Ford Fiesta pops along on three cylinders

A three-cylinder engine may not sound like much, but it proves plenty for the new Ford Fiesta SFE.

Wayne Cunningham Managing Editor / Roadshow
Wayne Cunningham reviews cars and writes about automotive technology for CNET's Roadshow. Prior to the automotive beat, he covered spyware, Web building technologies, and computer hardware. He began covering technology and the Web in 1994 as an editor of The Net magazine.
Wayne Cunningham
3 min read
2014 Ford Fiesta SFE Ecoboost
Josh Miller/CNET
2014 Ford Fiesta SFE EcoBoost
Ford is adding the SFE EcoBoost as a trim variant of the Fiesta subcompact car. Josh Miller/CNET

LOS ANGELES -- In a review of the 2014 Ford Fiesta earlier this month, I suggested waiting for the EcoBoost version, which Ford has promised will be available in just a month or two. At the Los Angeles Auto Show, I proved myself right when Ford gave me a chance to drive a 2014 Fiesta SFE with the EcoBoost engine.

This engine is a story unto itself, in that it is a lot smaller, but a lot more powerful, than the Fiesta's current engine.

Under the hood of a current generation Fiesta, you will find a fuel efficient, but not very powerful, 1.6-liter four cylinder engine. The EcoBoost engine in the Fiesta I drove only has three cylinders displacing 1-liter, or 999 cc to be technical. Yet despite its smaller size and one less cylinder, the EcoBoost engine produces 123 horsepower -- that's three more than the 1.6-liter engine. The bigger difference comes in torque, where the EcoBoost engine creates 148 pound-feet versus 120 from the larger engine.

2014 Ford Fiesta SFE EcoBoost
This three-cylinder engine measures less than a foot across. Josh Miller/CNET

Ford's one-liter engine pulls off this seeming miracle through pure technology. Direct injectors spray fuel into the cylinders, where it mixes with air and combusts in a very complete burn. A small turbocharger -- a Ford spokesperson said the impeller is only 1.5 inches wide -- forces air into the cylinders at pressure, which leads to more power. The valves are timed for different engine speeds and conditions, creating optimum intake and exhaust cycles.

But a turbo can also cause power lag and surges.

Getting behind the wheel of the Fiesta SFE with the EcoBoost engine, I put the five-speed manual transmission into gear and hit the gas. Even with two other passengers, the car took off with quick acceleration. That 148 pound-feet of torque launched the Fiesta far better than the 1.6-liter engine had in the earlier example I had driven.

When I shifted up, however, the power lagged, with little response to the gas pedal. That power drop had more to do with the transmission than the engine, as the second gear ratio was taller than I expected. Dropping back to first, I let the engine wind up until the car was at higher speed, then upshifted. There was a little learning curve for the gearing.

During a half-hour drive, I ran the Fiesta SFE EcoBoost up a freeway on-ramp, accelerating for a traffic merge. I took it through all its gears, finding that I could drop down to third when I needed power at freeway speeds. I shot through Los Angeles traffic, finding the right gears to skip through lanes, the little one-liter engine giving plenty of thrust for each maneuver.

2014 Ford Fiesta SFE EcoBoost
The SFE trim Fiesta can be had with the EcoBoost engine option. Josh Miller/CNET

An aggressive growl emanated from the engine compartment when I wound it up, but Ford had obviously spent some time insulating the cabin from the noise, as the sound was pleasantly muffled. I didn't feel any vibration from the engine, other than what I would expect.

Of course, the fact that I was driving the manual transmission version of the car gave me good control over the power, letting me wind up the engine when I wanted all it had to give. The car will be available with an automatic transmission, which will behave very differently.

With the manual transmission, the EcoBoost engine gets the Fiesta an EPA-rated 32 mpg city and 45 mpg highway, that latter number the highest of any pure gasoline car on the market. It's an impressive feat for something that responded so well.

Ford should have this new Fiesta in showrooms within a couple of months. It will show up as the Fiesta SFE model, with the EcoBoost engine as a $1,000 option. In SFE trim, the Fiesta also features a few aerodynamic upgrades and low rolling resistance tires.