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Mazda Launches New Demio; Up to 20% More Fuel Efficient Than Predecessor

The new Demio (Mazda2).

Mazda Motor Corporation announced the Japanese launch of the fully redesigned Mazda Demio (known overseas as the Mazda2). As of May 2007, the Demio family, first introduced in 1996, had a total production volume in Japan of more than 1,040,000 units and had become Mazda’s biggest selling model in the Japanese market.

At the launch event, Mazda President Hisakazu Imaki said that the automaker is considering launching a new model that would be smaller than the Demio, which is currently the smallest vehicle in the company’s lineup.

With a completely redesigned body and chassis, the new Demio is around 100 kilograms lighter than the previous model. The Demio 13C-V grade combines Mazda’s newly developed, naturally aspirated MZR 1.3L Miller-cycle engine with continuously variable transmission (CVT) to achieve 10-15 mode fuel efficiency of 23.0 km/L (4.35 l/100km or 54 mpg US). This represents an improvement of approximately 20% over the previous Demio model.

Newly developed from the current MZR 1.3L DOHC aluminum engine, the Miller-cycle variant 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 1.3L engine when cruising and accelerating.

The Demio also offers conventional 1.3L and 1.5L engine options as well. All model grades offer emissions at least 75% lower than Japan’s 2005 standards.

The new Demio marks Mazda’s first use of a CVT—in both the 13C-V and two 1.5L models. For the CVT used in the 1.5L SPORT grade, a seven-speed manual mode is included that enables the driver to shift up and down using steering wheel-mounted paddle shifters.

The Demio is also the first car produced by Mazda which has electric power-assisted steering built into the steering column. The amount of assistance varies depending on vehicle speed and driving conditions to enhance the driver’s connection to the car. This technology also improves the Mazda-unique driving feel and contributes to better fuel consumption, whether maneuvering at low speeds or cruising on the highway.

After a full chassis design review, the use of 980 MPa-grade ultra-high-tensile steel and high-tensile steel was increased in order to enhance body rigidity and safety levels. Strengthening the sheet steel welds in the door and tailgate frames further improved the body local rigidity and allowed further weight reduction.

The all-new Demio has outstanding aerodynamic characteristics with a drag coefficient of 0.32, which contributes to its improved fuel efficiency.

To reduce the concentration of volatile organic compounds (VOC), the Mazda Demio employs low-VOC emitting resins, paints, and adhesives in the cabin. It satisfies the indoor VOC concentration level guideline figures for 13 substances that were set by Japan’s Ministry of Health, Labor and Welfare.

New Demio Engine Options
Miller Cycle
Displacement [cc] 1,348 1,498
Max. power
67/90 66/89 83/111
Max. torque
124/91 120/89 140/103
10-15 fuel econ.
21.0 23.0 CVT: 20.0
5MT: 19.4
Equiv. fuel Cons.
4.76 4.3 CVT: 5.0
5MT: 5.2
Equiv. Fuel econ.
[mpg US]
49.4 54.0 CVT: 47.0
5MT: 45.6



That's the solution : efficient engine technologies, efficient body technologies (highstraingth steel, aluminum, and so on) used to produce a lighter car.

The growth (of weight, size, equipment, power...) is a non-sense!


The quoted aerodynamic Cd of 0.32 doesn't sound "outstanding" to me.

For a small car, think Daihatsu UFE for 0.16-0.19 Cd.

Bud Johns

Clett, the UFE pulls .025, which is fantastic. I agree the mazda's numbers aren't anything to get exited about, but I suspect it will be used primarily for city driving. The Prius pulls .026, by the way. In any case, the mazda is a great city car.

Bud Johns

Okay, move my decimal point one to the right please.....

Tim Russell

"The quoted aerodynamic Cd of 0.32 doesn't sound "outstanding" to me."

Nor me, looking at the picture of the car I think that must be a mis-print. It just looks more areodynamic. I'll watch for other articles on the car to see if they use the same number.


Cd 0.19 for the 4-seater, 0.168 for the 3-seater:

(and 170 mpg US)

Bud Johns

Sorry, Clett, I did more research and apparently you were correct. I originally went to this site:
But the rest I went to listed your figures. Is this car in production?? In any case, that is unheard of aerodynamics......

Bike Commuter Dude

I thought that Miller-cycle engines needed to be forced induction, but this one is reportedly naturally aspirated. Can anyone explain?

Bike Commuter Dude

I thought that Miller-cycle engines needed to be forced induction, but this one is reportedly naturally aspirated. Can anyone explain?


The UFE looks like the Honda Insight my wife has.


Bike Commuter Dude,

I see what you mean. A normally-aspirated version would normally be called an Atkinson-cycle engine, instead of a Miller-cycle engine.

It would seem that there a little bit of confusion as to which SHOULD be called which.

According to that, the original Atkinson-cycle engine had a complex crank mechanism which result in different compression and expansion ratios. Miller hit upon the idea of delaying the intake valve closing. This may be why they're calling it a Miller-cycle engine.

Bud Johns

It's simply late exhaust valve closing, like on the Prius. This allows a static compression ratio of 13 to 1 in the case of the Prius, but in reality it gets about 9.5 to one. BUT, the expasion ratio remains 13 to 1, which allows that much more heat to be harnessed as energy. These engines are not good for torque, but the Prius compensates with 295 lb ft at 0 rpm up. This car's CVT helps compensate for that by running at optimum rpm for any given condition........

Bud Johns

Sorry, the Prius electric motor delivers the aforementioned torque..........


About the Cd of .32 - as long as you stick with the conventional car layout (4 wheels, side-by-side seating, etc.) it gets increasingly harder to have low Cd ratings in increasingly smaller cars. Example; If all other dimensions were the same a longer 4 seater car would have a better Cd than a 2 seater car. However aerodynamics isn't just the Cd, its also the frontal area, which does decrease in smaller cars. Multiplying Cd by the car's frontal area gives an index of total drag. The result is called Drag Area.


Replace that Atkinson cycle engine with a turbo CI engine and add hydraulic launch assist. They would get 20% better fuel economy and not require any of that useless battery nonsense.


I think it's likely we'll see the Mazda2 here in the USA within 18 months. Because the EPA is seriously looking at EU specification fuel economy ratings based on CO2 output, that could encourage Mazda to sell the Mazda2 here. The vehicle will likely be assembled at Ford's Hermosillo, Mexico plant alongside the next-generation Ford Fiesta, which uses the same platform. The US version of the Mazda2 will use the ZY-VE engine with either the 5MT or CVT transmissions.

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