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This paper reports on DaimlerChrysler's participation in the Ad Hoc Diesel Fuels Test Program. This program was initiated by the U.S. Department of Energy and included major U.S. auto makers, major U.S. oil companies, and the Department of Energy. The purpose of this program was to identify diesel fuels and fuel properties that could facilitate the successful use of compression ignition engines in passenger cars and light-duty trucks in the United States at Tier 2 and LEV II tailpipe emissions standards. This portion of the program focused on minimizing engine-out particulates and NOx by using selected fuels, (not a matrix of fuel properties,) in steady state dynamometer tests on a modern, direct injection, common rail diesel engine.

Glass fiber reinforced plastic of polyamide is applied as one of the materials used for the high strength exterior parts of a motorcycle, such as a rear grab rail or a carrier, to which both strength and good exterior appearance are required. However, Glass Fiber reinforced Polypropylene (PPGF), which is relatively inexpensive material, has a property that the contained glass fibers are prone to be exposed at the surface and, therefore, the requirements for good appearance are hardly met by using PPGF. In this study, Heat and Cool molding method (H&C molding) was employed to realize a cost reduction by using PPGF yet without applying painting process, and the established method was applied to mass production while fulfilling the requirements for a good exterior appearance. In H&C molding, the metal molds are heated up by steam and cooled down by water after molding.

The atomization of molten aluminum when injected during high-pressure die casting is analyzed to determine its effect in enhancing the strength of the product being cast. In the previously reported first step of this study, molten aluminum was injected into open space and its atomization was observed photographically. Now in the second step of the study, a simulation is conducted to determine how the molten aluminum becomes atomized at the injection nozzle (gate) and how this atomized material flows and fills the cavity. A new simulation method is developed based on large-eddy simulation coupled with the volume-of-fluid method. The simulation system is verified by comparing its output with photographs taken in the first step of the study. Simulations are then conducted using an approximation of a real cavity to visualize how it is filled by the atomized molten aluminum.

High-tensile steel plates and lightweight aluminum are being employed as materials in order to achieve weight savings in automotive subframe. Closed-section structures are also in general use today in order to efficiently increase parts stiffness in comparison to open sections. Aluminum hollow-cast subframe have also been brought into practical use. Hollow-cast subframe are manufactured using sand cores in gravity die casting (GDC) or low-pressure die casting (LPDC) processes. Using these manufacturing methods, it is difficult to reduce product thickness, and the limitations of the methods therefore make the achievement of weight reductions a challenge. The research discussed in this paper developed a lightweight, hollow subframe technology employing high-pressure die casting (HPDC), a method well-suited to reducing wall thickness, as the manufacturing method. Hollow-casting using HPDC was developed as a method of forming water jackets for water-cooled automotive engines.

There are a couple of ways to manufacture aluminum cylinder blocks that have a good balance between productivity and abrasion resistance. One of them is the insert-molding of a sleeve made of PMC (Powder Metal Composite) by the HPDC (High Pressure Die Casting) method. However, in this method, cracks are apt to occur on the surface when the PMC sleeve is extruded and that has been a restriction factor against higher extrusion speed. The authors attempted to raise this extrusion temperature by eliminating the Cu additive process from the aluminum alloy powder in order to raise its melting point by approximately 50 °C. This enabled the wall of the extruded sleeve to be thinner and the extrusion speed to be higher compared to those of a conventional production method while avoiding the occurrence of surface cracks.

There are several all-aluminum cylinder blocks. A typical example is a mono-block cylinder of alusil alloy produced by low pressure die casting. This material's resistance to abrasion and seizure, however, is not satisfactory for motorcycle; in addition, long processing time is another disadvantage. To cope with these problems, the authors developed a light and highly productive all-aluminum cylinder block with a cast-in liner through die casting. The liner is made from powder metallurgy composite (PMC) with 3 to 5 % alumina and 0.5 to 3 % of graphite additives. The PMC reconciles abrasion resistance and machinability. The hardness deterioration of the composite due to the heat at die casting is avoided by using heat-resistant rapidly-solidified powders, made from an aluminum-silecon-iron alloy, for the matrix.

In general, welding of high-pressure die casting (DC) parts has been difficult due to gases trapped in the castings. This is a result of the high-speed turbulent flow condition of the DC process. These gases are liberated during welding and produce porosity in the weld joint. The Author had found the range where an enough welding quality was obtained without great drop in castability to the middle of the laminar flow and turbulent flow. This range has been defined as the transition zone. Moreover high strength Al-Mg-Ni alloy was developed by non-heat-treatment. The Transition Flow Filling Method(TFFM) has been developed, that can not only reduce the amount of trapped gases but also is applicable to standard high pressure die casting equipment. With this method, high quality DC parts can be produced that are weldable, strong and have high toughness.

Into the early-part of the next century, automotive emission standards are becoming stricter around the world. The electrically-heated catalyst (EHC) is well known as an effective technology for the reduction of cold-start hydrocarbon emissions without a significant increase in back pressure. Our extruded, alternator powered EHC (APEHC) manufactured with a unique canning method and equipped with a reliable, water proof electrode has demonstrated excellent durability and reliability, as stated in our previous SAE paper (#960340). The APEHC system discussed in this paper has achieved the Ultra-Low-Emission Vehicle (ULEV) standards, after 100,000 miles of fleet testing, without any failure. This is the final milestone in addressing the EHC as a realistic-production technology for ULEV. With the ability to meet ULEV/Stage III emission targets without a significant increase in back pressure, the EHC will be applied to an especially high performance vehicle with a large displacement engine.

The new die cast (HPDC) wheel alloy has been developed using recycled aluminum to attain considerable reduction of energy at the time of material production to make large contribution to the reduction of CO2 emissions. The material for motorcycle body parts, especially for wheels, requires a sufficient elongation property. However, when recycled aluminum, which contains large amount of impurities, is used as main raw material, the intermetallic compounds crystalize out and the elongation property is deteriorated. Accordingly, we firstly made the investigations on the elements contained in a recycled aluminum and it was clarified that the elongation property was correlated to the shape of crystallized iron-based intermetallic compounds.

The technology for a new, high-strength piston material has been developed by using high pressure die casting (HPDC) method, which had a rapid rate of solidification. This method allowed the amount of Ni added to be increased to 5.5 mass%, raising the fatigue strength of the new material at temperatures of 523 K or higher by a factor of 1.5 over that of a conventional material made by gravity die casting (GDC). In addition, application of vacuum to the die cavity and using additional pressure enabled quality exceeding that of conventional GDC pistons. Pistons made from the newly developed material decreased engine friction by 4.4% and increased fuel efficiency by 2.2% in engine bench testing.

Using sand cores, the weld-able, hollow die-cast parts have been developed. For casting, the transition flow filling method is applied to reduce gas containment and to minimize damages to the core. In designing the products, the newly developed core stress prediction system by melt pressure distribution and the newly developed in-product gas containment prediction system have been applied. The hollow die-cast frame made by the new method attains a 30% increase in rigidity and 1kg reduction of weight.

This research is aimed at development of the catalyst for gasoline automobiles which uses only palladium (Pd) among platinum group metals (PGMs). And the conformity emission category aimed at LEV III-SULEV30. For evaluation, the improvement effect was verified for 2013 model year (MY) ACCORD (LEV II-SULEV) as the reference. As compared with Pd-rhodium (Rh) catalyst, a Pd-only catalyst had the low purification performance of nitrogen oxides (NOx), and there was a problem in the drop in dispersion of Pd by sintering, and phosphorus (P) poisoning.

Aiming for higher output power, greater fuel economy and reduced exhaust emissions, a new V-6 3.5-liter i-VTEC Variable Cylinder Management (VCM) engine has been developed. This engine uses a cylinder-deactivation mechanism with VTEC technology that allows the number of cylinders to be controlled in three modes (three, four or all six cylinders), according to the operating conditions. This adds a four-cylinder mode to the conventional cylinder- deactivation engine. In addition to increasing the number of cylinder- deactivation modes, the new hydraulic circuits, a hydraulic pressure switching mechanism and a switchover control were also developed. These make it possible to instantaneously switch the active cylinders without impairing drivability, in the same manner as a conventional engine.

In order to contribute to the resolution of global environmental problems and to respond to the issue of diminishing resources, the Civic Hybrid, a hybrid passenger automobile has been developed to achieve both low emissions and low fuel consumption. The hybrid system takes the conventional Honda IMA (Integrated Motor Assist) system as its foundation. 4-cylinder, 1.3L SOHC, 2-plug engine i-DSI (DSI: Dual and Sequential Ignition) has been selected and modified for lean burn combustion. In addition, a cylinder idling system to increase the amount of electrical energy regenerated during deceleration has been adopted, among other technology. The ultra-thin DC brushless motor has been modified with its magnetic circuit to improve maximum regenerative torque by approximately 30%. Thanks to a new power train that improves CVT transfer efficiency, low fuel consumption of 48mpg in the city and 47mpg on the highway (the 5MT vehicle is 46mpg in the city and 51mpg on the highway) is achieved.

With the increasing number of automobiles, the worldwide problem of air pollution is becoming more serious. The necessity of reducing tail-pipe emissions is as high as ever, and in countries all over the world the regulations are becoming stricter. The emissions at times such as after engine cold start, when the three-way catalyst (TWC) has not warmed up, accounts for the majority of the emissions of these pollutants from vehicles. This is caused by the characteristic of the TWC that if a specific temperature is not exceeded, TWC cannot purify the emissions. In other words, if the catalyst could be warmed up at an early stage after engine start, this would provide a major contribution to reducing the emissions. Therefore, this research is focused on the substrate weight and investigated carrying out major weight reduction by making the porosity of the substrate larger than that of conventional products.

Recently, automotive emission regulations are being further tightened, such as the Tier III/LEV III in the U.S. As a result, reducing cost of after-treatment systems to meet these strict regulations has become an urgent issue, and then the demand for high-precision air-fuel ratio (A/F) control which can achieve this cost reduction is high [1]. On the other hand, in order to meet rapidly changing market needs, it is becoming difficult to keep enough development periods that enable sufficient calibration by trial-and-error, such as feedback-gain calibration. This leads to an increase in three-way catalytic converter costs in some cases. For these reasons, it is necessary to construct control system that can make full use of hardware capabilities, can shorten development periods regardless of the skill level of engineers.

Measuring the real-world performance of emission control technologies is an important aspect in the development of advanced low-emission vehicles. In addition, data acquired from such measurements can be used to improve the accuracy of air quality predictive models. Honda has developed an on-board sampling/analysis system capable of measuring on-road emissions at ULEV levels and below. Ambient air can be analyzed simultaneously. This FTIR-based system can measure several species; this paper will focus on NMHC, NOX, and CO. Techniques were developed to address the challenges associated with acquiring accurate real-time data at concentrations below 1 ppm in an on-road vehicle. Validation studies performed with reference gases and vehicle exhaust indicate a very good correlation between the on-road analyzer system and classic bench methods for all target compounds. Dynamic studies performed by the University of California, Riverside, also show good correlation.

The Automotive Industry/Government Emissions Research CRADA (AIGER) has been working to develop a new methodology for the direct determination of nonmethane hydrocarbons (DNMHC) in vehicle testing. This new measurement technique avoids the need for subtraction of a separately determined methane value from the total hydrocarbon measurement as is presently required by the Code of Federal Regulations. This paper will cover the historical aspects of the development program, which was initiated in 1993 and concluded in 2002. A fast, gas chromatographic (GC) column technology was selected and developed for the measurement of the nonmethane hydrocarbons directly, without any interference or correction being caused by the co-presence of sample methane. This new methodology chromatographically separates the methane from the nonmethane hydrocarbons, and then measures both the methane and the backflushed, total nonmethane hydrocarbons using standard flame ionization detection (FID).

The two liter DOHC-VTEC engine developed for the Honda S2000 produces 179kW (240HP, which is 120HP per liter). It is the highest output power among all naturally aspirated two liter engines ever mass-produced. It also achieves an exhaust emission level within National LEV standards. The new engine utilizes a redesigned VTEC cylinder head, in which MIM (metal injection molding) rocker arms are used. The new cylinder block with a ladder frame structure for its lower part, a newly developed camshaft drive chain and gear system and a metal honeycomb catalyst with an air pump start-up system are also utilized.

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.