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The paper gives a description of a simply programmable electronic ignition control system that can be applied to the study of engine behaviour. This apparatus permits an easy change of the advance or retard characteristics as a function of RPM or vacuum.

A real-time hybrid computer simulation which is interfaced with an air brake truck is described. The simulation interconnects with the wheel lock electronic controller-modulator hardware and air brake system of a multiple axle truck to provide a laboratory tool for simulating vehicle braking performance. This technique provides controllable vehicle and road characteristics for evaluating the actual wheel lock and vehicle pneumatic system hardware. A set of comparative data is given and the merits of the simulation technique are discussed.

P/M Forging, introduced with much fanfare in the early 1970's, has overcome its initial technical problems and is beginning to achieve its early promise of significant economic savings. This paper reviews the technology development and goes on to detail the many well-suited applications which have been developed for automotive parts, farm equipment, hydraulic pumps and motors, outboard motors, chain saws, and industrial hand tools.

The heat balanced or combined cycle engine with time dependent combustion sustained by two chamber geometry is demonstrated experimentally. Evidence of time dependent heat addition is given where combustion creates a field of pressure waves sustained by pressure exchange between two chambers. The basic cycle and operating characteristics are reviewed and experimental results with CFR and glass-walled engines demonstrate the engine characteristic as compared to OTTO engines. Improvements in thermal efficiency over the OTTO engine in excess of 45% are demonstrated in some operating regimes. Considerable reduction in peak pressure and exhaust emission are also demonstrated.

The problem of highly rated turbocharged diesel engines operating under transient load conditions is now well known, and is due to the inability of the turbocharger to supply sufficient air for good combustion. In Part 1, two methods are discussed for reducing turbocharger lag-air injection onto the compressor rotor and oil injection onto a small pelton wheel mounted on the turbocharger shaft. Results are given showing the benefit of fitting these devices to an engine on a test bed. Engine response is improved in all respects particularly smoke and overall response time. In Part 2, a simulation study of a turbocharged diesel engine installed in a 32 tonne truck is presented to investigate the engine performance during load and speed changes. It is shown that by injecting compressed air on to the turbocharger compressor rotor tip, smoke emissions from the engine during load changes are reduced.

A recently completed HSRI study, “Effects of Commercial Vehicle Systematic Preventive Maintenance on Specific Causes of Accidents”, concluded that an identifiable relationship exists between good commercial vehicle inspection and maintenance practices and a reduction in defect-related accidents. The better maintenance practices were usually associated with larger firms, and poorer maintenance practices more often were associated with smaller firms or individual owner operators. Also documented was the need for improved or modified inspection and maintenance requirements as stated in the Federal Motor Carrier Safety Regulations.

This paper provides final results of an accident investigation project conducted by the Indiana University Institute for Research in Public Safety (IRPS), for the National Highway Traffic Safety Administration, emphasizing particularly the role of vehicular factors in causing accidents. In addition, these results are put in context with other recent studies which have provided information on the same topic. Data collection for the Indiana University accident causation study was confined to Monroe County, Indiana, where between 1970 and 1975, 2,258 accidents were investigated by teams of technicians using a consistent set of procedures and terminology. Concurrently, 420 in-depth investigations were conducted by a multidisciplinary team. Vehicular degradations, malajustments, and failures were identified as definite causes in 4.5% of these accidents by the multidisciplinary team, and in 4.1% by the technicians.

A five-cylinder variable displacement research engine has been designed, built, and tested for over one year. Displacement is varied by changing the piston stroke using a four-bar linkage. By proper choice of the linkage dimensions, compression ratio can be held constant as the stroke changes, or it can be tailored to optimize economy and performance. Before the engine was built, its dynamics were thoroughly analyzed, and a five-cylinder configuration was selected to minimize vibration. Test data show that BSFC is, as expected, less dependent on load than in conventional engines, and averages less than 0.5 lb/bhp-hr over the load and speed range of ordinary automobile operation. Several methods for estimating urban fuel economy from dynamometer data predict a significant improvement compared with conventional engines. Emission controls have not yet been applied to this engine.

Data from in-depth investigations of 1,087 incidents caused by vehicle defects reported to an automobile insurer were examined, compiled into various categories and analyzed. Significant results were that 530 (49%) of the incidents involved vehicle fuel system failures which caused fires. Brake system failures accounted for 301 of the remaining 557 incidents. Conclusions and recommendations are made supportive of countermeasures such as recall campaigns, upgrading of vehicle service facilities and vehicle owner education. The cost effectiveness of mandatory periodic motor vehicle inspection systems is questioned, further research, generally on vehicle safety defects and specifically on the causes of vehicle engine fires, is recommended.

This is a status report from the development of a 150 kW (200 hp) Stirling prototype engine intended for medium duty automotive application. The basic concept and some of the components were developed on a small 40 kW (55 hp) experimental engine of V4 configuration. In the report emphasis is laid on the presentation of the development of specific Stirling engine components such as heat exchangers and control system. The present status of performance as well as the final objectives are given. The installation of the engine in a truck and projected truck performance in a typical driving cycle are presented and discussed.

System analysis studies have shown that Diesel engines can be an alternative to spark ignition engines even in subcompact cars. According to some optimistic estimates, the share of Diesel engines in the total market may reach 25%, so that Diesel engines might well supplement the existing range of spark ignition engines. During the period from 1970 to 1990, the significance of all individual objectives whose demands are not favorable to the Diesel will decrease, whereas the significance of objectives favoring the Diesel will increase. It was the objective of the VW Passenger Car Diesel Engine Project to alleviate considerably all the ill-famed Diesel disadvantages, such as noise, smell, smoke, and slow acceleration, the latter being due to the low horsepower-to-weight ratio. On the other hand, we intended to preserve for subcompact car use the classical Diesel advantages, such as excellent fuel economy, long service life, low incidence of malfunctions, and favorable emissions.

The external heating system of the Stirling engine enables it to be coupled to a variety of energy sources. In the field of unconventional heating systems a high temperature thermal energy storage unit has been built in which, for the heat transport, use is made of the heat pipe principle. Based on experience with this, design considerations are given regarding the performance of an automobile propulsion unit, for which a new concept of a Stirling engine with a variable swash-plate drive and heating by a rechargeable thermal energy storage unit are used.

The Stirling engine holds out prospects of achieving a low pollution, quiet automotive power plant with excellent fuel economy and multi-fuel capability. N.V. Philips, of Holland, has been working with Ford Motor Company since 1972 on a joint program to build, test, and develop a conceptual version of the engine to determine its real potential. This paper describes the approach taken in the design of a four-cylinder double-acting 170-hp Stirling engine with a swash-plate drive, suitable for passenger car installation. Performance and steady-state fuel economy measured on a dynamometer are also presented.

The concentration of metals in crankcase oils has been used for many years as an indication of the wear of various engine components. The technique has also been used to study the influence of other contaminants as well. In these respects this technique has been useful in avoiding expensive maintenance or in spotting unusual operating conditions. Industry guidelines have been developed which are considered to be indicative of dangerous concentration levels. These guidelines have in general neglected to consider the influence of oil consumption and oil additions on wear metals concentration. This paper treats these questions and shows that they can be quite significant in some circumstances. The paper also shows that wear metals concentrations can be used to establish wear rates.

A simple valve is used in a Diesel fuel injection pump to allow each plunger to distribute fuel to two cylinders. The APS pump, based on this design, is both smaller and less expensive than an equivalent conventional pump because there are half as many pumping elements as engine cylinders. The APS pump has also shown significant performance advantages due to the action of the shuttle valves. A hydraulic governor has been designed and has been incorporated into the APS pump. This paper discusses the design and performance features of the APS pump.

This Diesel fuel injection system provides the capability of universal application to a wide range of existing engines. It also provides the injection quantities, characteristics, and timing variations which may be needed by the new high performance Diesel engines with emphasis on gaseous emissions and noise. This is an electro-hydraulic system using unit injectors which are electronically controlled and operate on the common rail principle. It features positive displacement fuel metering, hydraulic pressure amplification and nozzle valve control. The system is highly flexible and can achieve injection characteristics beyond the capability of conventional systems.

A study has been made of piston ring wear and total engine wear using literature data and new experimental results. The main purpose of the study was to establish the effects of oil and coolant temperatures on engine wear. Wear trends that were found in the early 1960's may not be valid any longer because of the development of higher BMEP turbocharged diesel engines, better metallurgical wear surfaces and improved lube oil properties. New data are presented for the purpose of describing present wear trends. A direct-injection, 4-cycle, turbocharged diesel engine was used for the wear tests. The radioactive tracer technique was used to measure the top piston ring chrome face wear. Atomic emission spectroscopy was employed to determine the concentration of wear metals in the oil to determine total engine wear based on iron and lead. The data were analyzed and compared to the results found in the literature from previous investigators.

The recent increase in excessive camshaft and lifter wear after extended service has shown that some SE-quality engine oils do not provide adequate protection. To determine the effects of oil additives on wear, controlled tests were run using 1972-1974 model cars, unleaded gasoline, and either SE commercial products or experimental formulations. Field experience with 1970-1975 model trucks, leaded gasoline, and SE/CC or SE/CD oils was also investigated. With some commercial oils, in both controlled tests and field experience, excessive wear sometimes occurred after extended service, even with recommended oil-change intervals. Generally, protection from excessive wear was best provided by those oils containing pre-dominantly alkyl ZDP (zinc dithiophosphate) antiwear additive instead of aryl ZDP. These results show that a laboratory engine test is needed to evaluate the long-term wear protection of engine oils.

The injuries of pedestrians involved in collisions with motor vehicles are analyzed in order to detect relationships between injury severity and documented observations. Data on pedestrian injury and involvement were obtained from three sources: Data on 265 involvements collected by Cornell Aeronautical Laboratories in Toronto, Canada during 1969-70; data on 175 involvements collected by the University of Houston, Houston, Texas, during 1971-73; and 47 cases investigated by NHTSA-sponsored multidisciplinary teams scattered throughout the United States. The data have been reviewed in order to correlate injuries with pedestrian age, area of body contacted, vehicle or environment contact surface, and impact speeds. The objective was to obtain knowledge to evaluate vehicle design and configurations as a possible means of reducing the severity of injuries inflicted upon the pedestrian when contacted by a motor vehicle.

The use of anaerobic adhesives and sealants has become widespread in the automotive industry in recent years. A particular form of anaerobic adhesive, the retaining compound, can offer significant improvements over mechanical methods in the mating of cylindrical parts such as the mounting of bearings, gears, pulleys, fans, cams, collars and flywheels. Possible benefits include increased reliability through greater strength, relaxation of machining tolerances, increased production rates, and reduction in rework and warranty costs.