Torque Split and other AWD questions

[SebringSilver]

In my continuing research on the R8, I've noticed that the default torque split is different for the V-8 car compared to the V-10 car. According to some sources, the default torque split on the V-8 is 35/65, and on the V-10, it's 15/85. But my salesperson told me that the R8 (we were talking about the 4.2) only sends at maximum 30% of the torque to the front wheels. I'm a little bit confused.

And as for the type of all-wheel-drive system that's actually used in the R8, it seems it's neither a Torsen differential system, nor the Haldex system. So is it simply a viscous coupling of some sort, similar to a 911 C4's?

If you folks could shed some light on this, it'd be much appreciated.

Thanks.

[ianerrid]

If you do a search you get lots of contradictory results, I would only trust some kind of official Audi tech document. And as for the salesman... ;-)

[SebringSilver]

If you do a search you get lots of contradictory results, I would only trust some kind of official Audi tech document. And as for the salesman... ;-)

Yes, that's what I'm finding as well (that there is a lot of info that doesn't seem to be consistent). Oh well, the car felt great on the test drive, regardless of what the torque split is.

[desperado]

On the Audi USA website the specifications describe the center differential as a "viscous clutch". They don't specify the torque split.

On the Audi UK website, they say:

The viscous coupling correspondingly diverts between 10 and 35 per cent of the propulsive power to the front wheels (the viscous coupling transmits a maximum of 160 Nm at a speed difference of 100 rpm). This assures maximum traction, but also preserves the typically agile handling of a mid-engine sports car.

The asymmetric limited-slip differential on the rear axle makes a further contribution towards maintaining balanced handling of the Audi R8. The locking ratio is 25 per cent when accelerating and 45 per cent when coasting. In conjunction with ingenious axle kinematics, this avoids abrupt load reversal reactions, for instance if you switch from accelerating to braking while cornering.

[harrison]

Is that considered "Variable split" ?