- Car shoppers will have more choices in the future when it comes to fuel-efficient vehicles with three-cylinder engines.
- Automakers are developing high-tech three-cylinder engines that are turbocharged, quiet, powerful and fuel-efficient.
- Ford, Mini, Mitsubishi and Smart are onboard with this trend, with others to follow this decade.
DETROIT — Car shoppers will have more choices in the future when it comes to fuel-efficient vehicles with three-cylinder engines.
The drawbacks associated with these small power plants decades ago have been resolved.
Automakers are developing small, high-tech engines because they need to balance their model lines. Specifically, they require small, high-mileage cars so they can sell a wide range of bigger, more expensive, more profitable but less fuel-efficient cars, SUVs and pickup trucks.
Today, the 2014 Ford Fiesta, Mini Cooper, Mitsubishi Mirage and Smart ForTwo are the only three-cylinder models available in the United States. But the three-cylinder offerings will expand this decade.
"The push to meet strict new CAFE standards has forced manufacturers to introduce smaller vehicles, and thus smaller power plants," said Jonathan Mandanici, data research associate at Edmunds.
"These new three-cylinder engines can compete with current- and previous-generation four-cylinder engines in terms of power and refinement, while still consuming less fuel," he said. "These are very desirable attributes in the current automotive market where a shopper's focus has shifted towards high mpg figures in the wake of recent spikes in fuel prices."
Diesel engines and electric, plug-in hybrid and conventional hybrid technology are not enough to boost an automaker's fuel economy to meet federal regulations this decade and next. Basically, automakers need a little bit of everything, especially at the low end where buyers are price-sensitive. A three-cylinder engine is the answer because it also can be adapted to other technologies.
"The smaller displacement (engine) may perform solo" in some entry-level models "or used in concert with an electric motor in hybrid vehicles," Michelle Culver, a spokeswoman for IHS Automotive, a research firm, told Edmunds.
Decades ago, three-cylinder engines were offered in such budget econoboxes as the Geo Metro and Subaru Justy. While each sipped fuel, which translated to high mpg, the engines were noisy and underpowered, resulting in agonizingly slow performance.
Today's three-cylinder engines are smooth, quiet and powerful. Some, such as the ones in the Fiesta and Mini Cooper, are equipped with a turbocharger to boost performance.
"The obvious advantage is better fuel economy and the obvious disadvantage is reduced horsepower," Culver said. "In some cases the power may be inappropriate because the vehicle may be too heavy. The vehicle may have originally been designed for a four-cylinder engine.
"However, it is also possible that the three-cylinder powertrain can have technology such as EcoBoost (turbocharging) that gives it the same power as a four. So, the power is not always less than that of a four. It has to be looked at on a case-by-case basis."
Fuel economy is the main incentive for buyers. For example, the 1.0-liter three-cylinder Fiesta EcoBoost is EPA rated at 36 mpg combined (31 city/43 highway) with a manual transmission. The three-cylinder engine is part of an optional $995 fuel economy package. An automatic transmission is not offered with the three-cylinder engine. The standard 1.6-liter four-cylinder Fiesta is rated at 31 mpg combined (28 city/36 highway) with a manual.
As for the other models, the 1.5-liter Mini Cooper is rated at 34 mpg combined (30 city/42 highway) and the 1.0-liter Smart ForTwo, 36 mpg combined (34 city/38 highway). Both models use premium fuel. The 1.2-liter Mitsubishi Mirage is rated at 37 mpg combined (34 city/42 highway).
Yet, despite the fuel economy benefits, three-cylinder cars are off to a slow sales start. The cars are expected to grab less than 1 percent of the vehicle market this year, Culver said.
According to IHS Automotive, which tracks vehicle registrations, 8,165 of these vehicles ended up in the hands of consumers through April. The leader was the Mirage, 5,272, followed by Smart ForTwo, 2,009; Fiesta, 454, and the Mini Cooper, 430. But their popularity is expected to grow as more models are introduced.
"We're forecasting approximately 4 percent by 2020," Culver said.
Mandanici expects an unnamed Volkswagen model, a 2015 Ford Focus model and a BMW 1 Series hatchback with a 1.5-liter turbocharged engine to be added this decade. Analysts have said General Motors is considering a three-cylinder engine in the face-lifted 2016 Chevrolet Volt and 2017 Cadillac ELR.
GM spokesman Tom Read would not reveal the automaker's U.S. plans. Three-cylinder engines are offered in other regions of the world, however.
"We'll continue to evaluate when and where the Ecotec three-cylinder engine fits" in terms of fuel economy and vehicle performance, Read said.
BMW spokesman Dave Buchko said the automaker is moving in that direction but that the only car on the immediate horizon for the United States is the upcoming i8 plug-in hybrid sports car. The new 2 Series Active Tourer will be equipped with a three-cylinder engine, but whether the car will be sold in the United States is undecided, he said.
"As part of our broader BMW EfficientDynamics initiative we have been moving progressively from normally aspirated engines to smaller-displacement turbocharged engines with fewer cylinders," Buchko said. "A turbocharged three-cylinder, then, becomes a natural replacement for a normally aspirated four-cylinder."
Culver is optimistic about consumer acceptance this decade.
"Like we have already seen with downsizing from an eight-cylinder to six or six-cylinder to four, consumers appear to be satisfied as long as the engine performs as well as the (larger) displacement that it is replacing," she said.
Edmunds says: As long as cars are fuel-efficient and fun to drive, buyers likely won't care what's under the hood.