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Friday, September 5, 2008

The Engine We(Ford) have all been waiting for

words: Stu Fowle

Today I'm in a displacement lover's hell. The trip from Chicago to Dearborn was made in record time, but not because of some big, burly V-8. The twin-turbo six of Motive's long-term BMW 135i was responsible for pinballing me through the mouth-breathing, truck-driving hordes of rural Michiganders along I-94. And here at Ford's Beech Daly technical center, the buzz inside is all about the upcoming EcoBoost V-6, which Ford hopes will provide V-8 power with V-6 efficiency. Suddenly, the whining from purists two years ago when BMW announced its first turbocharged gas engine since the '70s doesn't seem like a big deal. This is Ford. Mustangs and F-150s. V-8s and Toby Keith. And now that's all fallen to turbochargers and economy? What's next, painting the blue oval green? To peek behind the curtain and see exactly what's going on, I've come here to get my hands dirty. I'm going to build one of the first EcoBoost engines.

Slapping two Honeywell turbos on the 3.5-liter Duratec and calling it the V-8 of our gas-deprived future wasn't the knee-jerk reaction to $4 fuel that it might seem, and it wasn't as easy as it might sound. Work on the EcoBoost started in 2002, long before the marketing department dreamed up that name. Over one million miles have been logged on dynamometers and public roads in the time since, and over 120 engines have been torn to bits and examined under microscopes. There have been 150,000-mile fatigue tests, 360-hour durability tests, and even one part of development that involved 1500 cycles of making the exhaust manifolds glow red with heat then cool again before making another run. While many parts of the EcoBoost's naturally aspirated counterpart didn't change significantly, almost everything was at least mildly tweaked.

Michael Shelby, Ford's EcoBoost V-6 Engine Development Leader, greets me at the door of the tech center with a pair of safety glasses and a smile, showing that he's prepared to laugh at some media-type trying to build his company's most advanced V-6 ever. We head behind closed doors — lots of them — and past a vast room ripe with the smell of old motor oil and full of long benches, each of them covered with prototype engines cut open like dissected frogs in a high school biology class. If I were a real Ford geek, I'd probably have some breaking engine news for you at this point. But I'm not, so I keep following Shelby and probably miss some quad-turbo Boss V-8 hiding in a corner.

In the next room, an EcoBoost is laid out at a horseshoe-shaped table with the deep-down bits at one end and the intake parts at the other. The engine block is first in line, and it's basically the same chunk of aluminum found under the hoods of Fusions, Tauruses, and most other V-6–powered Ford products. But then Shelby turns the block on its side and points out a few key changes — the outside of the cylinder walls have been strengthened to withstand extra pressure, and there's a bit of extra machining at the bottom of each cylinder to accommodate a squirter that blasts oil at the bottom of each piston to aid cooling. Additionally, the oil pump has been upgraded to flow four more cubic centimeters per revolution.


The only other changes made to the short block come when we get up to the pistons, which have already been set in place and connected to the crankshaft for me. (It's all right, I wouldn't have trusted me, either.) An advantage of direct injection is the ability to control the quick, precise blast of fuel. To capitalize on this, the EcoBoost gets piston heads with a bowl cut into them. It looks a bit like a backyard swimming pool with an oblong shape and a deep end at the middle. I run my finger along in the path gasoline will take, making a whooshing noise that silences the room with awkwardness. The fuel comes in from the side of the cylinder, sprays into this bowl, and is directed right up toward the spark plug for more complete ignition. This extra bit of engineering is advantageous when the engine's cold and operating less efficiently.

That brings us up to the cylinder heads; big, bulky hunks of aluminum that threaten to cut my hands in 50 different ways. Shelby spins one around in his hands, pointing out the obvious changes before passing it off to me. Beneath the surface, larger and deeper cooling jackets draw more heat from the fuel injectors. Additional cooling lines flow out of the block and through each turbocharger to cope with 1742-degree F exhaust temperatures. Shelby's engineering team spent extra time on these seemingly simple hoses to promote thermal siphoning within them. That's a process in which boiling water inside the turbos acts as a pump to draw cooler water in, which in turn prevents thermal soak. You don't honestly expect soccer moms in Flexes to sit in the garage for a few minutes so that the turbochargers can cool, do you? I pick up the entire assembly and hold it up to our unfinished engine. It fits snugly against the heads and wraps around from one turbo to the other. Shelby says how proud he is of the tight packaging that'll allow the engine to squeeze into so many of Ford's cars.


Back inside the heads, three of the engine's four camshafts are essentially the base 3.5-liter's with valve event durations slightly modified. They look like any other cams, with sets of two lobes sitting down over each piston. I set one in place after resisting the urge to wield the heavy metal bar like a nightstick. The fourth cam is affectionately referred to as the "shish kabob" because of its peculiar four-sided lobe halfway along its length. It drives the high-pressure fuel pump added to feed the direct-injection system and I don't notice it at first glance. Then I feel silly, like a child not knowing why the square toy doesn't fit in the round hole.

The pump sends fuel under pressures as low as 200 psi and as high as 2900 psi into the injectors, which spray fuel through six small holes directly into the cylinders. For as complicated and revolutionary as direct injection is made out to be, the injectors themselves look like three unassuming nozzles dripping off from one main rail. Looking at the fuel pump housing, though, you'd think it protected a ball of plutonium. There's a giant chunk of metal protruding from the cam cover to ensure the fuel pump isn't ruptured in a frontal collision, plus a thick cover over the pump to limit noise and vibration from its solenoid. Anyone who owns a direct-injection Volkswagen or the turbocharged versions of the Pontiac Solstice/Saturn Sky will understand why that cover's there. Ford doesn't want anyone asking EcoBoost drivers if their cars are diesel-powered.


While the fuel side of power creation is highlighted by direct injection, air intake is all about the turbochargers. Two parallel turbos drive as much as 12 psi of boost into the intake manifold and dual-walled exhaust manifolds help drive more thermal energy back into the process. I pick up one of the manifolds, then a turbo, and fasten them together with two bolts. A plant worker would squirt a bit of silicone between the two flush surfaces, but because my engine's going to be torn back apart, we skip the sticky stuff. Eight bolts fasten the manifold to the engine block and I crank them down with an electric torque wrench just like the ones in the factory. Only in the factory, the tool records each and every bolt going on, automatically sets torque ratings for each, and records the whole process to prevent mistakes made by hangovers or a case of the Mondays.

Because the turbos help to drive up the engine's torque output, the traditional technique of using long intake runners isn't necessary, so the EcoBoost's manifold is noticeably shorter than its naturally aspirated counterpart. This prevents compression from happening in the intake and promotes higher compression inside the cylinders. It fits on top of the near-complete engine like a star on a Christmas tree.


Once the air and fuel finally meet in the EcoBoost's six cylinders, the engine produces 340 hp and 340 lb-ft of torque, but those figures might vary slightly from application to application. (The one I'm building? It'll probably make somewhere closer to 200 hp and drink oil like a worn-out RX-7.) Those numbers were also obtained on premium fuel — Ford recommends using the good stuff but assures us that the EcoBoost won't have detonation issues on regular unleaded.

Using direct injection allows the engine to run at a higher compression ratio of 10:1, which Shelby speculates is 0.75 to 1.0 points higher than the same turbo motor would run with conventional injectors. Along with the higher ratio, variable valve timing on the intake side provides increased efficiency and better low-end torque. By advancing intake timing as much as 40 degrees, Ford engineers were able to spread the engine's peak torque along a plateau from 1500 to 5000 rpm.

As I fasten one last bolt with the torque wrench, I can't help but be impressed by Ford's high-power V-6. It'll be marketed as an alternative to the company's own V-8s displacing 4.6 liters and higher, and Ford predicts fuel savings of as much as 20 percent. In products like the Flex, it'll boast a huge advantage over the less powerful sixes in GM's Lambda crossovers, Honda's Pilot, and others, while costing just $700 or so more than the current 3.5-liter. In another application, the EcoBoost will put the Lincoln MKS in a class above the twin-turbo BMW 535i, the Mercedes-Benz E350, or the Cadillac CTS and on par with some of our favorite V-8s, including Infiniti's M45. And then if Ford stuck this thing in an all-wheel drive Fusion — okay, we'll stop. But just keep this in mind: It was Ford's SVT communications manager who invited us out for a closer look at EcoBoost. Take from that what you will.

Of course, simply seeing and holding all the parts of this new engine in my hands isn't enough to say it'll draw Americans away from V-8s or more efficient foreign competitors. We'll have to wait until next spring, when the first Ford vehicles will start offering the EcoBoost, to say anything for sure.