Mode: Free Play
Car: Bugatti Veyron Super Sport (Rent)
Track: Le Mans Circuit de la Sarthe - Old Mulsanne Circuit (Day)
Assists:-- Braking: ABS On
-- Traction & Stability: Off
-- Damage, Fuel & Wear: Cosmetic
-- Rewind: Off
Game Options:-- Max Drivatars: 0
-- Laps: 1
Mods: None
Head for the straight and you should be able to easily reach 260+ MPH. Make sure you
DO NOT REWIND, and then finish the lap to unlock the achievement.