Much of the auto industry is downsizing. Whilst makers turn to smaller capacity turbocharged engines offering greater efficiency and no performance penalty, Mazda North America has announced they won't be following suit.
Robert Davis, senior vice president of research, thinks it makes little sense to use turbochargers on smaller engines and that selecting the right size engine for the vehicle it will power is a better option.
Mazda do use turbochargers in some of their models - Mazdaspeed vehicles are turbocharged, as are the CX-7 and CX-9 crossovers - but in smaller applications they're not as relevant. "A 1.0L 3-cylinder turbo doesn't make sense to me", said Davis.
"Turbochargers are small, but complex,” he says. “They’re water- (or) oil-cooled, so I have to run lines from the radiator or the oil pump. Then I need an intercooler, and then I have to add the piping to go from the air intake to the turbo and the turbo back to the throttle body.”
This adds weight, complexity and expense and affects packaging, all of which can be a problem in smaller vehicles with less space under the hood and more of a sensitivity to changes in weight. There are also more issues, such as dissipating the heat of turbocharger components in a cramped engine bay and fitting an upgraded catalyst that can cope with higher temperatures.
This may come as a suprise to some, given that Mazda is a technology partner of Ford, who are stepping up their EcoBoost range of turbocharged gasoline engines which will be seen in both the Fiesta and Focus before too long. Davis says that whilst Mazda and Ford do share technology, the two makers will do separate directions with their powertrains.
Mazda claims its next generation range of engines, called 'Sky', could offer the economy of hybrid vehicles
. Technology such as direct injection, reduced friction components and optimal air-fuel mixtures to offer performance and economy and won't require turbochargers to do so, though turbos could still be used in larger applications, as today.