There's NO "VCD" in base 370Z model. You get VLSD with sports package and that's it. Sports package can be added to both base and touring model.
Base or Touring 370Z without sport package = OPEN DIFFERENTIAL!
Base or Touring 370Z
WITH sport package = VLSD (Viscous Limited Slip Differential)
P.S. just curious, what the heck is VCD? Video Compact Disc?