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CVVT System Mode

G15694467Courtesy of KIA MOTORS AMERICA, INC.
(1) Low Speed/Low Load (2) Part Load
G15694468Courtesy of KIA MOTORS AMERICA, INC.
G15694469Courtesy of KIA MOTORS AMERICA, INC.
(3) Low Speed/High Load (4) High Speed/High Load
G15694470Courtesy of KIA MOTORS AMERICA, INC.
G15694471Courtesy of KIA MOTORS AMERICA, INC.
Driving Condition Exhaust Valve Intake Valve
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 * Reduction of HC Retard * Delays the closing time of intake valve to reduce pumping loss
* Increases expansion work
(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