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As long as economic considerations keep electric transport vehicles in the limelight of interest, the arguments raised in favor of the electric vehicle in general will prove unconvincing. In the drive system the separately excited shunt-wound D.C. motor is becoming widely acknowledged as traction motor; current developments deal with the replacement of electric power control units by mechanical components. Hybrid drive units are mainly employed in buses; so far no uniform solution has evolved. List prices of electric transport vehicles reveal the financial burden caused by energy storage units and their maintenance.

The “Four-Octane-Number Method” is a practical determination of the knock-resistance of fuels based on the autoignition delay concept and obtained through simple processing of the standard “Research” and “Motor” indices combined with two other indices specially defined. The knocking behavior of any engine can be specified once by measuring its octane requirement with 2 fuels for which the four octane numbers are known. The behavior of any fuel can be predicted without experimenting on all the engines thus identified if its four octane numbers are known. Extensive controls of the method have been performed over about 1000 samples for which the road octane numbers were measured. The method's predictions are within an average accuracy of 0.5 octane point.

This paper presents a statistical analysis of emission test results from over 200 light duty production vehicles ('72 to '77 models) which were purchased, maintained (in a very good state of tune), driven (on Appendix “IV” routes), and tested by the Canadian government. The results are presented as fractions of the applicable emission standard by manufacturer and by model year. Some limited data on urban fuel economy is also presented. The results would be useful in analyzing engine design policy and to assist in policy making for emission control programs for in-use vehicles.

Five light-duty vehicles were used to investigate HC, CO, and NOx emissions and fuel economy sensitivity to changes in the length of soak period preceding the EPA Urban Dynamometer Driving Schedule (UDDS). Emission tests were conducted following soak periods 10 minutes to 36 hours in length. Each of the first 8 minutes of the driving cycle was studied separately to observe vehicle warm-up. Several engine and fuel system temperatures were monitored during soak and run periods and example trends are illustrated. The extent to which emission rates and fuel consumption are affected by soak period length is discussed.

Three problem-solving methods used by engineers (personal contacts, experimentation, and literature searching) are defined and evaluated. Literature searching techniques and library resources, including library staff aid, card catalog utilization, use of indexes and abstracts, online information retrieval, and alerting services, are discussed.

This paper describes the results of an automobile exhaust emission testing program conducted by the U.S. Environmental Protection Agency. A total of 381 vehicles were subjected to a series of tests before and after various stages of tune-up. The vehicles were low-mileage 1975, 1976, and 1977 models of the three major domestic manufacturers and were obtained from private owners. Significant findings include the confirmation of the poor emission performance of newer vehicles when compared to their standards, the wide extent of maladjustments and disablements and the large emission reductions possible upon correction of these problems.

Scientists, engineers, information specialists, and other professionals are using on-line retrieval systems to locate information rapidly and precisely in large data bases of literature citations and abstracts. Many data bases are available for such searching, including one covering SAE publications. On-line searches can be carried out in minutes, with greater precision and lower cost than manual searches of equivalent quality. Most on-line searching is done by librarians and technical information specialists, but many chemists, engineers, and other professionals do their own searching. For some data bases, including SAE, users can order copies of the original documents, directly from the terminal.

Various families of constant velocity joints have been developed and applied in mass production vehicles, to overcome limitations imposed by cardan joints in automotive drive line applications. The special requirements of front wheel, rear wheel and longitudinal drive lines, as well as the different construction principles are specified and analysed. Furthermore the individual characteristics and features of the main GKN fixed and plunging joints are described. Forecast vehicle design requirements are identified which led to the development of a new constant velocity joint family.

A new four-speed automatic transmission with overdrive has been developed and put into production for the purpose of the improvement of fuel economy and the reduction of engine noise. The transmission has the following characteristics: Gear train arrangement having overdrive unit between the torque converter and the three-speed auxiliary transmission High overdrive gear ratio Shift feel controls for clutch-to-clutch shifting Optimum shift points between third and overdrive gears on fuel economy, driveability and exhaust emissions Lockout system of overdrive gear This paper describes the design features and confirmation testings considered to assure the reliability and durability of the transmission. It also refers to effects on fuel economy and noise of the transmission in the vehicle.

The average fuel-economy standards enacted under the Energy Policy and Conservation Act have stimulated domestic manufacturers to downsize new passenger vehicles. The strategies employed by manufacturers to maintain their competitive positions and the corresponding consumer response to down-sized vehicles are resulting in visible shifts in the marketplace. The disappearance of traditional size-class distinctions are discussed in the framework of the theory of consumer behavior and corporate marketing strategy. Preliminary input to consumer acceptance of down-sized cars underlines the need for advances in engineering and design to maintain an effective range of choice for the consumer.

Modern technology has now provided the engineering profession with a fast and effective means of communicating engineering technology. Machine-readable versions of traditional and new printed information sources and powerful software packages now enable engineers and others to retrieve information quickly, effectively and with a minimum of effort. In addition, access to multiple interdisciplinary data bases within minutes can satisfy several aspects of an engineer's question with a relatively small investment of time and money. Information sources in the online interactive mode now include machine-readable numeric data bases or so-called electronic handbooks, where actual data can be found.

For over 70 years SAE has provided a continuous forum for engineers to present their theories and findings in the form of technical papers. These papers provide the basis for the largest single collection of literature on automotive technology in existence. The problems of utilizing this vast “storehouse” of information are discussed as well as methods for keeping up-to-date with the current information explosion.

The results of a three dimensional finite element analysis of the stresses near the notch of the SAE keyhole fatigue specimen are presented. They are compared to plane analyses of the same area and also to data obtained from a three dimensional photoelastic analysis. The state of stress in the keyhole specimen is neither plane stress nor plane strain. Conditons at the midplane of the notch root are more favorable for early crack initiation than either of the plane formulations.

The mechanics whereby fatigue-improvement fasteners give rise to increased joint fatigue resistance is examined using the results of both analytical and experimental studies. The inferences of a brief review of the mechanisms of fatigue damage are used to demonstrate how each of the interference fit, cold work, and coupled cold work-interference fit systems improve fatigue resistance. Experimentally developed fatigue data for standard joint test configurations are then analyzed using the so-called critical location approach to fatigue life analysis. The results of this study are interpreted in the context of joint designs used in the automobile industry.

Recent advances in metal fatigue analysis are examined with a view toward the need to devise specific procedures for acquiring and processing strain or load histories in order to evaluate structures for in-service fatigue life. Emphasis is on location of waveform reversal points, omission of insignificant ranges, and on cycle identification. A damage and life calculation method is selected and used as an example around which to construct a complete procedure for prediction of crack initiation life from strain histories; alternatives are considered. A method of estimating the cyclic stress-strain curve is proposed.

Discusses federal regulations of fuel economy as a restraint of vehicle performance. Develops a case for the need for greater selection of gear ratios over the range of intended vehicle use. Describes the musts and wants for vehicle design. Relates the musts and wants to two-speed axles as a solution. Describes a two-speed axle design.

The use of signature analysis to determine the acceptability of parts in a production line quality control situation is highly desirable. Specifically, the use of acoustic signature analysis is attractive due to the relaxed constraints in terms of fixturing the part in preparation for analysis. This study discusses techniques presently being investigated which rely on knowledge of the modal coefficients to direct the area of investigation.

A torque converter lock-up clutch was introduced by Chrysler Corporation in a majority of its passenger cars in the 1978 model year. The lock-up clutch improves fuel economy by eliminating torque converter slip in direct gear above a predetermined speed. The clutch and its controls were designed to fit within the confines of the existing transmission. The development of the clutch was primarily concerned with achieving adequate endurance life, good shift quality and isolation of torsional vibrations.

This paper presents the theory and hardware to simulate non-loglinear spectra (the typical field case), including a unique method of eliminating low amplitude reversals so that any service load history of high cycle fatigue can be simulated in a laboratory fatigue test. The feasibility of the proposed quasi-stationary random process to simulate the three standard SAE load histories on a statistical basis is demonstrated on both the theoretical and experimental basis.

The basis of block load fatigue testing is the cycle counting method used to produce the test programme. The poor correlation with random loading often found may be due to the traditional counting methods. The paper discusses the new and more physically realistic “rain flow” counting method and presents test results which show that it can be used to give a more accurate simulation of random load fatigue damage than three traditional counting methods. The techniques advocated are particularly applicable to industrial fatigue testing where simple digital computing facilities are available.