try the ultima GTR for the cone challenges on manual tranny and keep it in second gear, do ebrake slides after every cone, just small ones to keep the kudos going, then on longer straights you can shift into 3rd but remember to keep it in second, for the speed traps, try the ferrari f430 challange, good car to do it with and the vette works well too, you can do those on automatic, if you need anymore help add my gamer tag WOLFUBERSOLDAT.