Mazda Roadster 20th anniversary editionEnlarge Photo
Mazda has flipped-flopped a lot on its powertrain strategies in the recent past, at one point ruling out gasoline-electric hybrid vehicles in favor of clean-diesels and then quickly reversing that decision. Now the company has announced that it will introduce a more fuel-efficient powertrains by 2011 as its latest effort to reach its goal of increasing fuel economy across its model line 30% by 2015.
The new powertrains will include both four-cylinder and rotary engines, with some units expected to achieve fuel economy better than 42 mpg on the highway. The information comes from Mazda R&D chief Seita Kanai who said a redesign of the company’s best-selling 2.0-liter four-cylinder engine with a new six-speed automatic transmission will see city fuel economy increase to 32 mpg from 22. Highway fuel economy would increase to 42 mpg from 32.
The fuel economy gains are expected to come from more direct-injection technology, improved combustion, more efficient transmissions, engine stop-start systems, regenerative brakes, a high-pressure fuel pump and variable intake and exhaust valve timing.
Other details are scarce, but Kanai’s North American equivalent, Robert Davis, said the new powertrains cannot be retrofitted to an existing product line. However, the new powertrains are expected to feature across Mazda’s entire product line by 2015, with the MX-5 (Miata) most likely to be the first recipient.
Of most interest is the next-generation of Mazda’s rotary technology. The company is currently working on a new 1.6-liter twin-rotor design that is said to be more than 30% more efficient than the current unit found in the RX-8 sports car.
Finally, Mazda wants to bring its newer-generation clean-diesel models to the U.S., though first the cars have to be engineered to work with automatic transmissions--a necessity for this market.
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