By LAWRENCE ULRICH
New York Times News Service
As automotive earth saviors go, electric cars and hybrids are widely presumed to be the chosen ones. But as carmakers and consumers seek real, affordable gains in miles per gallon, it will be the once-humble 4-cylinder combustion engine that takes them there — far more than electrics or hybrids, which are years away from selling in numbers that would rein in the nation’s greenhouse emissions and appetite for oil.The new allure of 4-cylinder engines certainly defies the odds. From the ‘70s through the ‘90s, as Japan rode small cars to world-changing success, Detroit’s compacts were poor ambassadors for the 4-cylinder. American economy cars like the Chevrolet Vega and Ford Escort limped along with base-level 4s that were often rackety, unreliable and weak-kneed. When trucks, particularly brutish SUVs, became King of the Hill in the new millennium, buyers reflexively chose a V-6 or a thirsty V-8.
Today, though, American buyers shifting to smaller cars and lighter crossovers are discovering downsized engines strong enough to meet their needs. So far this year, 47 percent of new vehicles have 4 cylinders under the hood, according to J.D. Power & Associates, a remarkable jump from 30 percent in 2005. Over that time, the market share of burly V-8s has fallen to 16 percent, from 26 percent.
As for family sedans, more consumers are skipping the optional 6-cylinders for fuel-efficient 4s. Through July, 93 percent of Nissan Altima buyers chose the 4-cylinder version, up from 85 percent in 2007, just before fuel prices soared and the car market tanked. The 4-cylinder Ford Fusion, which attracted 55 percent of buyers in 2007, now accounts for over 70 percent of sales.
Those buyers are finding engines much more refined than the 4s of their parents’ generation — still stingy on gas, but surprisingly smooth and powerful. So much so that the modern engines, girded with power-aiding technologies like turbochargers and direct injection, can beat many V-6s in both horsepower and fuel economy. And the likelihood that Formula One cars, the epitome of racing technology, will soon switch to 4-cylinder engines might convince even a jaded small-engine skeptic.
Civilizing the 4-cylinder engine, a popular power source for American vehicles dating to the Model T, once posed a huge challenge. While in-line 4s can be elegantly simple, the up-and-down motion of their pistons produces an annoying — and unavoidable — imbalance that grows with engine size.
Modern 4-cylinders provide relief from the buzzing by using technologies that can quell the inherent noise and harshness, including counterbalance shafts, sophisticated combustion controls and improved sound deadening and engine mounts.
An alternate plan, used by Subaru today (and Volkswagen in earlier times), is to design engines that don’t generate the jitters in the first place. Boxer engines, whose four cylinders are laid flat in 180-degree opposition, naturally cancel out most vibration, without a need for balance shafts.
But while boxer 4s (or even the V-4s in many motorcycles) offer advantages in smoothness, automakers say modern in-line 4s are smooth enough to satisfy even the fussiest customers.
Still, for consumers like Jennifer and Jarid Lukin of Ardsley, N.Y., saving fuel and money remains the biggest lure. The couple recently traded their 6-cylinder Acura TL for a new Honda Accord EX-L and its 190-horsepower 4. The Accord is rated at 25 mpg in combined city and highway driving, compared with 21 for the Acura. “With our lifestyle, we didn’t need a 6-cylinder,” Jennifer Lukin said. “The 4-cylinder isn’t a racecar, but I’m not racing to day care.”
Hybrids, Jennifer Lukin said, might post even better mileage, but also cost thousands of dollars extra up front. Those kind of consumer calculations spurred Hyundai to draw up what seemed a bold strategy only a year ago: to build its 2011 Sonata sedan with only 4-cylinder engines — and no optional V-6. Now that choice seems prescient.
The midsize Sonata is selling well with a 2.4-liter, direct-injection 4 that is the strongest and most frugal in its class: 200 horsepower with 35 highway mpg. Compare that with 1990, when the Sonata’s 4 produced a puny 116 horsepower and just 25 highway mpg.
“These are good times,” said John Krafcik, chief executive of Hyundai Motor America. “Americans aren’t counting cylinders any more.”
This fall, the Sonata will offer a turbocharged 4 that combines 274 horsepower with a highway rating of 34 mpg. A Sonata Hybrid will harness an electric motor, lithium-polymer batteries and, yes, a gas 4-cylinder, to return 38 mpg.
General Motors’ Buick division has matched Hyundai’s strategy with its 2011 Regal. A version of the stylish Opel Insignia sold in Europe — where even big autobahn cruisers rely on smaller gas or diesel engines — the midsize Regal offers a choice of a 182-horsepower 4-cylinder or a 220-horse turbo 4.
Smaller engines also trim vehicle weight and development costs, and not simply because they are lighter or have fewer parts. Engineers, Krafcik said, did not have to spend time designing a stronger chassis for the Sonata to support a V-6 variant.
“If you have a V-6 in the lineup, it makes the 4-cylinder version heavier than it needs to be,” Krafcik said.
Let’s not overlook the green elephant in the room; this trend is not driven entirely by consumer demand or environmental consciousness on the part of automakers. Around the world, downsized engines are the linchpin of strategies to meet stricter fuel-economy and pollution rules, including limits on carbon-dioxide emissions.
In the United States, the regulatory bar calls for new cars and trucks to average at least 34.1 mpg by 2016, a level that would result in emissions of 250 grams of carbon dioxide per mile driven. That carbon cutoff is itself momentous: Cars will need to improve mileage to about 37.8 mpg, up from the current 27.5 mpg, with trucks rising to 28.8 mpg from 23.5 today.
Even at companies like Ford, which has ambitious plans for electric vehicles, leaders say that downsizing engines in mainstream products will save vastly more fuel than will hybrids, diesels or electrics — and at much lower cost to consumers.
Ford has pledged to put 1.3 million of its EcoBoost engines on the road by 2013 — two-thirds of them 4-cylinder versions — and to offer them in 80 percent of its model lineup. Brett Hinds, Ford’s manager of advanced engine design, called EcoBoost “the cornerstone of our sustainability efforts.”
Of course, if gasoline stays relatively affordable, Americans may resist the small-engine gospel and backslide into big V-8s. But Mike Omotoso, power-train forecaster for J.D. Power, said more consumers were resigning themselves to a world of higher-price gas and choosing their cars accordingly.
Ford is placing a big bet with the redesigned Explorer. The 2011 model will offer an optional turbocharged 2-liter EcoBoost with four cylinders. Yet that pint-size engine produces a surprising 237 horsepower and 250 pound-feet of torque — just 5 pound-feet less than the 3.5-liter V-6 alternative, with the tradeoff that it makes 53 fewer horses. It’s also expected to deliver 19/27 mpg in city and highway driving, Ford says, a 30 percent gain from the previous Explorer’s V-8. Built on the architecture of the Taurus, the new Explorer — now a car-based crossover — shaves several hundred pounds from the old pickup-based version, making a small engine more suitable. That engine alone trims nearly 100 pound
