Adding a turbocharger gives the engine yet an extra boost.

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Toyota recently said it planned to boost production capacity for the 4-cylinder engine at the plant by more than 100, 000 units.

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Essentially leveraged as a form of high-tech turbocharging, here a small electric motor gives a modest fuel-free power boost to a direct-fuel-injected 2.4-liter four-cylinder engine.

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