Leave all the settings on the car alone, drop all downforce to minimum, 0 TCS, 0 ABS. Draft your way to the front (I did it on the backstretch of lap 1). Stay on the bottom of the track and watch your mirrors. The AI slows down for turn 1 and turn 3, everytime, so even if they are ahead of you on the high side, they will drop back. But you have to stay low to keep from getting pit-manuevered. If necessary, you can float up to block on the straights, but you MUST stay low in the corners or you WILL get wrecked.