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The breakthrough in low cost electronic switching devices has brought about the design of solid state, breakerless, capacitor discharge ignition systems. Through the use of a magnetic pickup, permanent magnets, and these new solid state devices, a maintenance-free ignition system can be designed. Through the use of these components, an ignition system can be designed to meet the particular needs of the 4-cycle engine.

High reliability and simple repair and maintenance make this breakerless capacitor discharge ignition system not only competitive but also vastly superior to those systems operating with breaker points and batteries. The new system is the result of developments in solid state switches and alternators using permanent magnets. This paper details the design, describes the operation, and outlines tests that substantiate its desirable capabilities.

The major deterrent to long term, service free life, of the conventional induction magneto used on small engines is the breaker point system. A multiple spark cycle, capacitor discharge magneto system, controlled by solid state switching, provides extreme long life operation without system deterioration. A simple electronic spark advance system can be included where necessary Modular construction affords ease of fabrication and provides design flexibility Consistent engine spark timing is assured throughout the life of engine and ignition system.

An operating system of automatic data acquisition and on-line computation as used in general engine testing is discussed. The considerations for its configuration are developed and operating history is reported. Included in the discussion are the parameters guiding the design of the system, method of operation, data format, and operating costs. An engine performance computer program is also outlined.

To implement a gas turbine development program, an engineering laboratory was expanded to provide five test cells and a process air station capable of delivering 30 lb/sec of air at 50 psig. An on-line computer controlled data system was included to speed data collection, reduce test reruns, and above all provide engineers with calculated results within minutes of the completion of a run. The paper gives a brief description of the facility and its data system, and shows how such a facility can contribute to a gas turbine program.

The philosophy, tools and techniques of value engineering are presented in this paper to offer to both those who are familiar and those who are unfamiliar with value engineering a new look at its use beyond cost control. The relationship of value engineering in employee motivation is discussed in this paper. The thesis that value engineering can be an effective program for managing progress and growth of a total company is presented.

The design and development of a unique three-ratio, hydraulic-shift auxiliary transmission utilizing a planetary and countershaft gear system is presented. Uninterrupted power transfer providing more efficient use of engine horsepower is prime objective.

Many of the modern, heavy-duty farm, construction, and industrial machines are being outfitted with some type of wet clutch. Either mechanically or hydraulically actuated, these oil-cooled multidisc clutches have much to offer when installed in the new higher horsepower equipment. The operation of wet clutches is outlined, and conditions of practical application are detailed.

Two balancer developments are followed through the conception and development stages into production. One design utilizes gear driven auxiliary flyweights, and the other, an oscillating counterbalance driven by crankshaft eccentrics. Vibration reductions up to 85% have been realized.

Application of the hydrostatic transmission to a farm and light industrial tractor involved many special design and manufacturing considerations. A brief description of the transmission is given, and some of the special considerations along with their solutions are discussed. Emphasis is placed on the importance of having the proper control system to provide desirable performance and endurance characteristic for the tractor. Because the controls of a hydrostatic by necessity are quite different than for a conventional tractor, particular emphasis is placed on the control portion of the overall development program.

After a short discussion of methods for measuring friction losses in diesel engines and the conclusion that it is not yet possible to determine accurately the true friction under firing conditions, motoring loss measurements for a number of automotive diesel engines of all sizes are presented. A simple formula that correlates this information is proposed. The breakdown of the observed friction into its components is examined in detail, permitting better understanding of the makeup of the total friction and of design changes necessary to reduce losses. A simple piston friction rig used to examine design parameters is described.

A review of benefits to be gained by automatically controlling the slip properties of truck tires indicates that up to 40% shorter stops and complete jackknife control when braking is possible. A simple all-mechanical device is described for use with air brakes which, from the data, shows 7-30% shorter stops, no tire degradation, and full steering control. Data is presented from full sized semi-trailer truck skid tests.

This paper attempts to illustrate some of the reflection characteristics of exhaust systems, suitable for piston ported, crankcase compression, naturally aspirated two-cycle engines. In particular, the application is even narrower, being concerned principally with those engines of the spark ignition, gasoline burning type where a high bmep is desirable. The two principal exhaust systems considered are the diffuser and the expansion chamber. Both are analyzed experimentally and theoretically and presented as measured and digitally computed pressure-time diagrams in simulated and actual engine exhaust systems. These are compared and discussed.

An emergency brake system for combination vehicles is described. It provides the driver with control similar to service brake control of all of the emergency brakes on combination vehicles, whether it is panic or controlled application. Operation of the modulated emergency valve is explained, as are valve characteristics, system timing, and installation.

Preventive maintenance is just as important in 1-cyl air cooled engines used in golf carts as it is in an automobile. The paper describes the characteristics of 2- and 4-stroke engines and then outlines the features of a maintenance program for them. Included are care of air and carburetor cleaner, use at proper speeds, use of fresh gasoline, spark plug and carburetor problems, and overall general care.

It is one thing for an engineer to design the safest vehicle and equip it with the most effective restraint system. It is quite another to have the user of this fine equipment use it to lengthen his own life. This paper explains the process one segment of a large government agency has successfully used to get approximately 88% use of the restraint system on the job and a slightly lower percentage of use by employee's families in the family car. Program emphasis has been on the 3-point lap/shoulder belt for maximum head protection.

The VTA-1710 series engine described represents Cummins' entry in the 800 hp class engine. This paper presents a general description of all design modifications that were made to achieve a 15% increase in power in the same package size with a conservatively loaded basic structure. Design changes to the engine are carried throughout the engine horsepower range of existing rating of 500, 635, and 700 hp to achieve a standardized family concept with a high degree of interchangeability.

This report is oriented to: 1. Research and development in highway transportation under sponsorship of the Bureau of Public Roads. 2. Traffic operations and control aspects of highway transportation. 3. Importance of combining vehicle engineering and human engineering along with highway engineering in programs to improve the service, effectiveness, and safety of highway traffic operations. As these new traffic systems, or improvements in the performance of highway transportation emerge, they will require new and far reaching decisions not only for highway users and administrators but for industry as well. Along with decisions there must also be commitments and investments of a scope and magnitude not experienced before. This report describes how new traffic systems are developing, what they consist of, and how they will be of benefit. It treats major features of new traffic systems which very directly involve vehicle and human engineering.

This paper outlines the conception and development of rating brakes. It is related to the adoption of the snub method of rating brakes as described in SAE Recommended Practice J880 and proposes an alternate continuous drag test method utilizing a dynamometer adapted to a road vehicle.

Modern data acquisition methods combined with new testing and analysis techniques are revolutionizing product design and development. Detailed analysis of recorded vehicle drive-line data has given today's engineer new insights into drive-line dynamics. This paper discusses how vehicles can be analyzed as a series of torsional springs and inertia masses. A two axle, 300 hp, 15 cu yd earthmoving tractor scraper (model 621) is used to illustrate significant factors. Main emphasis is on drive-line resonant torsional vibrations and shock loading. Diesel engines as torsional vibration exciters and transmission clutches as the major shock load producers are covered in some detail. How analog computers can effectively be used to facilitate vehicle development is briefly discussed.