EcoBoost Stages 4-Cyl. Encore

Ford Motor Co. has plenty to crow about with the technologically advanced 3.5L EcoBoost V-6 that landed recently on the 2010 Ward's 10 Best Engines list in its first year of eligibility.

With 365 hp, 104 hp/L and 350 lb.-ft. (475 Nm) of torque in the Taurus SHO, the direct-injection twin-turbo V-6 stands as king of the 6-cyl. hill.

On paper, the EcoBoost V-6 even trounces a number of larger V-8s, including Ford's own 4.6L powerplant in the '10 Mustang GT, which soon will be replaced by a 412-hp 5.0L V-8 in the '11 model.

So where to now for the performance-enhancing powertrain configuration that will be available in more than 90% of Ford's vehicle lineup by 2013?

Befitting the stated mission for EcoBoost, the next application will support the trend toward downsized powertrains: The '11 Ford Edge cross/utility vehicle arrives this summer with the all-new 2.0L EcoBoost I-4 as the base engine.

Ford has not yet released output numbers for the 2.0L EcoBoost, but powertrain Vice President Barb Samardzich said last year the engine is expected to produce at least 230 hp and 240 lb.-ft. (325 Nm) of torque.

The new 4-cyl., assembled in Valencia, Spain, is a bid for optimal fuel efficiency in the growing midsize CUV segment. Ford promises the 2.0L single-turbo direct-injection gasoline engine will improve the Edge's mileage some 15% compared with the normally aspirated 3.5L V-6 that currently powers the vehicle.

That engine is rated at 18/25 mpg (13-9.4 L/100 km) in city/highway driving for the front-wheel-drive Edge and 17/23 mpg (13.8-10.2 L/100 km) with all-wheel drive.

A 15% gain for the front-drive model would put the I-4's fuel economy at about 21/29 mpg (11.1-8.1 L/100 km).

Is the 2.0L EcoBoost up to the challenge of motivating the all-new 5-passenger Edge?

As a front-drive model with the 3.5L V-6, the Edge weighs in at 4,082 lbs. (1,852 kg). That's slightly lighter than the 4,368-lb. (1,981-kg) AWD Taurus SHO, which hosts the 3.5L EcoBoost.

The Taurus SHO's porkiness prompted the only criticism from Ward's editors of the EcoBoost V-6 in the recent 10 Best Engines evaluations.

Although the V-6 is rated by the Environmental Protection Agency at 25 mpg on the highway, some editors reported the SHO's overall fuel economy in line with the city rating of 17 mpg.

For perspective, most models of the new Fiesta compact car, which goes on sale later this year with a slightly smaller 1.6L I-4, will tip the scales at less than 2,600 lbs. (1,179 kg).

Automatically expecting the 2.0L I-4 to feel underpowered in the new Edge is to ignore the inherent qualities and capabilities of EcoBoost.

It's possible some Ford customers like the current Edge but said the 3.5L V-6 gave them more horsepower (265) than they needed. Consumers clearly are factoring fuel-economy concerns into vehicle purchase decisions, so Ford is banking on the market supporting a 4-cyl. Edge.

Ford says I-4s make up about a third of its U.S. engine volume, and that percentage is bound to grow.

The EcoBoost 2.0L is about 55 lbs. (25 kg) lighter than the normally aspirated 3.5L V-6, and Ford considers the 2.0L to be the first truly global EcoBoost engine.

The engine will be available in the S-Max and Galaxy multipurpose vehicles in Europe beginning in April and also will join the powertrain lineup in the '11 Ford Falcon in Australia.

Additional U.S. applications for the 2.0L are due this year for Ford Explorer and likely the new '12 Focus next year. Ford expects I-4s will make up 66% of the EcoBoost lineup by 2013.

The 2.0L comes from a different architecture but shares many of its basic elements with the 3.5L EcoBoost, including all-aluminum construction, four valves per cylinder and a turbocharger that spools up quickly for maximum torque.

Although the V-6 reaches peak torque by 1,500 rpm, the I-4 takes a little longer (2,000 rpm) but holds steady until 5,500 rpm for what promises to be a delectable bit of mid-range punch.

And like the larger 3.5L, the 2.0L EcoBoost engine adds Twin Independent Variable Camshaft Timing (Ti-VCT), which enables precise variable timing control of both the intake and exhaust camshafts. Ford is incorporating the technology into several normally aspirated engine programs debuting this year in the Edge, Mustang and Lincoln MKX CUV.

Ford says the ability to vary the overlap between the intake and exhaust valves helps eliminate gas-exchange pumping work, boosting fuel efficiency about 4% compared with non-VCT engines.

And because the Ti-VCT strategy allows the intake valve to be advanced, Ford says instant power is delivered when the customer demands it at low speeds.

EcoBoost operates at fuel-injection pressures of up to 2,150 psi (148 bar) in the 3.5L V-6 and 2,200 psi (152 bar) in the upcoming 2.0L, which is common for most solenoid-based DI engines.

Piezo electronics enable higher injection pressures, but at a higher price. Ford engineers expect piezo pricing will come down and will become more palatable for DI gasoline engines.

Overall, DI engines are more expensive because they have more parts and are more sophisticated. Ford estimates DI technology is about four times more expensive than conventional port-fuel injection, and that in 10 years DI should be only twice as expensive.

Even as auto makers worldwide ramp up DI engine programs, the industry also will be able to sustain PFI technology for many years to come, says Dean Tomazic, vice president of Engine Performance and Emissions for FEV Inc., an engineering services company specializing in powertrain development.

In low-cost compact and midsize sedans, the PFI system delivers good performance and meets emissions and noise targets, Tomazic says.

But auto makers must step up to DI or turbocharged DI for the lowest possible fuel consumption, potentially paired with other technologies such as dual independent cam phasing and variable valve lift systems.

“Due to the more stringent CO2 targets in Europe and the U.S., the turbo DI configuration will continue to increase its market share in the U.S. and Europe,” Tomazic says. “Since the application of DI technologies is often dependent on fuel quality, its application may be limited in other markets around the world.”

But as long as fuel quality improves around the world — and a premium is placed on performance and fuel efficiency — he anticipates steady growth for DI technology.

Meanwhile, Ford considers the 3.5L EcoBoost V-6 to be an absolute homerun, selling well in the Taurus SHO, Flex CUV and Lincoln MKS fullsize sedan and MKT CUV. The take-rate for EcoBoost in the MKT is a healthy 48%.

ENGINE SPECS

FORD MOTOR CO.

3.5L twin-turbocharged DOHC V-6

Displacement (cc): 3,496

Block/head material: aluminum/aluminum

Bore × stroke (mm): 92.5 × 86.7

Horsepower (SAE certified): 365 @ 5,500 rpm

Torque: 350 lb.-ft. (474 Nm) @ 1,500-5,250 rpm

Specific output: 104 hp/L

Compression ratio: 10.0:1

Assembly site: Cleveland, OH, No.1

Application tested: '10 Taurus SHO

EPA city/highway (mpg): 17/25