For 2012, Ford is putting its Ecoboost technology to work in its popular Explorer and Edge sport-utilities, in a quest for better gas mileage. Previously available only with V-6 engines (which continue), the Explorer and the Edge are both adding a turbocharged, direct-injected 2.0-liter four-cylinder. Ecoboost for (nearly) all. If you think you've heard a lot already about Ecoboost, Ford's very clever and much-hyped brand name for direct injection combined with turbocharging, well, you ain't heard nothin' yet. Ecoboost is already offered in V-6 form in the Lincoln MKS and MKT, the Ford Flex and Taurus SHO, and the Ford F-150. By 2013, there will be an Ecoboost engine available in 90 percent of Ford's U.S. models. So there's lots more Ecoboost to come. The 2.0-liter turbo four is making its U.S. debut in the Explorer and the Edge. (The engine will be coming to the Taurus early next year, and is also slated for the upcoming Focus ST.) In the Explorer, it makes 237 hp and 250 pound-feet of torque; and for the Edge the figures are 240 hp and 270 pound-feet. Those numbers compare favorably to VW's 2.0T (200 hp, 207 pound-feet); but the Ford figures are less impressive next to Kia's 2.0-liter turbo (260 hp, 269 lb-ft). Ford Ecoboost 2.0L I-4, 237 hp, 250 lb-ft (Explorer) Ford Ecoboost 2.0L I-4, 240 hp, 270 lb-ft (Edge) Kia turbo 2.0L I-4, 260 hp, 269 lb-ft (Sportage) VW turbo 2.0L I-4, 200 hp, 207 lb-ft (Tiguan) 2012 Explorer Ever since the current-generation Explorer was previewed in 2008 with the Explorer America concept, Ford has said it would put a turbo four in the vehicle. The engine was not ready at the launch of the new Explorer late last year, so 2011 models came only with a 3.5-liter V-6. For 2012, however, it's finally here. Interestingly, the V-6 remains standard equipment, and the turbo four will be an extra-cost option ($995). The V-6 bests the Ecoboost engine in horsepower, with 290 hp (versus 237 hp), and -- just barely -- in torque, with 255 pound-feet (versus 250 lb-ft). Both engines are paired with a 6-speed automatic, but whereas the V-6 is available with either front-wheel drive or 4-wheel drive, the four-cylinder is front-wheel-drive only. The V-6 also tows more: 5000 pounds, to the four-cylinder's 2000 pounds. So what do buyers get for nearly $1000? Better fuel economy. Comparing front-wheel-drive models, the Ecoboost engine gets an additional 3 mpg in the city and on the highway. The actual Ecoboost figures are 20mpg city, 28 mpg highway (compared to 17/25 mpg for the V-6). Those numbers are extremely good for such a large three-row SUV. Because the Explorer is a large SUV -- and heavy, at 4500 pounds -- there is a trade-off in performance. Ford's internal testing puts the turbo four 0.8 second behind the six-cylinder in the 0-to-60 sprint (9.0 seconds vs. 8.2). On the road, the Explorer Ecoboost is able to get off the line reasonably well, but passing and merging require a bit of patience. Climbing grades, the transmission doesn't hesitate to downshift, which is helpful. What's most impressive, though, is that Ford engineers have managed to tune the turbo four to almost perfectly mimic the character of a V-6. There is no turbo lag, throttle response is linear, and engine note (when you can hear it -- it's barely perceptible when you're cruising) is notable only for its utter conventionality. In sound and feel, the turbocharged, direct-injected four-cylinder is little different than any transverse V-6 laboring away under the hood of a modern crossover/SUV. And that is exactly the result they were looking for. 2012 Edge Compared to the Explorer, the smaller, lighter Edge makes a slightly better home for the 2.0-liter Ecoboost four. Not only is the Edge some 500 pounds lighter than the Explorer, but the turbo four actually makes more power and torque in this application. Its 240 hp is still less than the Edge V-6's 285 hp, but the torque figure of 270 pound-feet actually beats the V-6's 253 lb-ft. Even so, here as in the Explorer, the Ecoboost engine is only available with front-wheel drive. And here too, the V-6 will be the obvious choice for people who do substantial towing, as its 3500-pound maximum towing capacity far exceeds the four-cylinder's 1500 pounds. Once again, the 3.5-liter V-6 is standard, and the Ecoboost four is a $995 option. (There's also an Edge Sport with its own V-6, a 3.7-liter good for 305 hp.) The Ecoboost engine ups this crossover's EPA ratings from 19/27 mpg city/highway to 21 mpg city and 31 on the highway. That puts it just behind some of its most economical four-cylinder competitors, such as the Chevrolet Equinox and the Kia Sorento (both 22/32 mpg); but neither of those vehicle's normally aspirated four-cylinder engines comes close to the Edge turbo four's output. Again in the Edge, the turbo four can't match the quickness of the V-6. Where Ford measures the V-6's 0-60 time at sprightly 7.3 seconds, it clocks the turbo four at a more sedate 8.8 seconds. But the Edge Ecoboost does not feel sluggish, and the turbo four's throttle response and sound quality do an excellent job imitating the dynamic character of a V-6. In both of these SUVs, the arrival of the Ecoboost four-cylinder offers buyers the opportunity to up their mpg, at a relative modest sacrifice in performance. The inability to pair the engine with four-wheel drive will naturally limit its appeal. It will be interesting, with a substantial number of buyers -- even SUV buyers -- now ranking fuel economy as a primary purchase consideration, it may be an idea whose time has come.