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Making the Average Car in America Get 42 MPG
Making the average car in America get 42 miles per gallon is the biggest single step we can take to save oil and curb global warming. The key to getting there is technology: improved engines and transmissions; new lightweight, high-strength materials; and sleeker aerodynamic designs. To illustrate the potential new technology affords us, we've demonstrated how a popular car that meets the current Corporate Average Fuel Economy (CAFE) standards of 27.5 MPG could get 42.3 MPG. The technologies indicated by the arrows above are available to manufacturers, and most are already in production cars. The performance, size and safety of the car would remain the same, and consumers would save more money at the gas pump than the changes would cost. But auto makers won't do it on their own -- there needs to be a law. Technology is Responsible for Past Fuel Economy Gains Despite Ford's prediction in 1975 that a 27.5 MPG CAFE standard would make all its cars "sub-subcompacts," the company today offers a line of vehicles ranging from the subcompact Festiva to the large Crown Victoria. Efficient packaging, better fuel injections and other technologies accounted for 86% of the 100% fuel economy improvement between 1974 and 1991, according to Department of Energy analysts. Less than 2% came from reducing the size of cars. Today, Even More Technology is Available The current Taurus is no technological dinosaur. Its 27.5 MPG CAFE rating is twice that of its 1975 midsize predecessor, the Ford Torino. Today's Taurus has good aerodynamic styling, a 3.0L V-6 engine that achieves relatively low friction levels and incorporates multipoint fuel injection, and an electronically-controlled four speed automatic transmission with lockup. Safety features of the Taurus include a standard driver side airbag, an optional passenger airbag, anti-lock brakes and a structure that meets the new side impact requirements. But we've found room for a 54% improvement in fuel economy. Improving the fuel economy of the Taurus and other cars will save oil, curb global warming, slash the trade deficit, and save consumers money at the pump. 42 MPG Taurus Technologies in Detail 1.8L Multivalve Engine - 13% Improvement
Variable Valve Timing - 6% Improvement By allowing intake valves to close early during low power demand, valve timing in the 42 MPG Taurus will prevent inefficient pumping losses that occur in the current Taurus engine. Lean Burn Engine Technology - 6% Improvement Lean burn technology lets the engine burn less fuel ("lean air/fuel mix") under low pressure demand, but increases intake to admit more fuel when needed, such as during acceleration. Thus it makes the 42 MPG Taurus more efficient without compromising performance. High Strength, Lightweight Materials - 13.2% Improvement The weight of the 42 MPG Taurus is reduced to 2505 lbs. from the current 3131 lbs. by making extensive use of high-strength, lightweight materials as a substitute for steel. Fenders, body panels and even the vehicle structure, can be made from composite plastics which reduce weight without sacrificing function or safety. Aluminum, which is half the mass of steel, can be used for the structure and/or the engine. Because aluminum is so light, aluminum parts can be made thicker, thereby improving crashworthiness and making the structure stiffer for better handling. 5-Speed Transmission with Optimized Gearing - 9.5% Improvement A fifth forward gear provides 2.5% of the gain, while optimized gearing provides the remaining 7.0%. The latter saves fuel by reducing engine speed at a given power level by lower gear ratios (shifting sooner than in current transmissions). Electronic transmission control in the current Taurus and the additional forward gear make optimized shifting work better. High gear ratios are used currently in some production manual transmissions. Better Aerodynamics - 2.3% Improvement Though Ford was an industry leader in cutting vehicle body wind resistance (lowering coefficient of drag or CD) when it introduced the Taurus in 1985, the current Taurus' CD value of 0.32 no longer leads the industry. The 42 MPG Taurus' CD of 0.29 is 10% lower, improving efficiency 2.3% and matching the current domestic leader, the Olds Cutlass. (The Lexus LS 40 achieves a CD of 0.28 and the GM Opel Calibra sold in Europe achieves 0.26). Low Rolling Resistance Tires, Low Friction Lubricants and Improved Accessories - 5% Improvement. Current tires like the Goodyear GFE offer significantly reduced rolling resistance, boosting efficiency 2.0%. Available motor oils like 5W-30 reduce engine friction and improve efficiency 0.5%. More efficient pumps, alternators, etc. make air conditioning, power steering and other accessories use less power and improve fuel efficiency 2.5%. For more information, contact: Daniel Becker Up to Top |
The 42 MPG Taurus' 1.8L engine will have more power per
unit engine size than the current Taurus 3.0L engine design. Adding
2 valves to each cylinder ("multivalve" design) improves air/fuel
delivery and exhaust discharge, cuts pumping losses and dramatically
boosts output. Multivalve accounts for 5% of the 42MPG Taurus
engine's 13% efficiency gain and dual overhead camshafts to
accommodate the extra valves will boost efficiency another 3%, The
smaller 1.8L engine has fewer cylinders (4 cylinders instead of 6)
than the current 3.0L design, yet the performance of the 42 MPG
Taurus is the same. The switch to 4 cylinders accounts for 3% of the
13% efficiency gain. Better design and manufacturing of pistons and
cylinder walls in the 42MPG Taurus engine will eliminate some
friction power loss that occurs in the current design and boost
efficiency 2%.