vvtiw

VVT-iW was introduced with the 2.0L turbocharged direct-injected 8AR-FTS fitted to the Lexus NX200t. It enables the engine to operate in both the Otto and a modified-Atkinson cycle, by offering expanded valve opening angles, resulting in increased fuel-efficiency at low engine loads.[citation needed]

The electric motor in the actuator spins together with the intake camshaft as the engine runs. To maintain camshaft timing, the actuator motor will operate at the same speed as the camshaft. To advance the camshaft timing, the actuator motor will rotate slightly faster than the camshaft speed. To retard camshaft timing, the actuator motor will rotate slightly slower than camshaft speed. The speed difference between the actuator motor and camshaft timing is used to operate a mechanism that varies the camshaft timing. The benefit of the electric actuation is enhanced response and accuracy at low engine speeds and at lower temperatures. as well as a greater total range of adjustment. The combination of these factors allows more precise control, resulting in an improvement of both fuel economy, engine output and emissions performance