The 2UR-GSE 467 horsepower V8 runs on the Atkinson cycle when operating at cruising speeds, to help enhance fuel economy. It’s a trick picked up from the brand’s hybrids. In the Atkinson cycle, the inlet valves are held open longer than normal to allow a reverse flow of intake air into the intake manifold, thereby decreasing pumping loss and increasing thermal efficiency.
The VVT-iE (Variable Valve Timing-intelligent Electric motor) technology extends the range of inlet camshaft timing adjustment for the Atkinson cycle. The instant more power is called for, the engine switches to the Otto cycle.
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