Drifting requires that the diff be full lock, with no load (off throttle transitions and decel) I've read the wavetrac site. I knew about wavetrac before anyone here mentioned it. A few people have tried them on drift applications with little success. To loading is different, clutch types lock quicker and stay locked.

For road racing and drag racing the wavetrac is perfect, you dont really need a locked diff through turns, just torque biasing. Torque biasing diffs fail horribly in drifting applications, where you dont need the biasing, just a 100% locked diff that transfers equal amounts of power to both rear wheels, not thie inside or outside