CVVT System Mode

Fig 1: CVVT System Mode Graph Engine Speed & Load Correlation (1 Of 2)

Courtesy of HYUNDAI MOTOR AMERICA

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

Courtesy of HYUNDAI MOTOR AMERICA

INTAKE AND EXHAUST VALVE DRIVING CONDITIONS

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