Originally Posted by senseiturtle
The only AWD system I'd even consider for racing is that of a Skyline's, which I believe has a continuously-variable power transfer rate, based on rate of accleration and other various conditions.
I remember it being described as this, by some magazine.. of course, I'm likely wrong, so if a skyline-guru could clarify, that'd be great,
Full throttle-
Back tires light up instantly. Computer (?) realizes that there is zero grip, and transfers just enough (up to 40%) to the front wheels to get it moving. This starts the car moving, and at the same time, allows the back tires to grip. Power is then re-routed almost fully to the back tires, but just enough remain with the front to keep from spinning the back.
---------------------------
Other than that, I'd consider AWD for autoX, but for dragging... RWD all the way.
There are several AWD systems have this variable center diff. The STi also has this computer controlled mode where power is transferred to and from wheels as wheel slip is detected. Also, the center diff can be adjusted manually in the cabin, anywhere from fully locked to 90% slip. I've heard that a lot of STi driver's lock the center diff to get the car going and switch it to automatic mode once the hit the end of first gear.