It's been rumored for a while that the next-generation Chevy Volt electric car would get a new, smaller, three-cylinder engine as a range extender.

Now we've seen what that engine could be, in the guise of a 1.0-liter turbocharged three-cylinder engine unveiled by GM's German arm, Opel, at this week's Frankfurt Auto Show.

The Opel Monza Concept that debuted in Frankfurt may point the way to the first major update of the Voltec range-extended electric powertrain, which will likely be launched in 2016 or so.

The Monza concept is a sporty shooting brake with gullwing doors that takes its name from Opel coupes of the Seventies and Eighties.

Opel Monza concept, 2013 Frankfurt Auto Show

Opel Monza concept, 2013 Frankfurt Auto Show

While Opels all but vanished from the U.S. market more than 30 years ago, the German brand and its British Vauxhall equivalent remain GM's largest in Europe.

Its 115-horsepower turbocharged 1.0-liter three-cylinder engine is the first in a new series of direct-injected gasoline engines that will appear not only in Opels but in other General Motors vehicles globally.

Future range extender

If the next Volt follows the powertrain strategy of the current model launched for 2011, its gasoline range extender may be an adaptation of a turbocharged engine used in various gasoline cars--but with its turbo removed.

The current Volt engine is a 1.4-liter four that produces 85 hp, adapted from the 138-hp 1.4-liter turbo fitted to the Chevrolet Sonic subcompact and Cruze compact sedan.

Opel gave very few specifics on the powertrain in the Monza Concept, aside from noting that the turbo 1.0-liter three in this case was powered by natural gas, which would further reduce its carbon emissions compared to running the same engine on gasoline.

In March, Edmunds reported that GM was considering a smaller, three-cylinder engine for a revised Volt to be released in 2016--though at that time, the substitution had not been officially approved.

GM's Opel 1.0-liter SIDI turbocharged three-cylinder engine - 2013 Frankfurt Auto Show

GM's Opel 1.0-liter SIDI turbocharged three-cylinder engine - 2013 Frankfurt Auto Show

More torque, more refined

The engine block of the new 1.0-liter turbo three is entirely aluminum, reducing weight.

Nonetheless, GM expects the new three to be more refined than than the naturally-aspirated 1.6-liter fours it will replace--along with more torque and 20 percent better fuel efficiency.

"We not only set out to minimize fuel consumption and CO2 emissions," said Matthias Alt, who's chief engineer for small gasoline engines at Opel. "We also wanted to demonstrate that three cylinders can be just as refined as four or more."

"We’re confident customers will be pleasantly surprised by the results," Alt continued. "This is a very lively and refined three-cylinder engine [that] doesn’t compromise on driving fun.”

One of many new engines

As well as direct injection and variable timing for all 12 valves, the exhaust manifold is integrated into the engine head as a single casting, reducing parts count and making the engine more compact.

The new three-cylinder engine is the second of several new engines and powertrains that will be launched by GM over the next few years. The first was a new 1.6-liter turbodiesel.

2013 Opel Adam

2013 Opel Adam

Allied to a new six-speed manual gearbox, the 1.0-liter turbo three will be launched first in the Opel Adam minicar sometime next year.

It might also replace the current 1.2-liter four-cylinder engine used in the U.S. version of the Chevrolet Spark minicar built in Korea.

BMW, Ford, MINI, Mitsubishi, more

Meanwhile, more and more three-cylinder engines are being launched or added by major automakers.

BMW will the use its 1.5-liter three in not only the 2015 BMW i8 plug-in hybrid sports coupe, but also a wide range of next-generation MINI and small BMW vehicles to come. We test-drove a prototype of that engine earlier this year.

Ford said 10 days ago that it would double production of its own three-cylinder engine, the turbocharged 1.0-liter EcoBoost powerplant that will be offered in the 2014 Ford Fiesta subcompact.

We've driven a three-cylinder Fiesta prototype too.

And the upcoming 2014 Mitsubishi Mirage subcompact is offered with a 74-hp 1.2-liter three, without a turbocharger.


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