I recall playing with ODE in the past and the one thing I just could not get it to do was power slide handling for a car. this made it hard for me to really finish the racing game i had at the time, cos turning sharp corners either meant you were on your roof or you had to slow down..
Took me ages to find the solution, which wasn't perfect. i effectively place the COG slightly below the car body. it enables you to slide :) I recently said drift too, although if i'm honest you can't hold a drift for more than a second or two, tweaking would fix that, but i dont want to tweak anymore :P