The 1.0-litre Ecoboost - first introduced in 2012 - has a new single-piece camshaft module that has freed up space within the cylinder head for new oil channels and valve-switching componentry.
Ford engineers predict that the system will be active for a few seconds at a time in most driving scenarios and has the potential to improve fuel efficiency by up to 6%.
Installed in the current Fiesta, the 1.0-litre Ecoboost in 98bhp form is capable of a claimed combined economy of 65.7mpg, so a 6% improvement could take that figure to 69.6mpg.
Ford said it has “devised advanced solutions to counteract vibrations and ensure that cylinder deactivation is imperceptible to drivers in terms of operation and engine performance”.
The technology will be tested throughout 2017 and be made available for sale in 2018, although Ford hasn’t confirmed which car model will be the first to benefit from it. At present 11 Ford models – the Fiesta, Ecosport, B-Max, Focus, C-Max, Grand C Max, Tourneo and Transit Connect, Tourneo and Transit Courier and Mondeo – are available in Europe with the three-cylinder engine.
With the 1.0-litre Ecoboost available in three power ratings, Ford also has yet to confirm which of them will receive the cylinder deactivation technology.
The system uses an offset crankshaft configuration and deliberately ‘unbalanced’ flywheel and pulley that counteract vibration. The new dual-mass flywheel and a vibration-damping clutch disc help neutralise engine oscillations when the engine is running on two cylinders, especially at lower revs, and enable a wider operating range.
Intake and exhaust valves are closed when the system is active, trapping gases to provide a spring effect that helps balance forces across the three cylinders for refinement and also retain temperatures inside the cylinder that maintain fuel efficiency when reactivated.
New engine mounts, drive shafts and suspension bushes also will be specially tuned for refinement when the revised 1.0-litre Ecoboost is installed in a car.
The engine has also been made more durable to cope with the different loading forces resulting from cylinder deactivation, with uprated parts including a new camshaft chain, and valve rockers formed using advanced metal injection moulding.
The system was developed by Ford engineers in the UK, Germany and US, in collaboration with the Schaeffler Group, an engineering partner.
Bob Fascetti, Ford Motor Company’s global powertrain engineering boss said the engine was proof that "there is still untapped potential for even the best internal combustion engines to deliver better fuel efficiency for customers.”
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