quattro Digest, Vol 36, Issue 28

[Huw Powell]

> I do want to know, though. Did the factory quattro sports have diff 
> locks at all?

Just shooting from the hip here, but back then the street cars typically 
had atuators at each diff (center and rear) that were manually 
controlled via cables or vacuum.  The street choices were, IIRC, locked 
center or locked both.

I suspect the QS, and the race cars in general, would have had fast, 
easy, manually lockable diffs independent of each other.

> Seems to me if running unmatched tires on a street car can wear the diff 
> (or at least that's the local legend...), running at high speed with the diff 
> locked sounds like it could do damage. 

It wouldn't be needed on dry pavement, so probably would have been 
selected "off".  under slipperier conditions, one or both would be 
locked to improve traction.

Also, remember that race teams travel with vans and trailer full of 
spares - as long as the diff (or tires) last for the race or the stage, 
they can be swapped out for the next one.

The locked diff probably wouldn't get hurt, it's the tires that get 
eaten if they can't slip a bit.  Running different tires on an unlocked 
diff can supposedly "wind up" the diff and kill it, though, according 
to, as you say, the legend of the street.  This goes for 4wd trucks 
(etc.) as well as quattros.

Anyone who actually knows what they are talking about, feel free to add 
accurate details...

-- 
Huw Powell

http://www.humanspeakers.com/audi

http://www.humanthoughts.org/