Torsen rear diff for 37/9(4.11) drivetrain with 108 flanges.

The original rear diff, is a open diff. You got the lock, but its not very good. So you can upgrade it to torsen(Torque Sensing) self-locking diff for allmost nothing. I bought mine for 150 €. If you like to go sideways, or get maximum speed round corners, then this is a must upgrade for you.

What you need:
-Your original rear diff. (Read the whole thread)
-Rear diff from Audi V8 (the model) 4.2/3.6, manual/automatic have the same diff.
-New oil seals for the V8 diff.

The converting is very straight forward. Just open both rear diffs, pull out the diff housing. Install the crown wheel from the original diff house to the torsen. Install new oil seals into the original rear axle housing, then insert the torsen diff. The lock function can stay there to seal the diff. Use the flanges from V8 diff.

I don't know if you can use the torsen diff on a original compi diff, because the compi have 100mm flanges. There are some differences on the torsen diff flanges and those from compi. I think the length may be an issue. Hopefully I will find out next week if I got time.

Good luck

the compi flanges are smaller, so you cant bolt on the compi driveshafts...