We've driven it in the Focus. We're going to get it in the Fiesta. We've even seen it attacking one of the world's meanest race tracks.

It is of course Ford's 1.0-liter, three-cylinder EcoBoost engine, a tiny turbocharged unit aiming to match the performance of a naturally-aspirated 1.6-liter, with the efficiency of something much smaller.

U.S. buyers aren't really used to truly small engines, so what they'd make of the new EcoBoost in the Ford Mondeo--Europe's version of the Ford Fusion--is anyone's guess.

The company has announced that the Mondeo, which goes on sale in Europe next year, will be equipped with the 123-horsepower fuel-sipping motor, making it comfortably the smallest engine Ford has ever put in a car of that size.

It isn't unknown in European countries to put smaller engines in larger cars--several generations of Mondeo have used 1.6-liter engines, albeit when cars were a little less lardy than they are today.

But even for consumers used this, the small engine, large car combination may take a little getting used to.

Not that it's harmed sales of the 1.0-liter Focus, which currently makes up a quarter of sales in the U.K. market. And provided the EPA economy numbers are impressive, U.S. buyers should have no problem taking to the engine in the Fiesta.

However, it's extremely unlikely we'll see it in the 2013 Ford Fusion, the Mondeo's global cousin--not only would U.S. buyers likely be suspicious of such a small engine in a midsize car, but cars like the Fusion Hybrid and Energi will serve the needs of eco-minded buyers--two variants unlikely to be sold in Europe.

Would you buy a Fusion with Ford's littlest EcoBoost, provided the price was right? Or would it be just a step too far? Leave us your thoughts in the comments section below.


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