Drivers' dream: better gas mileage

The record price of gasoline in the US has prompted a flurry of ideas about how to make a tank of gas last longer.

With the price of gasoline hovering at record levels, ideas are proliferating about how to maximize miles per gallon.

The Internet is full of unproven ideas such as adding a few ounces of acetone – yes, nail polish remover – to the fuel tank. Depending on whom you believe, it will either make the family buggy more efficient or potentially do harm.

Almost every consumer-oriented energy organization is counseling drivers to do things such as slow down, organize trips to avoid unnecessary driving, and keep the car tuned up. Such tips are endorsed by the US government as ways to save money and energy.

As the nation gets ready for Memorial Day, the start to the summer driving season, the average price at the pump is $3.24 a gallon, according to GasPriceWatch.com. That's about 2 cents a gallon more than the inflation-adjusted record set in March 1981.

Probably because of the rising prices, a recent poll by CBS News/New York Times found that 92 percent of Americans are in favor of requiring auto companies to produce more fuel-efficient vehicles. Sales of hybrid vehicles that achieve better fuel economy have now reached an all-time high of 2 percent of the current model year in the United States. [Editor's note: The original version misstated the size of the US fleet of hybrid vehicles.]

"This is the most interest we've ever seen in fuel economy by far," says Kateri Callahan, president of the Alliance to Save Energy in Washington. In the past week alone, she has done five television appearances. "An obvious sign is the ads from the automakers: They are advertising their fuel economy instead of the number of cup holders or movie screens."

Mileage issues are becoming increasingly important to the average family's pocketbook. In an annual survey, the Travel Industry Association found that the longest trip in the family car this summer will be about 1,000 miles round trip. Increasing mileage from 20 miles per gallon to 30 miles per gallon would save a vacationer $50 on the trip.

Over a year, the savings from this mileage increase would amount to $1,000, based on $3-a-gallon gasoline, calculates Ms. Callahan's group, which promotes energy conservation.

Thursday in Washington, the Joint Economic Committee (JEC) released a report that found the average family, based on current prices, will spend $3,180 a year on gasoline. Congress has yet to pass legislation that would mandate higher fuel-mileage standards.

"Increased fuel economy standards for our cars and trucks will save American families thousands of dollars, bring down out of control gas prices, clean our air, and reduce our dependence on foreign oil," said Sen. Charles Schumer (D) of New York in a statement. Senator Schumer is chairman of the JEC.

Despite the polls showing Americans want better fuel mileage, experts don't expect improvement to show up right away. "It's a slow process. It takes about 10 years to turn over the vehicle fleet," says Geoff Sundstrom, a spokesman for AAA in Heathrow, Fla.

Even if the process is slow, many Americans are scouring the Internet and other venues for ways to increase their mileage.

According to Peter MacGillivray, vice president of marketing and communications at the Specialty Equipment Market Association (SEMA), there are a number of well-known products that consumers can add to vehicles to increase fuel efficiency. "The industry is well aware of them," he says.

For example, performance-minded auto aficionados have for years installed a device that routes cooler, denser air from outside the car to the engine. The air filter then uses this air instead of the warm air under the hood. The part costs about $100 to $150. "That will without a doubt increase the performance of your vehicle," says Mr. MacGillivray.

SEMA has also conducted its own research on improving the fuel efficiency of pickup trucks. It found that adding a tonneau cover for the bed of the truck ($350 to $600) results in measurable gas-mileage improvements.

However, plenty of other parts and additives are more questionable. After the run-up in gasoline prices last summer, the Federal Trade Commission issued an analysis of gas-saving products. It cautioned: "Even for the few gas-saving products that have been found to work, the savings have been small."

In addition, the Internet is full of discussion groups that debate the pros and cons of ways to increase gas mileage, including the acetone idea. Some claim a "huge" increase in fuel mileage; others call it nonsense.

Jack Nerad, executive market analyst at Kelley Blue Book, which evaluates car values, says that adding acetone could at best do nothing, but at worst harm the engine. "It could dissolve seals, leave deposits in fuel tanks, and reduce the lubricating qualities of the gasoline," he says.

And Charlie Drevna, executive vice president of the National Petrochemical & Refiners Association, says he's not sure what acetone would do inside an engine. "We can't stop people from putting things in their tanks, but I'm not sure what it would do to their warranties."

Manufacturers of some of the devices maintain they have done independent testing that finds significant improvements in gas mileage and horsepower. One of those is the producers of the Vortec Cyclone, a device that fits inside an engine's air hose and makes the airflow swirl.

The device improves mileage by one to two miles per gallon and adds five to 12 horsepower, says Dan Baxley, a founding partner of the parent company, Automotive Research Laboratory in Hamburg, N.J. Larger engines get better results, he says.

"The [GM] Vortec engine utilizes this technology," says Mr. Baxley, who adds that demand for the product is at the highest level ever. "We have a return rate lower than 5 percent, so our customers must feel they are getting some benefit."

Mr. Nerad of Kelley Blue Book says the use of swirl is not a new idea. "From everything we have seen, it has a very limited effect, if any," he says.