im not sure how its spelled but, if you win the xsara rally car in one of the rally races, just add some turbo, only pit on the 4th lap, youll get put behind, but, none of them ever pit, so they eventually they have to go slower with the tire damage they acquire, while you just fly by them and their old tires. thats how i did it at least...
-Matthew
p.s. good luck!!!!