VVT-i

VVT-i, or Variable Valve Timing with Intelligence, is an automobile variable valve timing technology developed by Toyota. The latest version of VVT-i varies the timing of the intake valves by adjusting the timing chain connecting the intake and exhaust camshafts. A pump applies hydraulic pressure to adjust the gear driving the timing chain.

Toyota recently started offering a new technology, VVTL-i, which can alter valve lift (and duration) as well as valve timing. This is accomplished similarly to Honda's VTEC by switching between two different sets of cam lobes. This system is used in the Celica GT-s engine.

For 2006, the company will add dual VVT-i, which varies timing independently on both the intake and exhaust cams. This will debut on the 2006 Toyota Avalon's 2GR-FE V6.