Bugatti Veyron EB 16.4 Grand Sport

For top speed mode the driver must, while at rest, toggle a special top speed key to the left of the driver's seat. A checklist then establishes whether the car and its driver are ready to attempt to reach 407 km/h (253 mph). If so, the rear spoiler retracts, the front air diffusers shut, and normal 12.5 cm (4.9 in) ground clearance drops to 6.5 cm (2.6 in).

Done