Hybrid and diesel might be winning the gas mileage wars, but gasoline is stepping up its game.

We'll shortly see the debut of two new gasoline-powered models that offer the highest non-hybrid gasoline-fueled gas mileage on the market--the 2014 Ford Fiesta 1.0 Ecoboost, and the 2014 Mitsubishi Mirage.

Both go about achieving that claim in slightly different ways, but there are similarities too.

Each has three cylinders, for a start. Dropping a cylinder from the usual four is a popular way of improving gas mileage in a small capacity engine, by reducing internal friction compared to an equivalent four-cylinder.

We've not seen many other threes on the market before. The highest-profile are the current Smart Fortwo, and the old Geo Metro.

The Fiesta and Mirage make the concept more appealing though, with modern standards of safety and equipment. But there the cars start to diverge.

Ford's Fiesta Ecoboost goes about its business with a 1.0-liter, turbocharged engine. For a 1.0 its power output is quite healthy as a result--123 horsepower. It's enough to pull the relatively lightweight Fiesta along at a decent pace, and the engine is also surprisingly refined.

Refinement isn't one of the Mirage's greatest qualities, as we found when testing a European-spec version in the UK.

Its naturally-aspirated 1.2-liter unit isn't overly powerful, unable to break the 80-hp mark, but with a low curb weight and slick aerodynamics it'll still get up to speed if you work it hard enough.

It doesn't handle as nicely as the Fiesta either, though few small cars do--Ford has nailed the fun factor in its smallest offering. With light controls and a spacious cabin the Japanese car might appeal to the more practical-minded driver, though.

2014 Ford Fiesta 5-door hatchback

2014 Ford Fiesta 5-door hatchback

The Ford's great unknown is fuel efficiency. The company is claiming best-on-the-market gas mileage, but Mitsubishi's figures of 37 mpg city, 44 highway and 40 combined, the CVT-equipped Mirage has already staked a claim to that title. The manual transmission version should be pretty frugal too.

Unless Ford has forgotten about the Mitsubishi, that could mean combined gas mileage of 40 mpg or more, and impressive highway numbers too.

Which do you think will win, and which car will really appeal to eco-conscious drivers? Leave your thoughts below.


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