Re: VANOS...

[MICHAEL_KOHLBRENNER@xxxxxxxxxxxxxxxxxxxxxxxx]

I said:

> The implementation in BMW's case (many other car companies use
> the same principle with varying implementations...) is through
> the use of something akin to moveable timing chain tensioners.
> For example, in the single VANOS case, the intake cam is driven
> by a chain off the exhaust cam.  There is a movable device, similar
> to a chain tensioner, that varies the length that the chain has
> to travel between the two cams, thereby changing the timing of the
> intake cam relative to the exhaust.  Porsche's implementation is
> similar as is Audi's, if I recall correctly.  Other companies use
> a device that resides within the cam drive gear "assembly" which
> continuously varies the camshaft timing relative to the drive gear.
> Toyota's VVTi does this.  I think it was Alfa, also, that used a
> similar method in one of the very earliest implementations
> somewhere around 15-25 years ago.

I have to apologize now for apparently spewing misinformation...

Someone else posted a web site with a "Land Shark" explanation
that I will have to assume is more reliable than the "previous"
explanation someone once gave me and the one upon which I based
my above post.

According to the web site, BMW uses the "variable cam sprocket
assembly" approach, rather than the "variable timing chain"
approach as I had thought.

Sorry...

Regards,
Mike Kohlbrenner

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