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The importance of minimizing fuel consumption has necessitated the study of knock which drastically limits the attainment of high combustion efficiency in current s.i. engines. In the present work, four aspects of this phenomenon have been examined: 1. Knock intensity levels encountered during actual service operation of European cars. 2. Knock intensity levels that do not cause engine damage in endurance tests. 3. Factors affecting the knocking behavior of a fuel. 4. The meaning of the knock rating characteristics of a gasoline using the research and motor methods. It was found that the most severe knocking conditions were those met with by small displacement engines at a sufficiently high constant speed (4000-5000 rpm) and wide-open throttle. In these conditions, high knock intensities, much greater than the trace level, are needed to cause engine damage.

The state of the art of producing ceramic monolithic substrates for automotive converters is reviewed. The requirements for the substrates, that is, thermal shock resistance, stability, strength, porosity, softening temperature, thermal expansion and size tolerances are discussed, as well as the capability of manufactures to meet the specifications. The substrates are being produced for 1975 model automobiles. The primary production problems center around edge and corner chips and web thickness variations which occur in production and processing.

This paper describes a new application of Karman vortex shedding frequency as a velocity sensor in a motored internal combustion engine cylinder. The probe design, experimental setup and data reduction procedures are described. The quality of data obtained depends strongly on the relative frequency distribution of the free-stream turbulence and of the vortex shedding induced by the vortex generator. The instrument was evaluated on a CFR engine equipped with a shrouded intake valve. The results are presented in terms of the airswirl ratio at several selected crank angle degrees versus engine speed. The limitations of the device were also demonstrated in L-head engine tests.

An emission testing program conducted at Ottawa, Canada, indicated that the start-up and operation of light-duty motors at an ambient temperature of 0°F produces approximately a 100% increase in hydrocarbon and carbon monoxide emissions when compared with those produced at an ambient temperature of 60°F. This increase appeared to occur mainly during the initial 5 min of engine operation.

Three production cars and seven cars with various experimental exhaust emission control systems were tested to determine the effect of winter weather ambient temperatures on exhaust emissions. All of the cars were tested at 70, 40, and 20°F, and one was tested at 0°F using the 1972 EPA test schedule. Modal and bag emission data as well as catalytic converter temperature data were obtained. The results of these tests are presented in this paper. There was an increase in HC and CO emissions as ambient temperature was reduced. Most of the increase came from the first cycle of the 18 cycle test and was the result of additional time required to reach operating temperatures. NOx emissions did not vary substantially with ambient temperature.

A test program was conducted to study the effect of ambient conditions on exhaust emissions from a wide variety of automobiles. Twenty-six cars ranging from pre-control production cars to catalyst-equipped prototypes, including rotary, Diesel, and stratified charge cars, were tested at 20°, 50°, 75°, and 110° F. Ambient temperatures above and below 75° F were found to have significant effects on exhaust emissions. The Diesel and stratified charge cars were affected less than production and catalyst-equipped cars by changes in ambient temperature. The use of air conditioners at the 110° F test temperature led to increased emissions and fuel consumption. Hydrocarbon reactivity and aldehyde emissions were not affected by temperature and were lower from the catalyst cars at all temperatures.

A system to measure loads that a timing chain is subjected to has been developed. The system consists of a special sprocket transducer and associated telemetry equipment. The conventional camshaft sprocket is replaced by the special sprocket transducer which senses the torque and transmits it by means of telemetry to recording equipment. The system made possible the investigation of parameters that affect timing chain life and resulted in an improved timing chain design.

An accessory drive system, using a single belt, has been developed for engines with a full or partial array of accessories. The system can be applied to overhead cam engines with the use of a synchronous driving surface on one side of the belt. The drive system offers space savings and reduced assembly costs due to fewer and simplified components. Benefits to the consumer include lower maintenance costs and easy belt replacement.

The development of vehicular gas turbine engines to operate at temperatures up to 2500°F has been in progress for some time. The purpose of this paper is to review the rationale behind this engine, to highlight the major hot flowpath components being developed, and to provide information on the progress of this program.

The paper describes the factors which must be considered when assessing the suitability of a material for a rotary regenerator disc which runs at 1850°F. Mechanical and thermal stressing, thermal stability, and corrosion resistance are analyzed, using the properties of type CPD-5 material. This is a new lithium-alumino-silicate glass ceramic developed by Corning Glass Works. The environmental conditions assumed are those found in the 2500°F turbine inlet temperature engine which is being developed by the Ford Motor Company.

The 1974 Toyota Corona has been drastically changed to accomodate the required devices for emission control and to comply with safety standards. The handling and stability characteristics has been improved as well as vehicle performance. Steering effort and interior noise levels have been reduced. This paper presents the details of design concepts and the techniques that were employed to produce these improvements.

The recently introduced Volkswagen Golf, or Rabbit as it is known in North America represents the newest addition to the line of passenger cars manufactured Volkswagenwerk AG. The considerations applied in the establishment of design goals in the handling sector are discussed in the context of a description of the vehicle suspension system. The state of knowledge and administrative regulation of vehicle handling response characteristics are discussed in the context of design goals.

This paper presents a review of Curtiss-Wright's efforts to identify or develop successful apex seal/trochoid sealing systems for the rotary engine. Included are descriptions of the various wear test rigs utilized to evaluate apex seal/trochoid coating combinations. Laboratory seal-coating screening procedures are detailed along with engine test results. Seal-coating design considerations including factors affecting seal loading and wear are described. Data are presented on a newly developed plasma spray coating containing titanium carbide.

The radial lip shaft seal is a necessary, important component of modern machinery. A multitude of materials and designs exist for a variety of applications. The manufacturer must choose a seal type that will satisfy the conditions of the application with high reliability and long life. Confidence in the choice is gained through functional testing. Typical functional tests involve four to twelve seals. These tests are usually run under accelerated conditions. The seals must perform without leakage for a given period of time (typically 100-500 h). This technique (success testing) provides limited information with low confidence levels. Nothing is learned about the failure rate distribution of the general population of seals. A more meaningful statistical procedure, Weibull analysis, is discussed and applied to seal testing. Experimental data are supplied and analyzed.

The development of the Datsun pickup is traced from the post-World War II model with a wooden body, to the modified passenger car, to the current independent truck model. Some differences between the Datsun pickup and other Japanese-made trucks and American-made trucks are discussed. It is noted that the Japanese stress load efficiency: the Americans do not. Problems with size-dependent taxation rates; crowded roads; and scarce, expensive oil supplies have all led to a compact, economical design. Also discussed are the truck's adaptability to export destination requirements and its body construction.

A brief comparison of human performance in a man-machine system and in a Vehicular Transport System is carried out. Factors influencing the human performance are cited. Some of the problems connected with research work pertaining to VTS are summarized. Results of an experimental investigation, in which effects of road noise and vehicle speed on human performance were studied, are reported. The findings of the investigation indicate that noise is a significant variable as far as human performance in a VTS is concerned.

Inadequate training of the driver accounted for 70% of the 61 serious auto accidents investigated over a period of three summers by a team of field researchers. One conclusion reached following the study was that licensing officials must be granting licenses to drivers lacking sufficient preparation. Another aspect of the study dealt with the use of restraint systems. Figures show that, of the 138 persons injured in these accidents, only four were restrained at the time of impact.

This paper discusses the unique characteristics of the BMW 520. Beginning with overall specifications of the vehicle design, it proceeds to discuss in detail the front-wheel suspension and rear-axle systems. The adaptability of the suspension system to the requirements of diagonal ply conventional or radial tires is stressed, as is the simplified installation and maintenance of the front-wheel subassembly. The relatively friction-free steering system and the reduced steering effort achieved by the camber-offset axle are noted, along with the measures used to control steering vibration and wobble, as features incorporated in the BMW to achieve reliability, ease of maintenance, safety, and crashworthiness.

Reliability in a finished product can only be ensured when the designer has taken care to achieve the optimum solution to the sum of the needs of a particular set of circumstances. To follow this design philosophy, the designer must determine the function of the product, the length of time it will be required to operate correctly, and the amount of maintenance which is acceptable. When the necessary knowledge and information have been obtained from all available sources, then it is time to translate this concept into a product design. The engineering drawing is the message which communicates a reliable design to the production department so that it may be converted into a reliable product. The key to successful design is collaboration among as many designers as possible to maximize the amount of information and the number of ideas available, with one “manager of design” to coordinate their activities.

A recently completed research program has dealt with the problem of determining the influence of tire construction properties on vehicle braking and handling performance. Several tire properties that affect vehicle dynamic response have been identified and their effects quantitatively determined. Laboratory testing of a large sample of tires has shown that aspect ratio and basic construction type (that is, bias, bias-belted, radial) can significantly affect tire peak braking coefficient and cornering stiffness. The results of computer simulation studies and experimental tests with four automobiles have shown that the effect of changes in the peak braking force coefficient of tires on the average longitudinal deceleration of vehicles with fixed brake proportioning was small.