Re: quattro-digest V4 #1936

["Christopher Hanlon" <cwhanlon@eai.com>]

Gerard,

Don't know of any KKK sites, nor do I know which KKK turbo the audi uses.  I
doubt it is very different than the ones Porsche uses (k-26, k-27, etc...).

>
Could anyone explain to me what a ball bearing turbo is? I'm looking
at some funny ad for a Z3, it says:
>

Ball bearing turbo is a turbo that uses precisely what it says; ball bearings.
 So there is no need for a secondary oil line from the engine to lubricate/cool
the turbo.  The KKK series of turbos have oil ports and water ports (for water
cooling).

>
turbo companies, Aerodyne being one of the suppliers and also Garrett.
Do KKK over a turbo along these lines? How does this turbo vary from
the "standard" types? How do they get no back pressure? Is the exhaust
vanes or the impellers changed during spin-up?
>

I don't know anything about variable vane systems.  But from the sound of it,
it seems that the vanes are aligned with the flow of exhaust, eliminating back
pressure at light loads (when you don't need the turbo spinning).  If you need
the turbo, then the vanes start to face the oncoming exhaust causing the turbo
to spool up.

I know of no KKK turbo charger that acts as such.  (not that there isn't)  It
has always seemed to me that the KKK turbocharger has remained the same for
about 20 years. (can someone prove me wrong, please?)

Hope this helps.

chris

--