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What is the difference between VVT and CVT transmissions?

1Answers
MacElliana
07/28/2025

VVT and CVT transmissions have the following specific differences: In terms of nature: VVT refers to a technology in the engine, while CVT refers to the type of transmission. The technology used in VVT engines, namely continuous variable valve timing technology, can continuously adjust the opening and closing time of the engine's valves and the intake air volume, thereby improving engine power, optimizing the torque curve, and reducing fuel consumption. In terms of working principle: The working principle of VVT is that the crankshaft drives the camshaft through a timing belt, gear, or chain. The profile and position of the cam on the camshaft are usually optimized for a specific engine speed, which generally reduces the torque at low speeds and the power at high speeds. VVT technology allows it to change according to the engine's operating conditions, improving the engine's efficiency and power. The principle of CVT is that in the CVT transmission system, traditional gears are replaced by a pair of pulleys and a steel belt. Each pulley is actually a V-shaped structure composed of two conical discs. The engine shaft is connected to the small pulley, which drives the large pulley through the steel belt. When the conical discs move inward and tighten, the steel belt moves outward from the center under the pressure of the discs. Conversely, it moves inward toward the center, increasing the diameter of the disc driven by the steel belt, thus changing the transmission ratio.

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