste-gate system. Results of bench tests showed that this engine generated a 93.3 kPa (700 mmHg) boost pressure over a 6,000 rpm range. This paper presents the mechanism, operation, and performance data of this variable-geometry turbocharger, as well as the performance data of the 1.2-liter experimental engine and this passenger car.

A variable valving system was developed. This system has two cam profiles, one for low speed and one for high speed. A 1.2-litre DOHC experimental engine using this system was made and mounted in the body of a 2-1itre class passenger car. Test results of this car were compared to those of the same car with its original engine. The test car showed better results in every area of driving performance, in mode-fuel-econorny and in noise tests. This paper presents the mechanism, operation and test results of this variable valving system, the 1.2-litre experimental engine and this passenger car. THE PERFORMANCE AND EFFICIENCY of the passenger car gasoline engine have been greatly improved: primarily as a response to exhaust-gas emission regulations and the oil crises. These improvements have been achieved mainly through the development of control technologies to optimize many parameters such as ignition timing and air fuel ratio precisely according to driving conditions.