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September 30, 2011

News & Features

Automakers are making cars more aerodynamic and boosting mpgs

USA Today


Improved aerodynamics have boosted fuel efficiency in the Hyundai Accent (above), Honda Civic (below, left) and Chevrolet Malibu (below, right).

Other ways to save gas

You can boost your mileage with these tips:

  • Check your tires. Underinflated tires require more energy to roll, which eats up more fuel. Make sure your tires' air pressure is set to the automaker's recommended level.
  • Watch your speed. The harder an engine has to work to maintain a fast speed, the more fuel it needs. Each 5 mph you drive over 60 mph is like paying an extra 24 cents per gallon for gas, according to
  • Drive smoothly. Avoid hard acceleration and braking when possible. Use cruise control to maintain a constant speed.
  • Don't be a drag. Don't add to your car's aerodynamic drag by carrying things on top of the roof. For every 100 pounds of stuff you carry, you lose about a mile per gallon.
  • Practice maintenance. Using the proper oil will increase the efficiency of the engine, which will increase fuel efficiency. Don't ignore warning lights such as "check engine," even it the car seems to be running fine. A bad oxygen sensor could greatly affect fuel mileage.
  • Avoid excessive idling. "Idling gets 0 miles per gallon," points out.
  • Plan and combine trips. Several short trips taken from a cold start can use twice as much fuel as a longer multipurpose trip covering the same distance when the engine is warm.
  • -- The Associated Press, Consumer Reports

The government's tougher new fuel-economy standards are going to force automakers to go to new lengths to increase gas mileage, and many are already looking at fine details such as aerodynamics.

Coaxing buyers into smaller vehicles, slashing vehicle weight and cutting fuel use with turbochargers and hybrids will help automakers meet the 54.5 mpg national average required by 2025. But little steps will matter, too, such as how easily speeding cars slip through the air. "Every manufacturer will have to squeeze every tenth of a mile" per gallon, says Mark Perry, Nissan's director of Product Planning and Advanced Technology.

Here's how better aerodynamics are paying off.
Chevrolet Malibu: The 2013 model will see a significant improvement in aerodynamics with a shape approaching the wind drag of the Chevy Volt extended-range electric car, the best of all GM models. Some of the aerodynamic design seen on higher-end vehicles is finding its way to small cars, says John Bednarchik, an aerodynamic performance engineer at General Motors.

Hyundai Accent: The entry-level subcompact gets a 2.1 percent improvement in gas savings from reduced wind drag. Among other things, the car is fitted with an underbody panel to keep air from becoming trapped underneath, a feature previously found in more expensive cars.

Ford Focus: The new version, which went on sale this year, is 7 percent more slippery than the one it replaced. Among the changes were more aerodynamic side mirrors, wheel wind deflectors, a panel underneath the front end, shutters that close behind the grille at higher speeds and molding on the front roof pillars aimed at smoothing out air.

Nissan Versa: The subcompact is more than an inch lower than the one it replaces, to make it more aerodynamic.

Honda Civic: The new version has a rear spoiler and wheels that have a flatter surface to prevent trapped air. It gets a 3-mpg improvement. "It's the best fuel economy for a sedan with an automatic transmission in the industry," says Kurt Antonius, Assistant Vice President at Honda.

Designers and engineers have tried to perfect exteriors in wind tunnels since the gas shortages of the 1970s. They keep finding new tricks -- including the smallest ones. "Even the handles on the doors have an impact," says James Smith, past president of the Society of Automotive Engineers.


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