There have been several rumors flying around as to the full details of Ford's new 1.5-liter Ecoboost engine.

The first of these relates to how many cylinders the new unit has. Ford's crypic press release didn't make this clear, with no menion of a cylinder count.

Road & Track however has heard through a reliable source that the 1.5-liter unit is not a three-cylinder, as suspected, but a four-cylinder unit.

The next rumor was to whether the U.S. would get a different unit to that debuting in China. In many markets outside the U.S. the Fusion is instead called Mondeo, and some suggested that the U.S. would get one 1.5-liter, and China another.

It isn't yet clear that North America will get the 1.5-liter Ecoboost engine, but if it does it's not likely to be a different engine from that on sale in China and other markets.

Ford originally chose the 'Mondeo' as a play on the latin word for "world", a car to be sold everywhere. Only now is that finally coming true and just like the Fiesta and Focus, the Fusion will be largely the same everywhere.

So rumors debunked, what purpose does the 1.5-liter unit serve?

For a start, it's expected to replace the existing 1.6-liter Ecoboost when it debuts in the 2014 Fusion. That's no bad thing, as the smaller engine still offers up 177 horsepower at 6,000 rpm, and a chunky 177 pounds-feet of torque from just 1,500 rpm, all the way to 4,500 rpm.

Efficiency is aided by an integrated intake manifold and water-cooled charge air cooler, and a clutch-controlled water pump to help speed up the warm-up cycle of the engine. Ford promises technology to help reduce noise, vibration and harshness too.

No efficiency details have yet been revealed, though it's reasonable to expect small improvements over the current 1.6-liter car--capable of 25 mpg city, 37 highway and 29 mpg combined in EPA testing, with the manual transmission.

Elsewhere the Mondeo won't differ too much from the Fusion sold in the U.S.--styling is largely the same, and equipment options like Ford MyKey and SYNC with MyFord Touch will remain.

We'll be sure to bring you the latest news if Ford does decide to offer its 1.5-liter Ecoboost in the U.S.


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