CVTC is actually different from VTEC........VTEC has somthin to do with the cam profile and second set of lifters on the cams or somthin....we have the second set of runners in our intake manifold that open at a specific rpm, which is what you thinkin of, but thats not the "vtec" of nissan, CVTC is CONTINOUS valve timing control(or somthin like that lol)