[greatone61]

My opinion...its could be many different combo's, one...a high stall TC coupled with the Quaife is probably the "deadliest", your leaving the line at a higher RPM which equals more power. The Quaife will send the power to the tire that grips the most and boom thats where it breaks.
Another I think could be stress on the halfshafts over time, especially with NOS, unlike other F/I applications with NOS as soon as it is in the engine your getting a sudden jump in hp and torque which is going to kind of shock the halfshafts.