Mad Rat clutch slip with brushless motor

[sprintir]

I read somewhere that one way to set the clutch up was to hold the back of the car and apply full throttle and the front wheels should just come of the ground. this i managed to do with a brushed motor.

I've now upgraded to a brushless set-up using a 9t 4300kv motor, but I've been unable to stop the clutch from slipping even with minimal throttle while holding the car and if applying to much throttle while moving.

I've checked the clutch to make sure it's aligned which it seems to be, the plates are in the recess.
can you tell me how much the adjuster clutch nut needs to be wound in,can you adjust it until there is no more adjustment left , can the adjuster nut be wound all the way in then backed off until the clutch starts to slip etc.

I have also upgraded the ball bearing in the diff I think the diff is adjusted ok but any advice would be great.
do you need to upgrade the clutch plates?
Thanks