the whole idea of DOHC VTEC is to allow 2 different types of cams to be in the head at one time. a mild cam for normal driving, and a more agressive cam for racing situations. this allows uniform engine breathing throughout the powerband, and allows peak torque to be made over a broader span of the RPM range.

the 3 cam lobes per 2 valves simulate the mild lift and high lift cams. allowing a smooth transition between the normal ramps, and the VTEC ramp.

~boom