This achevement will take at least an hour to earn.
Once you unlock Tier 5 (280 stars) you will be given an option to race the (N.F.S Live World Championship).
1). You will need a realy good car. Preferably one you are use to.
i used a >Lambo >Fully Upgraded.
2). You should have three options to chose from. the last one is locked. Win the first two events.
3). The first two event's has 5 race's woth a maximum of 25 stars each. The last event has 1 race. The last race.. should take atleast 8mins to get around.
The races can be a pain but take it easy and you should have no problem. for 150g i would say its worth the time and efort.
Sorry if i made any spelling errors or left anything out?
have fun :)