'90 or '90 changed to the torsen center from the previous locking center.
quattro usually have 3:70 ratio where non q use 4:11

To check further with those better informed than me you should visit:

Audiworld.com forums.

Tonyj
'91 100q 5spd

BRIAN wrote:

> Greetings all, I'm hoping some Guru out there can tell me if the Audi
> 100/200/5000 Diff parts are interchangeable.
> I have an 016 manual transaxle but the Crown gear is stripped and I have
> been quoted over $1800 for a replacement.
> I do have access to a cheap Auto also from an Audi 100.
> My questionis .. as long as the ratio's are similar can I interchange them.
>
> Thanks in anticipation
>
>