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Originally Posted by John Y
Well, I think Jim '99's info you posted was correct - because unless I'm missing somethin, it talks exclusively about Variocam - all about variable valve timing, not lift, on various models through 2006. The '07s, as I understand it form the literature, have added variocalm Plus - which allows a couple of different lift maps for the cam, as ewell as valve timing. Hey, I don't even HAVE a POrsche (yet!  ) but in essence what the new system allows is not only varying when the valves open and close and how long they stay that way, but now, Variocam Plus also varies how much they open. |
Hi,
Yes you are correct. VarioCam is just a phase shifter - shifting the phase
and duration which increases/decreases Valve Overlap, but it doesn't do a thing to the Lift. VarioCam Plus also varies Valve Lift. Also, on VarioCam, only the Intake Cam's (2) Phase is shifted.
But, remember, this is the mechanical timing only. It is the DME which synchronizes this timing with the Spark and Injector duration to take advantage of, and maximize, this mechanical variance. The DME has different programming throughout the MY and is mostly responsible for the HP gains at the center of this inquiry. Hope this helps...
Happy Motoring!... Jim'99