Originally Posted by chrisny
+1. Most of the time it operates with more of a rear bias, not front wheel, with or without sport differential, and much like BMW's x-drive.
Quattro has been around a long time and quite honestly, it sets the bar. BMW is new to the awd game by comparison.
How is this possible? Audi has a front wheel drive gearbox with a Transfer device for the rear wheels. It cannot possibly put more torque rear wards.
The BMW, Nissan GTR, Subaru are RWD gearboxes with transfer device for front wheels. So are in effect rear biased.
In extreme situations both can get to near 50:50 torque split, but are generally biased to the basic configuration. The only exception is those off road 4x4's that use a dedicated transfer case.