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In 1981, Ford Motor Company introduced a new family of fuel efficient four cylinder engines world wide. These engines, based on a compound valve arrangement in a hemispherical combustion chamber, were specifically designed for installation in light weight front-wheel-drive vehicles. Ford Research efforts were integrated with the resources of Ford U.S. and Ford of Europe to design and develop the engine in a compressed time frame. The technical and organizational efforts to accomplish this task, as well as, the design and development are discussed.

A test cell was developed for evaluating a 6-speed automatic transmission. The target vehicle had an internal combustion 5.4L gasoline V8 engine. An electric dynamometer was used to closely simulate the engine characteristics. This included generating mean torque from the ECU engine map, with a transient capability of 10,000 rpm/second. Engine inertia was simulated with a transient capability of 20,000 rpm/second, and torque pulsation was simulated individually for each piston, with a transient capability of 50,000 rpm/second. Quantitative results are presented for the correlation between the engine driven and the dynamometer driven transmission performance over more than 60 test cycles. Concerns about using the virtual engine in validation testing are discussed, and related to the high frequency transient performance required from the electric dynamometer. Qualitative differences between the fueled engine and electric driven testing are presented.

The 2013 Ford Fusion will be launched with an optional automatic engine start-stop feature. To realize engine start-stop on a vehicle equipped with a conventional powertrain, there are two major challenges in the vehicle system controls. First, the propulsive torque delivery from a stopped engine has to be fast. The vehicle launch delay has to be minimized such that the corporate vehicle attributes can be met. Second, the fuel economy improvement offered by this technology has to justify the cost associated with it. In pursuing fuel economy, the driver's comfort and convenience should be minimally impacted. To tackle these challenges, a vehicle system control strategy has been developed to accurately interpret the driver's intent, monitor the vehicle subsystem's power demands, schedule engine automatic stop and re-start, and coordinate the fast and smooth torque delivery to the wheels.

Throttle tip-in/tip-out maneuvers generate a driveline torque transient which may produce an objectionable disturbance to vehicle occupants. Recent developments in vehicle design have contributed to increased severity in this response, which is known as clunk and shuffle. This paper describes experimental procedures which have been developed to quantify response levels and diagnose cases of concern. These techniques are useful for developing engine control systems which require transient strategies that differ greatly from those required for steady state operation. In addition, specific design and calibration modifications, which control clunk and shuffle, are described.

This paper explores the extent to which standard dilution tunnel measurements of motor vehicle exhaust particulate matter modify particle number and size. Steady state size distributions made directly at the tailpipe, using an ejector pump, are compared to dilution tunnel measurements for three configurations of transfer hose used to transport exhaust from the vehicle tailpipe to the dilution tunnel. For gasoline vehicles run at a steady 50 - 70 mph, ejector pump and dilution tunnel measurements give consistent results of particle size and number when using an uninsulated stainless steel transfer hose. Both methods show particles in the 10 - 100 nm range at tailpipe concentrations of the order of 104 particles/cm3.

Intake and exhaust valve control has been combined with engine calibration control by an on-board computer to achieve a Variable Displacement Engine with improved BSFC during part throttle operation. The advent of the on-board computer, with its ability to provide integrated algorithms for the fast accurate flexible control of the entire powertrain, has allowed practical application of the valve disabler mechanism. The engine calibration basis and the displacement selection criteria are discussed, as are the fuel economy, emissions and behavior of a research vehicle on selected drive cycles ( Metro, Highway and Steady State ). Additionally, the impact upon vehicle driveability and other related subsystems ( e.g., transmission ) is addressed.

An experimental modal model of an early prototype car was constructed and validated against test results. The model was then used to suggest practical hardware modification alternatives which would: (1) shift the steering column resonant frequency away from the idle range, and (2) maintain a low steering column tip vibration within the 600-750 RPM idle range. This model was also used to evaluate the effectiveness of tuning radiator mounts to the overall vehicle idle quality. It was found that a pair of braces from either the steering column bracket to brake pedal bracket or to the cowl top area could improve idle shake of the test vehicle. The driver side brake pedal brace alone is not effective. However, the passenger side brake pedal brace alone is as effective as the two brake pedal braces together. It was found that the radiator mounts on the test vehicle are extremely non-linear. Therefore, tuning the mount to improve idle quality is impractical.

A series of tests were conducted to determine the potential for reducing vehicle underhood temperatures by either 1) diverting the radiator fan air flow from the engine compartment or 2) by forced air cooling of the exhaust manifold in conjunction with shielding it or 3) by a combination of the two methods. The test vehicle was a Ford F-250 Light Truck with a 7.5L V-8 engine. The vehicle was tested in a dynamometer cell equipped with cell blowers to simulate road speed conditions. It was found that diverting the outlet air from the radiator will reduce underhood component temperatures when the vehicle is in motion and also at normal idle. However, if the vehicle is to be used for power takeoff applications requiring a “kicked” idle, then forced cooling of the exhaust manifolds is also required to maintain reduced underhood temperatures. A combination of these two techniques maximized the reduction of underhood temperatures for all operating conditions tested.

Exhaust pressures (P3) are hard parameters to measure and can be readily estimated, the cost of the sensors and the temperature in the exhaust system makes the implementation of an exhaust pressure sensor in a vehicle control system a costly endeavor. The contention with measured P3 is the accuracy required for proper engine and vehicle control can sometimes exceed the accuracy specification of market available sensors and existing models. A turbine inlet exhaust pressure observer model based on isentropic expansion and heat transfer across a turbocharger turbine was developed and investigated in this paper. The model uses 4 main components; an open loop P3 orifice flow model, a model of isentropic expansion across the turbine, a turbine and pipe heat transfer models and an integrator with the deviation in the downstream turbine outlet parameter.

A new estimator for IC engine A/F ratio is described. A/F ratio is important for engine operation since it determines the quantities of engine emissions, such as HC, CO, NOx, the conversion efficiency of catalyst systems, and the engine combustion stability. The A/F ratio estimator described in this paper is based on a fundamental metric that relies on inducing and detecting crankshaft speed fluctuations caused by modulating the engine's fuel injection pulse widths. Fuel pulse width modulation varies the instantaneous combustion A/F ratio crankshaft velocity. Synchronous measurement of crankshaft velocity provides a metric that, when used with other engine state variables as inputs to a conventional neural network, can accurately estimate A/F ratio. The estimator provides A/F information when a physical sensor is not available.

An analytical model is developed to describe the longitudinal response of the timing chain and the associated torsional response of all the sprockets and tensioner. A closed form equilibrium analysis reveals that equilibrium tensions are functions of tensioner stiffness, chain preload, steady cam torques and engine speed. The equations of motion are linearized about the equilibrium position to determine natural frequencies, mode shapes of the torsional modes and the forced response due to cam torque harmonics. Experimental measurements of the system natural frequencies and the forced amplitudes are in good agreement with the theoretical predictions.

Predicting the service lifetime of elastomeric automotive components is key to improving customer satisfaction over a 10 year / 150,000 mile desired lifetime. Achieving a good correlation between artificially aged components and those which have seen real customer usage can be a daunting task, considering the possible variations in climate, exposure and driver aggressiveness. In natural rubber (NR) components, the quantity and structure of the network crosslinks as a function of time can be used to explore some of the most basic aging mechanisms seen in the real world, as well as to validate protocols developed within the laboratory environment to accelerate the simulation of real-world mechanisms. This paper explores the findings of such a study on an NR engine mount, and examines the information learned by comparison between actual used components and test specimens subjected to accelerated degradation.

The electrical principle of operation, the geometrical and electrical circuit constraints on the design of, and the electrical and in-engine performance of a multigap spark plug developed for automotive applications are described. The electrical principle of operation is based on successively breaking down an array of spark gaps through the use of a resistive ladder network. The measurements evaluating the electrical performance of various multigap designs indicate that these plugs can deliver up to twice the energy of a single gap plug to the arcs, using the same ignition system. The increased amount of energy is also delivered in a shorter time than for single gap plugs.

The current Brazilian tax legislation promotes vehicles, powered by engines with up to 1.0l displacement. In order to offer the customer an engine with the maximum tax advantage, a supercharged derivative of the Ford 1.0l Zetec RoCam engine was developed. The market specific boundary conditions in South America require powertrains with immediate response especially at low engine speeds. This can be achieved by a supercharged engine concept. The paper discusses the required engine modifications for the supercharger application. The combustion system was changed to benefit from the higher volumetric efficiency, including the optimisation of the intake, exhaust and bypass control system. Extensive modifications of the base engine were required to adapt the engine to the higher thermal load and the specific boundary condition of a supercharger application.

Speciation of sulfurous acid, sulfuric acid and ammonium sulfate collected from the aerosol phase on a Fluoropore filter has been readily accomplished using techniques of chemical ionization mass spectrometry combined with thermal separation. Thermal separation of ammonium hydrogen sulfate from ammonium sulfate was not possible. Spectral separation of these species by selective ionization is proposed. Analysis of sulfate aerosols collected from ambient air and catalyzed vehicle emissions is described. It was found that sulfuric acid aerosol was rapidly converted to ammonium sulfate or ammonium hydrogen sulfate in the presence of ambient concentrations of ammonia. Ambient samples collected in the Detroit metropolitan area have been found to contain only trace quantities of sulfuric aicd. Sulfate samples collected from a dilution tube into which catalyzed vehicle exhaust was injected were found to contain significant quantities of ammonium sulfate in addition to sulfuric acid.

The microcomputer based ignition timing, EGR and fuel injection control system for the IIEC-2 concept vehicle is described. The techniques used to compensate the fuel delivery for EGR, to minimize response time and to compensate for engine and injector non-uniformity are emphasized. These measures, in conjunction with limit cycle air/fuel ratio control utilizing feedback from an exhaust gas oxygen sensor, are examined with respect to the effect on three-way catalyst performance.

Gas carburized and quenched low alloy steels typically produce surface microstructures which contain martensite, retained austenite and often NMTP's (non-martensitic transformation products). The NMTP's are caused by a reduction of surface hardenability in the carburizing process from loss of alloying elements to oxidation. Gas carburized low alloy steels such as SAE 8620 with NMTP's on the surface have been shown to have inferior bending fatigue properties when compared to more highly alloyed steels which do not form NMTP's, such as SAE 4615M. One method of minimizing the formation of oxides and eliminating NMTP formation during carburizing and quenching is to use plasma carburizing instead of conventional gas carburizing. In this study the microstructures and bending fatigue performance of plasma carburized SAE 8620 and SAE 4615M is compared to the same alloys conventionally gas carburized and quenched.

This paper discusses a motor vehicle noise source identification technique designed for use during the SAE J986a or similar drive-by test procedure. It provides, by application of the Fourier Transform, the capability to obtain a narrowband (9.8 Hz) frequency resolution over an extended frequency range (0-10,000 Hz) at the peak vehicle noise level, a particular RPM, or a particular vehicle location in the test zone. Other features include corrections for the Doppler shift, averaging of noise tests, and subtraction of spectra of two separate noise tests from a component disconnect/reconnect procedure. The above analysis, in conjunction with the noise source isolation resulting directly from the disconnect procedure, identifies the major vehicle noise contributors in terms of their respective amplitudes and frequencies.

High mileage NVH performance is one of the major concerns in vehicle design for long term customer satisfaction. Elastomeric components such as suspension bushings, engine mounts and tires function as vibration isolators in a vehicle. High mileage tends to cause the degradation of these components which in turn affects vehicle overall NVH performance. The present paper discusses the characteristics of bushing degradation based on laboratory bushing test data. Vehicle subjective evaluation and CAE modeling methods are used to develop a fundamental understanding of the effects of bushing degradation on vehicle NVH performance. The concept and analysis methodology are demonstrated using the front and rear suspension strut mounts and tire inputs which simulate road excitations but they are valid for other elastomeric components such as engine mounts and excitations. The knowledge derived in the study can be used as a generic guideline in designing vehicles for high mileage NVH robustness.

Sound attenuation and flow loss reduction are often two competing demands in vehicle breathing systems. The present study considers a full vehicle exhaust system and investigates both the sound attenuation and the flow performance of production configurations including the catalyst, the resonator, and the muffler. Dynamometer experiments have been conducted with a firing Ford 3.0L, V-6 engine at wide-open throttle with speeds ranging from 1000 to 5000 rpm. Measurements including the flow rates, the temperatures and the absolute dynamic pressures of the hot exhaust gases at key locations (upstream and downstream of every component) with fast-response, water-cooled piezo-resistive pressure transducers facilitate the calculation of acoustic performance of each component, as well as the determination of flow losses caused by these elements and their influence on the engine performance.