ok, let me try to remember what works in this game...
get a race default setup, make sure it is the stiffest one there. (make sure it is default, so i know you are dealing with a somewhat well thought out setup)
go into suspension, take the rear spring stiffness, and increase it a little, and do the same to the front. this is to minimize the weight flopping around during weight transfer/bumps etc. make sure they are not rock solid, this will make for an uncontrollable setup. drop the car, make sure it has some motion, and doesnt bounce.
adjust the dampening so it comes to rest just as it appears like it should (cant explain this well)
take the rebound dampening, and make it a little higher than the dampening (if you did the dampening right, it should be sensible) drop the car, make sure it looks good.
take the front sway bar, make it somewhat low; take the rear, make it a little higher.
i noticed the higher the sway bar, the more likely it is to slip; instead of the weight transfering for the tires to pick up grip, the weight forces the end to slip.
rebound dampening does the same; as the inside wheel wants to lift up, it is being restricted forcing to weight to want to push it.
lower the car so when you drop it, it nearly bottoms out, but not too low or you will run into problems....lowers the center of gravity.
now go into wherever the camber adjustment is...this should be negative 2ish for the front, and -1.5ish for the rear....i think....(cant remember right now)
go into drivetrain, differential, i forget...but make sure you have a clutch lsd, and make sure it locks something like 65-75% (sound right? cant remember again..), and make sure it has enough force to make that happen.
try that, and see where it brings you. report back with results, i will see if i can help you tweak it.
im not saying this is the right way to build a drift setup, or if my reasons are correct, but i forget why i used to do everything i did; or even how i did some things. these reasons and adjustments seem to make sense.