Quattro IV ...???

[Phil Payne]

> II: Torsen center diff, open rear, lockable rear via vacuum actuation
> (80/90q, 100/200q, C4 100q, UrS (except '95.5+))

Also ur-quattro, mid-87 to end of production.  "Limited slip rear differential" on these cars is a translation problem - it's a
normal locker with speed-related disengagement, just like the others.

--
  Phil Payne
  http://www.isham-research.com/quattro
  +44 7785 302 803
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