We just found out that Nevada closed an 11-mile stretch of highway for the weekend in order for Koenigsegg to find out just how fast an Agera RS is; before now, the car had no official top speed. Koenigsegg Tweeted around noon that the RS managed to hit 277.9 mph on the public road, smashing the Bugatti Veyron Super Sport's previous record of 268 mph.
This mind-numbing figure is the product of the Agera's 5.0L twin-turbo V8 and incredibly light body; it has all the brute force of the Bugatti minus the AWD heft and luxury-hotel interior, so it's no surprise that it was able to smash the record given enough space.
The Agera reportedly reached 291 mph on one of its first runs, and if that's true, there was probably a pretty strong tailwind. In order to arrive at a 278 mph average, it would have had to do about 30 mph less in the other direction.
All the data was recorded on-site by Racelogic, and the car was piloted by Koenigsegg's test driver Niklas Lilja.
Congratulations to everyone on Koenigsegg's engineering team, which I'm now firmly convinced is capable of witchcraft.