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Old 04-Sep-2009, 01:06
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John W John W is offline
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I don't think this is really helping in terms of buyer information, but since you asked here goes.

I can only think your referring to a 996, as the 993 definitely does not have variable cam timing.
I was so certain that I have gone and checked the owners manual for my car, and the various porsche books I have.
The real killer though is that I happen to have a full set of original porsche service manuals, and can categorically confirm there is one cam per cylinder head, one drive sprocket per cam, and each cam is driven by its own dual chain from the intermediate shaft, which is directly driven by the crank.
no variable valve timing anywhere in any of that.
if you want to check, this is Volume 1 - general engine, section 15. There is a nice diagram on page 15-15.

Now in the same volume of the manual, in section 24, page 24-11, there is an exploded diagram of the varioram sytem and it is entitled '911 carrera [RS] engine with varioram induction system'.

I also have a copy of PorschePET, the electronic parts catalog. nowhere does it have a link to 'variocam' for the 993 when searched.

FYI Variocam adjusts the timing between the intake and exhaust cams, as first used in the 968, and then used in the 996 (a different type of system though, called variocam-plus). Given that the 993 only has 1 cam per cylinder bank it is imposible for it to have variocam

try doing a google for 993 variocam and it saysdid you mean varioram...

Do I win a prize for being technical geek/pedant/tosser (delete as appropriate) of the week
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