Mazda Develops New Naturally-Aspirated MZR 1.3-liter Miller-cycle Engine; 20% Improvement in Fuel Economy
|The new engine will power the new Mazda2 (Demio).|
Mazda Motor Corporation has developed a new, naturally aspirated MZR 1.3-liter Miller-cycle gasoline engine, which will power the all-new Demio (Mazda2 in non-Japanese markets) when it goes on sale in Japan in July 2007.
In combination with Mazda’s first continuously variable transmission (CVT), the engine enables the new Demio to offer a 10-15 mode fuel economy of 23.0 km/liter (4.3 l/100km or 54 mpg US), an improvement of approximately 20% over the 19.2 km/liter (5.2 l/100km, 45 mpg US) rating of the current 1.3-liter engine model.
Newly developed from the current MZR 1.3-liter DOHC aluminum engine, the naturally-aspirated MZR 1.3-liter Miller-cycle engine employs delayed closing of the intake valves in order to reduce pumping losses and improve thermal efficiency through a higher expansion ratio.
Intake valve timing is optimized by the Sequential Valve Timing System to provide improved fuel efficiency over the current MZR 1.3-liter engine when cruising and accelerating. In conjunction with the CVT, which transfers torque at low speeds without power loss and eliminates gear-shift shock, the setup achieves excellent fuel efficiency as well as good ride dynamics.
In addition to the new powertrain, the all-new Demio has been made approximately 100 kg lighter than its predecessor through weight reduction techniques, which have resulted in nimble handling and support for the significantly improved fuel economy.
The Demio model with the naturally aspirated MZR 1.3-liter Miller-cycle engine combined with the CVT transmission achieves a fuel economy that is rated as 20% or better than the level specified by Japan’s 2010 fuel economy standards. Exhaust emissions are also at least 75% lower than 2005 standards, which conforms to Japan’s Super Ultra-Low Emissions Vehicle (SU-LEV) standard and qualifies the Demio for Green Tax exemptions.
Separately, the day prior to the announcement of the new 1.3-liter engine, Mazda had celebrated the 40th anniversary of its first rotary engine. As of the end of April 2007, Mazda has manufactured approximately 1,970,000 rotary vehicles since production first began.