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A steady state vehicle model is developed that will predict engine and automatic transmission operating conditions based on various vehicle configurations and operating conditions. The model provides a better understanding of the effects, including direction and magnitude, of changes in vehicle configuration and/or operating conditions on powertrain requirements. The model results can then be used as input into powertrain matching decisions. In general, the model will begin by determining vehicle road load requirements (wheel speed and torque) as a function of vehicle speed based on ambient, road, and vehicle inputs. Such road load requirement will then be cascaded into input and output requirements of the rear axle, transmission gearing, torque converter (locked and unlocked), and finally the engine. Wide open throttle engine torque data will also be translated into tractive effort at the wheels and resulting acceleration capability versus the vehicle road load requirements.

The purpose of this paper is to present the design and assembly of a working prototype of an alternate fueled lawnmower. A variety of alternate fuels have been suggested to help reduce air quality problems. The conversion process from gasoline to Propane will be explained. To determine fuel consumption and developed horsepower, engine simulations were performed. Stoichiometric analysis was performed to determine and compare the products of combustion between Propane and gasoline. The prototype Propane fueled lawnmower is able to operate efficiently and with less emissions as compared with a comparable gasoline fueled lawnmower. Engine output has been reduced by 27%. By burning Propane, a relatively clean fuel, engine emissions have been reduced by 60% as compared to gasoline.

The 2000 Formula SAE Team at Lawrence Technological University (LTU) has designed a chain driven, three-piece aluminum differential unique from past years. This innovative design introduces an adjustable chain mount replacing conventional shackles. Made completely of aluminum, this device moves the entire rear drive train. The gear set remains to be limited slip with a student designed housing. The idea of an aluminum housing with manufactured gear set is a continued project at LTU. After cutting approximately 33% from the weight of the 1999 differential, the 2000 is geared toward a simpler, and smaller design, easier assembly and lighter weight. After reading this brief overview, the idea of this paper is to provide an understanding of the reasoning behind the choices made on the LTU driveline team. FIGURE 1

Two-stroke engine development has been occurring for many years. One of the main criteria affecting two-stoke piston-ported engine performance is scavenging,(4, 5, 10) which is the process of using the incoming fresh air charge to purge the cylinder of exhaust gasses. Among the simplest test procedures employed to model scavenging air flow is the “Jante” test, developed by Alfred Jante(1). This test was developed primarily to develop port designs for engines operating at peak power and so gives results having limited use for engines operating over a wide range. By altering the operating procedure as discussed in this paper, the Jante test can be used to provide useful information about the engine's scavenging characteristics over a wider range of engine operation. This offers a powerful tool for determining a porting design's effect on scavenging, and therefore engine performance.

Fouling spark plugs on an internal combustion engine is greatly influenced by cold temperatures, especially at older assembly plants where the vehicle is moved several times because of discontinuities in the assembly line. To transition the vehicle, the operator starts the vehicle, places it in drive and accelerates rapidly, then shuts the vehicle off. This process only lasts ten to fifteen seconds and does not allow the spark plug or engine to get to a high enough operating temperature to evaporate away the fuel, which fouls the spark plugs. A spark plug fouling test is devised and is used to investigate which properties of fuel play the most significant anti-fouling role. Some additives believed to have anti-fouling properties will also be investigated to determine their significance. The anti-fouling fuel will then be implemented at the assembly plants.

To obtain a maximum range for usable torque, Helmholtz theory is utilized to tune an Honda CBR 600 cc engine. The design objectives were to: 1) Increase performance by reducing pressure losses in the entire intake system; 2) Maximize the restrictor's design to increase airflow at lower pressure drops; 3) Improve throttle response through throttle body design and reduction of turbulence when full open; 4) Utilize runner design to improve tuning effects as predicted by Helmholtz resonance theory and; 5) Incorporate a plenum design with equal air distribution to all four cylinders.

One of the major components of the 2002 Formula SAE car is the base engine. Due to the restrictions put on the intake, the airflow into the cylinders is minimal. The air has to enter through a 20mm venturi, which drastically restricts the flow to the motor greatly reducing power. One of our main aspects will be focusing on improved airflow into the motor. Major improvements must also be made to the internal workings of the motor to regain this lost power. Through extensive cylinder head work and use of lightweight components, this can be achieved. Reworking the head for more efficient flow and raising the compression to approximately 13.1:1 will significantly improve power and torque.

A prototype engine intake design incorporating a required 20-millimeter restrictor is currently being evaluated for the 2001 Formula SAE competition. The engine is a 600 Honda CBR F4 four stroke. This carbureted stock engine was converted to fuel injection, requiring complete intake redesign. The primary difference from the stock intake design is the use of dual plenums, which prevents charging losses due to overlapping intake valve events. The throttle body and venturi design have also been improved. Preliminary test results are presented to validate design calculations and indicate potential for improvements.

A 1996 Kawasaki ZX-6R motorcycle has been converted from a four-carburetor intake and non-load sensitive ignition to a programmable electronic fuel injection system for performance enhancement. Throttle response and power delivery are greatly affected by proper fuel and spark management. Quick throttle response and smooth power delivery are particularly important in motorcycle road-racing applications. In order to achieve this a programmable engine management system is necessary. Due to turbulent air flow phenomena the fuel requirements of an engine can oscillate throughout the engine speed range. These airflow efficiencies are dependant upon many items including intake size and shape, camshaft design, exhaust design, surface roughness of the intake and exhaust ports, etc. In order to achieve proper air/fuel ratios, relative to rider demand, the current setup is not optimal.

Even with the rapidly evolving computational tools available today, suspension design remains very much a black art. This is especially true with respect to road cars because there are so many competing design objectives. In a racecar some of these objectives may be neglected. Even still, just concentrating on maximizing road-holding capability remains a formidable task. This paper outlines a procedure for establishing suspension parameters, and includes a computational example that entails spring, damper, and anti-roll bar specification. The procedure is unique in that it not only covers the prerequisite vehicle dynamic equations, but also outlines the process that sequences the design evolution. The racecar design covered in the example is typical of a growing number of small open wheel formula racecars, built specifically for American autocrossing and British hillclimbs.