Many cars, including the Mazda CX-5 and Volkswagen Golf, use variable valve timing to maximize fuel efficiency and performance.

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Silverado and Sierra will accomplish its new mileage pinnacle with a 5.3L EcoTec3 V-8 relying on direct injection, cylinder deactivation and variable-valve timing to achieve EPA estimates of 16 mpg in the city and 23 mpg on the highway with two-wheel drive, or 16 in the city and 22 on the highway with four-wheel drive.

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