V8 torsen in Urquattro 20v

[Giacomo]

Hello, I'm trying to do this on my car, but seems not direct fit.
While tightening the bolts, still some gap remains from the V8 diff to the RR diff housing.
It seems that the bearing housing in the Urquattro side does not allow the diff to slide inside that little more I need to close everything.
I post 2 pics, anyone has done it already on this car?
Thanks




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[diesel des]

You might need an s2 rear diff housing?

[Giacomo]

I'm afraid I will.
C4 housing wouldn't fit on Urquattro subframe?

[diesel des]

C4 housing is much longer and mounts differently. Anything can me made work but I don't think it's worth the effete to make a c4 diff work in a Urq. S2 diff should be easy option.

[Giacomo]

Ok. I think I know where to get one.

[UrS4boy]

Hello, I'm trying to do this on my car, but seems not direct fit.

Sorry. I have to ask: Why do you want to go away from the lockable rear Urq diff to the Torsen V8 rear diff? What do you think that you are going to gain?

[quattro-nick]

WARNING,be carefull with your ratio!
i believe 10v urquattro has ratio 3.89 and v8 torsen 4.11
however,i dont know which ratio the gearbox has with rr 20v engine but i think it has also ratio 3.89
you can fit a v8 torsen in a typ85 or s2 diff but you still need to swap the crown wheel and pinion from urquattro for ratio 3.89 but I do not know if this can be achieved

[diesel des]

Most people say they drive better with some power oversteer on the track with the torsen. The disadvantage is that they can be more fragile if drag launched. And obviously on very slippy ground the locked diff is better.

[UrS4boy]

WARNING,be carefull with your ratio!
i believe 10v urquattro has ratio 3.89 and v8 torsen 4.11. however,i dont know which ratio the gearbox has with rr 20v engine but i think it has also ratio 3.89

Very good point. Extremely good point. Fantastic point. Remarkable point.

The 1991 UrQ WF, ALZ and ADV rear diffs are *ALL* 35/9 = 3.889, not 37/9 = 4.11 like the C4 UrSs and the V8 torsens, at least the ones with 5 and 6 spd manuals.

UrQ = http://audi.7zap.com/en/rdw/audi+qua...6/5/500-40000/

[Giacomo]

No drag launching. Just want to feel more oversteering/drift.
I know about the ratio and the need of gear swap
Also i know somebody has done this on the Urquattro RR. So it could be done.
I know there are 2 types of V8 torsen, the one in single piece and the other in 2 pieces (the one I have).
Maybe the single piece one is direct fit but if possible, I'd like to fit the one I have.

[quattro-nick]

Very good point. Extremely good point. Fantastic point. Remarkable point.

The 1991 UrQ WF, ALZ and ADV rear diffs are *ALL* 35/9 = 3.889, not 37/9 = 4.11 like the C4 UrSs and the V8 torsens, at least the ones with 5 and 6 spd manuals.

UrQ = http://audi.7zap.com/en/rdw/audi+qua...6/5/500-40000/

thanks dave

[Giacomo]

So Urq and S2 has the same gear ratio, right?
Both have manual diff lock.
If people fit torsen on S2, could be done on Urq, for the same gains.

[diesel des]

S2 have 4.11 final drive. Urq 3.89...

[goodall]

If your keeping the ur gearbox you'll need a rear diff with 3.889 ratio, the CAU code diff from a V6 coupe will provide this

[Giacomo]

The V6 diff is torsen also?
V6 coupè B4 or from a C4?

Isn't it enough to swap the gear from the Urq diff to the V8 diff?