Hi
After installing the ball diff to stop my Z spinning to the left under acceleration, i found it didn't cure the problem. Loosening the diff helps, but then i get a lack of power.
Anybody else had this problem and solved it?
The Z is a Viper with an Xspeed motor and ball diff from WFC.
Any help would be appreciated!

i kinda having the same problem even with a kyosho diff on my f1. maybe try lubing the inside. or it could just be ur tires. try switching them. do a tire rotation
your rear or front tires are not level........try getting an h-plate