A CVT, or “continuously variable transmission”, is odd in that it doesn’t actually have cogs like a normal, traditional gearbox.
Instead, inside a CVT gearbox you’ll find two cones, one attached to the engine and the other to the wheels, and linked by a belt which runs between them.
As you accelerate, the cones move toward and away from each other, adjusting the position of the belt and, in turn, the gearing.
The result is a very efficient gearbox, because the gearing can be adjusted almost infinitely. This means the engine can be kept at the optimum speed at all times.
What’s more, because there are no fixed gears, there are no gear changes either – and that means smooth acceleration without any jolts.
But a CVT isn’t without its downsides. If it’s matched to a weedy engine, it’ll hold the engine at high revs as you accelerate, to extract the most power – and that can mean you hear a lot of engine noise inside the car.
Also known as: belt-and-pulley, Xtronic, E-CVT, Multitronic
Choose if: you want the smoothest acceleration with good fuel economy, and don’t mind a bit of extra engine noise
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