Owners of some larger engined cars are familiar with their engines’ computer controlled cylinder deactivation, but Ford has now readied the feature for its award-winning 1.0-litre turbocharged 3-cylinder engine.
Already one of the world’s most fuel-efficient gasoline engine, the 1.0 Ecoboost will further improve its economy and emissions in 2018 as the world’s first 3-cylinder engine to benefit from cylinder deactivation, defying conventional thinking.
“Ford has pushed back the boundaries of powertrain engineering once again to further improve the acclaimed 1.0-litre Ecoboost engine, and prove that there is still untapped potential for even the best internal combustion engines to deliver better fuel efficiency,” said Bob Fascetti, vice president, Global Powertrain Engineering, Ford Motor Company.
The procedure will disengage, and re-engage, fuel delivery and valve actuation to one of the engine’s cylinders in the blink of an eye (actually about 20 times faster, at 14 milliseconds), when the engine load is light (such as during highway cruising or when coasting down a long hill).
However, that’s not as easy to do in an inline engine as it is for an engine with multiple banks of cylinders, which have natural balancing abilities by their very design. So, the 1.0 “three” has advanced engineering solutions to counter vibrations (which usually take into account all cylinders firing, but need to adjust to a “sleeper”), such as off-setting the camshaft and actually unbalancing the flywheel.
The engine uses a new dual-mass flywheel and a clutch disc specially formulated to dampen vibrations. The deactivated cylinder also traps the fuel air mixture in the combustion chamber to provide a “spring” effect for the piston (usually the explosion of the gasses forces the piston downward). The trapped gasses also help modulate engine temperatures in the cylinder to aid fuel-efficiency when then the cylinder is reactivated.
Other new components include engine mounts, drive shafts, suspension bushings, camshaft chain and valve rockers
The cylinder deactivation system uses engine oil pressure to activate a special valve rocker that interrupts the connection between the camshaft and the valves to the first cylinder. Working at engine speeds up to 4500 rpm, it’s all controlled by software that determines when to deactivate the cylinder based on factors like engine speed, throttle position and engine load.
“With the variable capacity delivered by cylinder deactivation, drivers get the power and performance of the whole engine when they need it, and the enhanced fuel efficiency of a smaller engine when they don’t,” said Denis Gorman, powertrain engineer, Ford of Europe. “Our research shows that in most driving scenarios the system will be active for just a few seconds at a time, making fast and seamless operation crucial, and has the potential to improve fuel efficiency by up to 6%.”
The system took a team effort to develop, with Ford engineers in England, Germany and the US working with Ford partner Schaeffler Group.