Valve timing is a major factor in achieving good volumetric efficiency.

定时阀是实现高容积效率的一个主要因素。

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The 4-cylinder is a 16-valve DOHC design with Toyota’s VVT-i variable cam timing system, and is rated at 179 horsepower at 6000 rpm and 172 lb-ft of torque at 4000 rpm.

4缸机为16气门DOHC（双凸轮抽）设计，配备丰田VVT-i（智能正时可变气门控制系统），最大功率179hp/6000rpm(131kw/6000rpm),最大扭矩172lb-ft/4000rpm(233Nm/4000rpm).

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The effective anti-wear additive system minimizes wear in even the most sophisticated valve train mechanisms, including those with variable valve timing.

在有效的抗磨损添加剂磨损降到最低，即使在最先进的气门驱动机制，包括可变气门正时的。

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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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