[A4] Quattro, Torsen, Haldex and others...

[Brian White]

> >In fact, my Miata has a TORSEN in it and it makes it a handful in 
> >the rain. <grin>
> 
> 	a handful?  how so?
> 
> 	all i know is that i've not liked the feeling of halidex, and that
> i feel more secure on the limit in TORSEN.  i felt *most* secure, though,
> in my ur-quattro, with the first generation quattro system.

Because the TORSEN in my Miata is a limited slip rear differential!  haha...makes for a slight bit 
of oversteer in the rain.  Fun though.

Someone mentioned that Quattro is more of a marketting term lately.  True.  But I was meaning 
Quattro in the old school mechanical AWD system that Audi uses (except for the TT of course).

The confusion has been going on for a long time.  Traditional Quattro in Audis was also used in the 
Volkswagen Quantum Syncro, but badged as Syncro.  Syncro on the Volkswagen Westfalia and Vanagon 
was a Steyer-Daimler-Puch system completely unrelated to Quattro/Syncro.  And to throw another bone 
in the system, Syncro also refered to a viscous-coupling system used on the Passat G60 Syncro, the 
Golf Syncro, and the Golf Rallye.  Volkswagen renamed their AWD systems 4Motion in 2000 or so, thus 
arriving on our shores a Passat 4Motion with all wheel drive, but this 4Motion wasn't the viscous 
coupling because it used the Audi Quattro system.  And alas, the TT, which is a transverse layout 
on the A4 chassis (Volkswagen chassis designation) uses the Volkswagen 4Motion system with Haldex 
diff (used on the Golf R32 labeled as 4Motion) but they call it Quattro.  This was an evolution of 
the old viscous Syncro system used in the Golf/Passat G60/etc. <grin>

I hope that clears up some confusion.

My thoughts stand though on the TORSEN diff in the traditional Quattro system.   Quattro with the 
TORSEN center diff is good, but Quattros were good long before the TORSEN was used as the center 
diff.  Also, the Audi Quattro system only splits torque between axles, not wheels.  So a situation 
where only one wheel has traction and the car doesn't move at all.  That's where the advantages of 
electronically controled AWD systems come into play.  I'm not sure the Golf 4Motion system can do 
this, but the BMW iX system will.  One wheel with traction and 3 without?  The car moves forward.  
The Quattro will fail this test.

That said, I'm still a Quattro fan.  <grin>