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This paper traces the more than 20-year history of fiberglass reinforced plastic (FRP) as the primary body material for the Chevrolet Corvette. Reasons for the original decision to use FRP are reviewed, followed by a discussion of the difficulties encountered in design, manufacturing techniques, and material compounding. These problems, and the solutions to them, include the progression from the original wet-mat material to low-profile systems. Sheet molded compounds (SMC) are discussed as non-low profile and low-profile applications. Unresolved production problems and outlined with a review of industry attention necessary to assure continued FRP application to Corvette body panels. This paper also discusses the design and application of flexible facias used on both front and rear-end bumper systems and the use of plastic as a bumper energy-managing system.

A few P/M fabricators currently are producing alloy parts which have high hardness in the as-sintered condition. These parts are intended for applications requiring high-wear resistance in service. The chemistries of the alloys used generally are proprietary. The objective of this paper is to describe for P/M fabricators and end users the metallurgical principles involved in designing the alloy chemistry to produce parts of this type; that is, the types and amounts of alloys are described which will suitably alter the phase transformation characteristics so that martensitic microstructures are produced during sintering. An understanding of these principles could lead to expanded usage of alloy wear-resistant P/M parts.

A comparison of standard methods of joining P/M structures, as well as new techniques. The porosity of a P/M part is no longer a problem when joining P/M to P/M or P/M to wrought. These joints will be as strong or stronger than the P/M material. The systems give the design engineer more flexibility.

The Ford Motor Company has developed a mathematical model utilizing electronic data processing techniques to calculate the potential savings to owners of automobiles equipped with energy absorbing bumpers. This model can be used to measure the economic effectiveness of alternative bumper performance requirements and/or system design proposals. Base data for the model has been obtained from surveys conducted by Ford of damage to pre-FMVSS 215 controlled vehicles. A description of the technique utilized to predict bumper system economic effectiveness and the results of Ford Motor Company's bumper cost-effectiveness studies are contained in this report.

The major factors influencing the cost-benefit relationship of improved bumper systems are discussed. Evidence is presented which demonstrates that energy-absorbing bumper designs have proved effective in reducing the frequency of crash damage, especially damage from low-speed crashes. Among the statistical sources utilized are State Farm's Current Model Year Study, Survey of Unrepaired Damage, Highway Loss Data Institute reports, and Insurance Institute for Highway Safety crash test results. Although the improved bumper systems are proving effective, the maximum potential cost savings are not yet being realized by consumers. This situation should change as standardization of bumper heights becomes more prevalent and as better data on the costs of improved bumper systems becomes available.

The sound pressure level (SPL) measured at a given point varies as a motor vehicle goes through a pass-by noise test such as SAE J986a. The tests described in this paper were intended to assess the magnitude and variability of different motor vehicle noise measurements. All factors which might cause variation in the received SPL were either controlled or monitored. This study was designed to quantify the effects on SPL from wind turbulence.

As the compliance with noise legislation became more difficult, Ford exhaust system development engineers increasingly encountered variances not only from vehicle-to-vehicle, but on the same vehicle tested in different locations. As a result, a series of tests were conducted to establish the correlation among various sites for vehicle exterior noise measurements. The purpose of this paper is to present the results and the method developed to achieve the correlation in terms of the following: 1. Ford and site equipment differences 2. Driver differences 3. Differences between site physical qualities Seven sites were evaluated in the program where seven vehicles were used with a good spread in exterior noise levels. A representative correlation plot is also presented which can be used to predict the expected noise level of any vehicle at any one of these test sites knowing the level obtained at the Ford site.

A series of road, engine, chassis dynamometer, and accessory power consumption tests was conducted in order to characterize the fuel economy of 1973 standard and intermediate size vehicles. Devices and systems which appeared to offer fuel economy benefits were evaluated by means of an analytical procedure. The study was limited to hardware which could be in production by the 1980 model year. The evaluation procedure was based on urban and steady speed operation, and the effects of compliance with future emission standards were included. Combinations of individual improvements were selected and applied to the same vehicle. The evaluation procedure was repeated, and fuel economy improvements of 30 to 70% were predicted by comparison with 1973 model year vehicles.

The fuel economy data obtained from the emission tests run by the U.S. Environmental Protection Agency (EPA) have been used to show passenger car fuel economy trends from model year 1957 to present. This paper adds the 1975 model year to the historical trend and concentrates on comparisons between the 1975 and 1974 models. Methodologies which allow different 1975 vs 1974 comparisons to be made have been developed. These calculation procedures allow the changes in fuel economy to be determined separately for emission control systems, new engine-vehicle combinations and model mix shifts. Comparisons have been calculated not only for the fleet as a whole but for each of the 13 manufacturers who were certified as of the time this paper was prepared. The net change in fuel economy for the fleet has been estimated at +13.8% comparing the 1975 models to the 1974 models assuming no model mix change occurs.

The European passenger car engine lubrication requirements are not the same as the American requirements. The differences are determined by the eingine design trends, the nature of fuels used and the type of service. The European engine and petroleum industries have undertaken the study of engine oil evaluation tests that meet European requirements. On the basis of the present standardized tests, engine manufacturers have recently proposed a specification for crankcase oils. This paper discusses particularly the European tests as to repeatability, reproducibility and correlation with service. Mention is also made of the recent European proposals for revision of the SAE Crankcase Oil Viscosity Classification.

A CEC Investigation Group has examined temperatures in European gasoline engines. A survey showed top quartile average temperatures of 275°C (top ring groove), 147°C (sump) and 163° (cam/follower oil gallery and main bearing exit), under high speed driving conditions. Forecasts indicated sump temperatures would increase by 10-15°C, partly related to emissions control systems. Consequent problems were predicted as wear, scuffing, oil oxidation, ring sticking, high oil consumption, and bearing/seal distress. Development targets for lubricant high temperature performance tests are discussed, and the severities of a number of possible ring stick tests are compared. A similar CEC Survey concerned high-speed diesel engines. This covered both small passenger car, light van diesels, and larger truck diesels. Increasing ring and oil sump temperatures were identified.

The viscosity change of multigrade motor oils in service has been evaluated in a fleet representative of the present European car population. The evaluation covered air- and water-cooled engines, with conventional and integral gearboxes, and displacements ranging from 500-1750 cc. The effect of car, service, average ambient temperature, and type of polymer on the viscosity change of a lubricant has been estimated. The multigrade test oils have also been run in injector and bench engine tests in order to compare field testing results with laboratory techniques being developed.

The exhaust emissions from a single-cylinder spark ignition engine were measured as a function of burning time. Flame propagation time was measured with an ionization probe, and the exhaust gas was sampled with a gas sampling valve. Electronic control logic determined the cycles to be sampled, based on the flame propagation time. Tests were carried out at full throttle, for lean, optimum, and rich A/F. The exhaust components measured were CO, HC, O2, H2, and N2 using a gas chromatograph. The emission most affected by CBCV is CO. Cycles that are either faster or slower than the mean cycle have increased CO, particularly at lean A/F where a five-fold difference in CO concentration was measured. HC emissions show a 150% change for the same conditions. For other than lean A/F operation, H2 was an exhaust product, up to 6% at rich A/F operation. It is well established that reductions in CBCV would improve efficiency and power output.

CEC investigation group IGL-8 has conducted a survey of European engine cold starting and oil viscosity requirements. The group's objectives were to determine if the 20W bracket was too wide for European use and what alternatives existed for improving the matching of oil quality to manufacturer needs. A study of engine cranking speeds showed that the span of the 20W range is twice that of the 10W range for European cars. Car Cold Startability, and weather data analysis, also showed that the span covered by the 20W range was double that for the 10W range, and that a critical winter temperature for many more temperate countries was - 10°C (14°F). For many cars, an oil in the 48-64 poise range at - 18°C (0°F) would provide 95-97% confidence of starting in the coldest month-January-and would best match their needs. Some diesel starting data, particularly on small, high-speed engines appeared to show the same trends.

The chemiluminescence determination of NO, and of NO2 after conversion to NO, is capable of yielding quantitative results for concentrations ranging from ppm to 1%. In using the chemiluminescence method for automobile exhaust, fast response and specificity are additional benefits. There are many possible sources of error in sampling, transporting, and analyzing auto exhaust samples, particularly when appreciable amounts of NO2 may be present. This paper discusses sources of error and how to detect and minimize or eliminate them.

Regarding the utilization of space and savings in vehicle weight and cost, greater demands are made upon compact cars than on larger automobiles. The development of compact cars, therefore, requires a higher degree of care and expense. The designer is forced to compromise more than he would in the case of larger vehicles. This paper examines some present day problems which are of particular interest with respect to driving safety when we regard the development of the chassis for compact automobles. These problems include suspension suitability for radial tires, axle kinematics, vibration characteristics, brake system design, handling, and legal requirements.

Wind tunnel tests were conducted on a series of 1/4-scale, 1/6-scale and 1/8-scale models of various automotive configurations utilizing a wind tunnel fitted with adjustable ceiling and sidewall inserts. Force, moment, and static pressure distribution data were acquired and used to develop corrections which appear to account for the constraints imposed on the flow field about these bodies by solid tunnel walls. In addition test section size limitations are defined for the acquisition of reliable data from automotive configurations.

A program was conducted to evaluate the performance characteristics and to determine cost effectiveness relationships associated with various prototype gasoline vapor control systems for service stations. Eight participating petroleum companies provided test facilities employing the direct displacement vapor control concept for evaluation during the summer, fall, and winter seasons. Test results indicated that the direct displacement systems had the potential for controlling approximately 95% of the vapors that normally are emitted when a tank truck delivers fuel to the underground tank and when tight connections at the vehicle fill neck are obtained. One petroleum company provided a refrigerated-condensation vapor control system for evaluation which exhibited the potential for virtually 100 percent vapor control, again when tight connections at the vehicle fill pipe could be achieved.

This paper outlines design considerations and criteria used to construct a prototype vapor balance gasoline nozzle. The nozzle incorporates a particular magnetic material on the face of the vapor recovery boot with a synthetic polymeric material on the sealing surface. A specific vapor recovery boot design is revealed which assists mating to the surface of the fill pipe. This nozzle was evaluated on 47 in-service vehicles at a specially equipped, commercial station in Chino, California. The prototype nozzle was solely supported by the automobile fill tube. Fill pipe-nozzle interface losses, car vent losses and station vent losses are all counted in the overall performance of the system. Percent vapor control was 88.9%. The investigators suggest that a fill pipe designed for vapor recovery would routinely yield results in the high 90s.

Several sets of repetitive test data using the 1975 Federal Test Procedure ('75 FTP) have been analyzed to establish the variability of each component measured during each phase of the test. The variability characteristics of four different emission control systems have been discussed and compared. The overall variabilities of the '75 FTP composite values have been assessed at ±6% for hydrocarbons and CO, ±3% for NOx, and ±1% for CO2. The extremely repeatable behavior of the CO2 emissions is utilized to calculate the fuel economy during the test. This calculation is discussed and some fuel economy results from repetitive tests are presented.