While other manufacturers have turned to turbocharging and hybrids to boost fuel economy, Mazda has tried to squeeze the most it can out of unassisted internal-combustion engines.

The company's SkyActiv line of efficiency-focused engines rely solely on tuning and some technical tricks to maximize gas mileage.

SkyActiv engines have largely lived up to Mazda's claims in the real world, and they could soon get even more efficient.

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Mazda expects to improve fuel efficiency for the next generation of SkyActiv engines by 30 percent, according to company president Masamichi Kogai in an interview with Auto Express at the recent Frankfurt Motor Show.

These new engines should appear by 2018, and will likely represent the main component of Mazda's fuel-efficiency strategy.

The carmaker is among the smallest in the industry, and has used SkyActiv as a way to boost efficiency without the greater investment that would be required by electrified powertrains.

2015 Mazda CX-5 GT

2015 Mazda CX-5 GT

Mazda isn't completely ignoring that option, though.

Kogai also said that Mazda is gauging customer interest in hybrid and electric cars in its home market of Japan.

He also noted that the company has a team of "specialists" investigating whether it would be feasible to revive the rotary engines that were once a Mazda signature.

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Nothing more substantial than hints like these was officially discussed by Mazda at Frankfurt.

The Japanese carmaker used the show to debut its Koeru concept, a crossover intended to showcase possible design directions for future production models.

Mazda currently offers SkyActiv gasoline engines only in the U.S., and gasoline and diesel versions in other markets.

2015 Mazda 3

2015 Mazda 3

The company has promised to bring a diesel engine to the U.S., but it seems to have slipped down the list of priorities.

Officials have said that getting the engine--a 2.2-liter four-cylinder--to meet U.S. emissions standards might sacrifice performance.

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Mazda views a sporty character as important to its brand identity.

New versions of the Mazda 2 subcompact and CX-9 crossover are expected in the near future, but it's unclear whether they will feature the updated SkyActiv engines.


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