- Published in Features.
When Ford thinks consumers in its domestic market will trade big V8 gasoline engines for V6s then you know that downsizing really has caught on everywhere. For sure, this particular V6 is still a 3.5-litre and is boosted by a pair of turbochargers, but this still counts as progress.
Now there’s also a 2-litre Ecoboost engine which will be used in the US to replace naturally aspirated V6s between 2.5 and 3.5 litres. Applications will include the Explorer and Edge SUVs. In Europe it will replace 2.3-litre four-cylinder and 2.5-litre five-cylinder turbocharged engines.
The latter is currently the top engine option in the large Galaxy and S-Max MPVs and D-segment Mondeo sedan, as well as the outgoing Focus ST and RS C-segment hot hatches. Ford’s design targets for the 2-litre Ecoboost engine were simple.
“It had to be much more efficient than the gasoline engines it replaces, mainly through downsizing and downspeeding, but it still has to provide fun to drive for the consumer,” said Dr Thomas Zenner, Ford’s supervisor for the 2.0 Ecoboost engine. “So we need high torque output and excellent response behaviour. And it has to offer very good NVH.”
Cost was also critical, especially for US applications: it would be difficult to explain to consumers there why they should pay more for an engine with fewer cylinders.
Also important for the US was the ability to run on 91 octane gasoline.
The starting point was the 2-litre Duratec engine, developed with Mazda. This unit has already been optimised for low friction, said Zenner, and was therefore an excellent basis for further development.
The basic architecture, including bore pitch, bore and stroke, was carried over into the 2.0 for maximum commonality and minimum tooling investment at the Valencia plant in Spain. Block height is shared with the 2.3.
The aluminium cylinder head is completely new. It features dual cam-phasing with 50° operating angle, enabling a range of valve timing strategies to be used, including late intake valve opening for high internal exhaust gas recirculation at part-load, and late intake valve closing for Atkinson cycle operation for maximum thermal efficiency.