What is a v v t selinode - Cars & Trucks

(As in the Honda VTEC engines.) VTEC = (Variable Valve Timing and Lift Electronic Control)
In a VVT equiped engine the valve timing (How long an intake or exhaust valve is open or closed) is controled by this solenoid. As in the Honda VTEC engines there is an extra intake cam with its own rocker, which follows this cam. The profile on this cam keeps the intake valve open longer than the other cam profile. At low engine speeds, this rocker is not connected to any valves. At high engine speeds, a piston locks the extra rocker to the two rockers that control the two intake valves.