2011 Bugatti Veyron Super SportTune:
"Top Speed" by "Maka91"Speed Trap:
M68 (on the highway)
You can try to save some money by purchasing the car from the auction house.
If the speed trap is not available to you, make progress on other speed traps and zones until you unlock more.
Approach the speed trap from the south, and give yourself a lot of lead up. Take gentle turns and make subtle adjustments as you in order to maintain your speed before hitting the speed trap. With the above tune, it should be relatively easy to hit the speed trap fast enough for 3 stars and the achievement.