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A review of passenger car performance trends over the past 18 years as observed from new car performance testing of a test car fleet (totaling 200 cars) is presented. The relation of the make-up of the test car fleet to the national average is shown. Trends in operating variables such as horsepower, thermal and volumetric efficiencies, fuel and air consumption, crankcase ventilation and blowby, octane requirement, vapor locking tendencies, and various temperatures are presented. Possible changes in these trends due to the incorporation of exhaust emission control devices on the vehicles of the 1966 through 1968 model years are considered.

Although the zinc-air battery system has been known for many years for its excellent energy storage characteristics (50–60 Whr/lb), the system has been limited in its applications by the low power output capability (< 1.0 W/lb). More recently, efforts have been made to increase the power output and maintain the good energy storage characteristics of this system. A mechanically rechargeable, 1-kW zinc-air battery has been designed, built, and tested which achieved a power density of 14–26 W/lb and an energy storage capacity of 30 Whr/lb. The battery weighed 72 lb and was used to replace 260 lb of lead-acid batteries as the power source in a 1-hp two seater Cushman electric cart.

The integration of a molten carbonate fuel cell with a molten electrolyte battery both electrically and thermally produces a highly efficient power source with a fast transient response. Since most practical high pulse applications utilize electronic chopping circuits, microsecond and millisecond response characteristics of a power source are of importance. Ceramic monoblock construction of a hybrid package can be designed with optimum response characteristics as well as the ability to accept high reverse power flow.

A sealed, secondary fused salt battery has been developed which has promise as a battery for electric automobiles. The battery uses active carbon plate cathodes, solid aluminum-lithium alloy anodes, and a fused lithium chloride-potassium chloride electrolyte. Cathode capacity is enhanced by the chemisorption of electrochemically active additives onto the carbon surface. The battery operates between 662 and 932 F. The best energy density achieved to date on a cell is 37.6 w-hr/lb. An improved carbon cathode being developed should enable an energy density of 70 w-hr/lb to be achieved. Insulation bus bars and internal heating coils are expected to add 15% to the weight of the battery. A five-cell battery of sub-optimum design has operated satisfactorily for short cycles. Parasitic leakage currents of less than 0.3% energy loss per hour have been demonstrated. Cycle life of over 1000 has been attained on electrodes.

This paper discusses the use of a time-sharing digital computer for computation of dynamic system responses. The program illustrated is a dynamic simulation of the linear vehicle directional control problem. State variable and matrix algebra techniques are used to calculate steady-state and transient responses of the linear directional control model for use in suspension analysis.

High energy density secondary battery systems are being considered for application in military electrical vehicular propulsion. Battery evaluation is carried out with a facility which controls tests by automatically maintaining electrical levels and changing modes of operation at preset limits. Lithium-chlorine cells tested and reported on demonstrate development improvement in energy output and efficiencies. Cell cycle life and rates are approaching goals for system applications. Responses of the system to milk truck and random military programs are analyzed.

This paper examines the many facets of vehicle handling and relates handling to real life conditions. Included in the paper is a description of driver-vehicle handling qualities in terms of safety and performance. The mechanics of accidents as well as the primary and secondary driving events influencing the accident situation are analyzed. The importance of the unexpected event is brought into focus and discussed. Subjective evaluation, performance task testing and response measurement methods are reviewed and compared in terms of merit in developing desirable vehicle handling characteristics. New test methods for measuring effects of braking and acceleration in cornering are described and illustrated with experimental results. The results of preliminary studies attempting to find correlation between objective measurements and subjective evaluation are shown.

Much has been published concerning theory and practice in the compaction and sintering of powder metallurgy articles. Nevertheless a gap exists between knowledge of the controls necessary in manufacturing practice and the resulting properties of fabricated powder-metallurgy articles. This paper is offered as an attempt to narrow this gap.

All mechanical properties of powder metallurgy (P/M) materials, including sintered nickel steels, are direct functions of sintered density or its inverse, porosity. Mechanical properties, such as tensile strength, ductility, impact strength, and fatigue limit, are dependent on sintered density, alloy content, and heat treatment. Other properties, such as the modulus of elasticity and Poisson’s ratio, are solely functions of sintered density. Sintered nickel steel with less than 8% porosity can be case carburized. Case hardening improves the smooth and notched fatigue limit of high density sintered nickel steels.

This paper reviews a wide scope of unconventional thermal, mechanical, and nuclear systems and devices to determine which, if any, might be suitable within the next 10 years for application as low-pollution-potential power sources for urban vehicles. It also points out which of those found suitable are most promising for such application. It is concluded that of the many types of unconventional non-electrochemical power sources that are even conceptually possible as vehicle drives, only three appear to offer the near-future possibility of supplanting the I.C. engine in many urban automotive applications; Rankine-cycle engines (which includes steam), gas turbines, and Stirling-cycle engines. For general urban automotive application, the Rankine-cycle class, followed closely by the gas turbine, appears to be the most competitive.

Model tests of several 0.1 hp free piston Stirling cycle engines were made. They showed good piston displacer phasing and thermal efficiency in the 10% range. An instructive isothermal computer simulation was developed which compared reasonably well with model data and allowed investigation of parameter changes. Some possible configurations, power transfer, and control methods were considered.

Throughout the development of a small sized passenger car, a simulation method using digital computers has been proved to be useful in achieving the desired dynamics. Among the types of independent rear suspension systems available, the semitrailing type has been shown preferable because of its negligible effect on jack-up. Ride motion is discussed within the concept of “dynamical pitching centers.” In some cases, shock absorbers proved very effective in controlling the pitching mode. A system having four degrees of freedom was used for the analysis of steering response. A practical method for evaluating driver reaction is proposed.

Studies of the equilibrium relationships and kinetics of the reversible reaction of hydrogen with magnesium-nickel and magnesium-copper alloys indicate that such systems have properties that may form the basis of a convenient and inexpensive method of storing hydrogen. This unique hydrogen storage technique offers the possibility of utilizing this clean and potentially economical fuel for motor vehicle propulsion. A vehicle propelled by a hydrogen-fueled internal-combustion engine would produce an exhaust that is inherently free of the hydrocarbon, carbon monoxide, and carbon dioxide pollutants that are major contributors to the atmospheric pollution problem in urban areas. The characteristics of this vehicular propulsion concept have been estimated and indicate that the hydrogen engine is potentially superior in performance to other inherently hydrocarbon-free propulsion concepts such as battery and fuel cell powered electric drives.

Computers for data processing and process control are being used for foundry management. Data processing applications are listed with brief explanations. The process control application is melting control of a 108 in. water wall cupola being continuously tapped into a 100 ton electric induction holding furnace. The process control computer project objectives, computer system, and instrumentation are described.

Do the brake fluid suppliers really know what the brake engineer wants from brake fluid? Of course they realize that the safety conscious brake engineer wants improvements in boiling point. But do they realize that he is interested in other characteristics which in the long run will help improve the end product - the automobile? One brake engineer speaks out about the characteristics he would like in brake fluids.

Engine development entails about equal measures of performance testing and durability, or life testing. The differing requirements of these two types of testing have resulted in separate data acquisition systems. For performance work the system design reflects the needs for flexibility, accuracy, considerable calculation of data, and for the printing and plotting of results. For a durability facility, where the output is test hours instead of data, the data system design stresses test monitoring and control. This system has not yet gone on line, although a hand wired system has been in service for ten years.

A number of fluid level warning indicators are currently available for adaptation to master cylinder reservoirs of the brake system. Their purpose is to provide warning of possibility of failure of the system in the immediate future. The types of indicators, degree of sophistication, advantages and disadvantages are discussed.

The precision of measuring the boiling point of high boiling brake fluids was determined by 18 laboratories on three brake fluid samples (374, 450, and 550 F). Tests were made using both a heating mantle and an electric heater. Reproducibility on the 374 and 450 F fluids. Two results (each the average of duplicates), obtained by analysts in different laboratories, should be considered suspect (95% confidence level) if they differ by more than 9 F. Reproducibility on the 550 fluid. Two results (each the average of duplicates), obtained by analysts in different laboratories, should be considered suspect (95% confidence level) if they differ by more than 19 F.

A major increase in damping capacity of pearlitic gray iron for brake discs has been obtained by modification of chemical composition. Car tests indicate that sufficient disc damping can be obtained to substantially reduce squeal tendency in disc brakes. The investigations showed that the frequency dependent damping is due to magnetoelastic and elastoplastic mechanisms at low frequencies. Apparently, the contributions from both mechanisms are enhanced by an abundance of large graphite flakes and a coarse pearlitic matrix microstructure. High carbon and silicon concentrations with minimal pearlite stabilizers are required. High damping capacity brake discs exhibited good braking characteristics and appeared significantly more wear resistant than conventional brake iron discs.

The mechanism of spray formation at high velocities is so complicated that it cannot be subjected to a complete mathematical treatment. Despite numerous studies made since Plateau, no reliable formula known can calculate directly and accurately the spray characteristics such as cone angle, spray velocity, droplet size, and droplet distribution indiesel engines. Here, an attempt is made to eliminate the complex, laborious, high pressure part of spray measurement and to calculate spray penetration by carrying out spray measurements in the atmospheric air alone.