[CVVT System Mode]

Fig 1: CVVT System Mode Graph (1 Of 2)

Courtesy of KIA MOTORS AMERICA, INC.

Fig 2: CVVT System Mode Graph (2 Of 2)

Courtesy of KIA MOTORS AMERICA, INC.

Driving Condition	Exhaust Valve		Intake Valve
Driving Condition	Valve Timing	Effect	Valve Timing	Effect
Low Speed/Low Load	Completely Advance	Valve Under-lap Improvement of combustion stability	Completely Retard	Valve Under-lap Improvement of combustion stability
Part Load	Retard	Increase of expansion work Reduction of pumping loss Reduction of HC	Retard	Reduction of pumping loss
Low Speed/High Loa	Retard	Increase of expansion work	Advance	Prevention of intake back flow (Improvement of volumetric efficiency)
High Speed/High Load	Advance	Reduction of pumping loss	Retard	Improvement of volumetric efficiency