Jalopnik
green tea for the millerman
Mazda Goes Miller Cycle With Demio for Japan
Watch out, diesel. Mazda says it's developed a Miller-cycle engine for the new Demio (Mazda2) in Japan that gets around 54 miles per gallon. The new JDM gas sipper goes on sale in July, sporting a 20 percent improvement in mileage over the current model, in combination with a continuously variable transmission. So what's this Miller cycle we speak of? Let's ask Wikipedia:"In the Miller cycle, the intake valve is left open longer than it would be in an Otto cycle engine. In effect, the compression stroke is two discrete cycles: the initial portion when the intake valve is open and final portion when the intake valve is closed. This two-stage intake stroke creates the so called "fifth" cycle that the Miller cycle introduces. As the piston initially moves upwards in what is traditionally the compression stroke, the charge is partially expelled back out the still-open intake valve."That's lovely. Problem is, the engines trade power for efficiency, which is usually compensated with a supercharger or electric motor (in the case of hybrids). Mazda's new Miller is naturally aspirated. Maybe the whole Zoom-Zoom thing accounts not stopping for gas. It's more of a net benefit thing.
More »
