I used your setup as a basis for one of my own. Your setup created a bit too much understeer for my driving style, so I tweaked it and it's better for me now. I posted my version also on GT vault. ID is 2090.
Allthough my racing technique relied solely accelleration:
Hit the brake about 100M or so before the turn and slide gently in position in the correct direction and gun it...simple and effective in most turns, then on others guide your car in the turns using the opponents vehicles. It may not be good driving techniques but i got the job done this time around.