Ford’s EcoBoost Brings Higher MPG Without Sacrifice

Efficiency and luxury are not necessarily mutually exclusive. This concept was reinforced yet again when Green Car recently sampled some innovative 2010 Lincoln models powered by Ford Motor Company’s EcoBoost engine technology. Our experience showed that the marriage of high-tech engine downsizing with traditional luxury car amenities can indeed be a happy one, with Lincoln’s Ecoboost MKS sedans and new MKT crossover we were piloting delivering V-8 performance with V-6 economy as promised.

EcoBoost is Ford’s turbocharged direct injection technology that promises to do more with less. In the case of the Lincoln brand, a 3.5-liter EcoBoost V-6 produces power and performance very much on par with a larger displacement, less efficient V-8 powertrain. Lincoln’s 3.5-liter V-6 Ecoboost engine produces 355 horsepower at 5,700 rpm and, perhaps more importantly for these heavier luxury vehicles, 355 lbs-ft of torque. Boosted with sequential turbochargers, that diesel-like torque is available from a very low 1,500 rpm all the way up to 5,250 rpm, making the overall driving experience much more satisfying.

That wide-flat torque curve is important, because adding all the luxury appointments expected by Lincoln customers make these vehicles relatively heavy. The weight is noticeable with a naturally aspirated V-6 under the hood. With EcoBoost, even with luxury car bulk apparent while driving in a sporting manner, overall acceleration and performance is very V-8 like. Consider, too, that the EcoBoost V-6 also presents a lighter package than a V-8 powertrain, which helps keep overall mass down and aids vehicle dynamics. Lincoln has paired the 3.5-liter Ecoboost with an impressive electronic six-speed Select-Shift Automatic. The transmission can either be operated as a regular automatic or manually shifted with either the shift lever or wheel-mounted paddle shifters.

The EcoBoost magic comes from a combination of direct fuel injection and twin turbochargers. Fuel is sprayed directly into the combustion chamber on top of the pistons rather than being mixed with incoming air before entering each cylinder. The high-pressure direct injection cools the cylinder and allows a relatively high 10.0:1 compression ratio without the engine ‘knock’ (pre-detonation) that traditional turbo systems can induce. The twin turbochargers are water cooled for long life and feature electronically actuated wastegates that bleed off excess exhaust gas pressure for precise boost control. Because two small turbochargers are used instead of a single larger one, turbo lag – the hesitation between accelerator pressure and power delivery as an exhaust-driven turbine gets up to speed – is absent. EcoBoost also features variable camshaft timing to more accurately control intake and exhaust valves in the four-valve-per-cylinder design.

We like the fact that the 3.5-liter EcoBoost is such a flexible powertrain – it felt just as much at home in the larger platform MKS luxury sedan and as it did in the three-row MKT crossover. The MKT is based on the boxier Ford Flex. While the two share a common platform, though, there are no common exterior body panels or recognizable interior parts. The primary benefit of Ecoboost is improved fuel economy, which on average is 20 percent better than a like-powered larger displacement engine. That reduction in fuel use also nets a similar decrease in CO2 emissions, an important distinction since greenhouse gas reductions are a growing imperative these days.

So what kind of fuel economy can you expect? The Ecoboost MKS carries an EPA estimate of 17 mpg in the city and 25 mpg on the highway. The 7-pasenger MKT all wheel-drive crossover, with a base curb weight of 4,924 lbs, delivers EPA estimates of 16 mpg in the city and 22 mpg on the highway. Our drive in early production units around the San Francisco Bay Area showed these EPA figures to mimic real world driving economy, though we were able to easily beat those numbers with efficient driving techniques. EcoBoost is the real deal.