Development of Innovative Variable Valve Event and Lift (VVEL) System

Nissan Motor Company has developed a compact and simple new variable valve actuation system called VVEL (Variable Valve Event and Lift) that can vary intake valve lift and valve event angle in a wide range, and adopted it on a newly developed 3.7L, V6 engine. This system combined with a variable valve timing (VTC) mechanism (or a cam phaser) has substantially enhanced engine performance attributes, namely, fuel economy, exhaust emissions, and engine output, because the system has the ability to freely control all of intake valve lift, event duration angle and phasing between intake and exhaust valves. This paper describes an outline of the VVEL system, the principle of system operation, and effects on engine performance attributes by this technology.