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Brake for Progress

Not all of the advanced fuel-efficiency technologies are still in the emerging stage. Even without camless engines and sophisticated software, assorted technologies for achieving better fuel efficiency are available. The list includes the “continuously variable transmission.” Unlike today’s automatic transmissions, which generally have four fixed gear ratios that clunk into place once engine rotation speed increases to a certain level, a continuously variable transmission delivers any of an infinite range of gear ratios on the fly. A Dutch company patented the technology decades ago; now the patents are expiring, and the transmission is already being installed in some models in the United States. The payoff can be big: in the 2002 Saturn VUE, the continuously variable transmission boosts fuel economy 7 to 11 percent, according to General Motors.

Improvements in fuel injection are also on the shelf, thanks to a recent advance known as “gasoline direct injection.” By replacing the traditional indirect-injection engine with this technology, the 2002 Volkswagen Polo has improved fuel economy for city driving by 13 percent. The benefit comes from exploiting the dynamics of how fuel and air mix. In the traditional indirect injection setup, gas and air are mixed outside the cylinder and then injected. With direct injection, fuel and air begin mixing only when they are inside the cylinder, enabling the engine to use an ultralean fuel mixture during steady, low-power driving.

All in all, there is no shortage of technology available and almost ready for the auto industry to adopt. And yet, SUVs still get an average of only 21 mpg. Asked why, General Motors’ Indra cites familiar industry arguments: innovations are too expensive; new components add weight, negating benefits. He says also that weight reduction-which, according to the DiCicco study, accounts for nearly one-third of the formula for boosting mileage-cuts into safety. That’s the argument the industry used as part of its lobbying blitz to kill tougher fuel-efficiency legislation last March.

Roland Hwang, a vehicles expert at the National Resources Defense Council, an environmental group based in New York City, says that argument is “irresponsible.” He claims the auto makers are fueling consumers’ fears about safety only to persuade them to buy bigger vehicles, which, he says, yield the highest profits. He notes that federal and insurance industry tests show that the safety record of SUVs is about the same as that for other cars. Even Honda America’s manager of environmental and energy analyses, John German, agrees that “if all vehicles weighed 100 pounds less, there would be no impact on safety.”

The larger point is simply that with no mandate from Washington or the public, the auto industry has little motivation to change. Doug Patton, a senior vice president at Denso International America in Southfield, MI, puts the subject into perspective: “What is the customer demanding? What is the government requiring? That’s how we look at it.”

To researchers, this is discouraging talk. MIT’s Heywood says most of these technologies have been in development for years. If the automakers wanted to, he says, they could readily make them inexpensive and reliable. “The car companies don’t give their engineers enough credit for being able to solve practical problems,” Heywood says. “Until management says, Okay, let’s really go for it,’ the technology doesn’t get past an advanced development prototype.” Giving such orders, he adds, “won’t happen until management thinks it has evidence that the technology will make the product sell in the marketplace or will create a new marketplace.”

Even if tough new efficiency laws are passed, others note, recent history suggests the auto industry won’t accede without a fight. “Industry leaders fought catalytic converters. They fought seat belts. They said air bags would bankrupt the industry. But once the requirements are passed they find a way,” Hwang notes.

For now, the auto industry is still content to fill showrooms with perennial gas hogs. But more efficient technologies-and the software to control them-are waiting for that final push into mass production.

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