Mazda against turbocharging downsized engines to meet mpg goals

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As automakers scramble to meet looming fuel economy standards, turbocharging downsized gasoline engines has gained popularity in the automotive industry. By adding a turbo to a low-displacement mill, vehicles equipped in this way often return decent fuel economy numbers without sacrificing performance. However, Mazda claims the strategy is flawed.

Robert Davis, Mazda's senior vice president of research, development and quality, isn't crazy about the idea of slapping a turbo on a downsized engine. As Davis told Ward's Auto:

When you take a vehicle like the CX-9, it has space for a large displacement four-cylinder [engine] and a turbo. But a 1.0-liter three-cylinder turbo [engine] doesn't make sense to me.

Davis insists that turbochargers can add complexity, cost, a slew of packaging issues and unnecessary weight to a vehicle, stating:

Turbochargers are small, but complex. 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.

And then you need to get the air out, so you need an evacuator. If I have a turbo right next to a catalyst, then I need a different catalyst material because a turbo retains so much more heat and a catalyst won't live as long.

Furthermore, Davis claims that it's more desirable to ditch the turbo and instead equip a vehicle with an engine that sized correctly for the application, stating:

A turbo and downsizing is a temporary solution to not having the right engine in the car in the first place. Anytime you add a turbo to the system, it's fundamentally less efficient because of the drag and the motion and the weight and everything that's associated with it.

However, Mazda does offer turbocharged models, which, at least to some degree, implies that the technology has advantages too... zoom zoom indeed.