Hi, The quickest way to change the UCD I've found, is to start a race then quit, or just do a two lap "test-a-car" race and you will get six new cars. You may get all "zeros" but you may get lucky and find that one car you've been looking for. You could also just buy the Peugeot 908 from the NCD 5Mil.... awesome. IMO the best LMP in the game. It's NEW and you don't have to get an engine re-build or chasis repair. Have fun.