Per the standard format for setting a land speed record, Lilja made two runs in opposite directions within the space of an hour to eliminate the effects of gradients and wind, with the two recorded speeds then averaged.
He on Saturday drove the customer-owned machine to a new record of 277.9 miles per hour on a closed 12-mile section of Highway 160 just outside of Pahrump, Nevada. For now the Agera RS holds the world production speed record.
The two-way average of 277.9mph was achieved by the Agera RS on an 11-mile stretch of road in Nevada and is 12mph faster than the existing mark held by the Bugatti Veyron Super Sport.
Last month, Bugatti set an acceleration and deceleration record, taking the Chiron hypercar from a dead stop to 248.5 miles per hour (400 km/h) then back to a stop again in a mind-bending 42. Lau also said that, since the event wasn't a tightly embargoed automaker event, some misinformation was leaking throughout the day - like a reported top speed of 291 miles per hour.
That accolade came thanks to the Swedish missile hitting 447 km/h (make that 277.9 mph), a feat that took place in Pahrump, NV.
Koenigsegg also claims to have set another record on the day. The Agera RS is powered by a 5.0 lite V8 engine which is turbo charged, it has a massive 1,380 horsepower. Guiness World Records iniitally recalled its status, but later re-instated the Veyron to the top spot after an investigation where it stated "a change to the speed limiter does not alter the fundamental design of the vehicle or its engine".
To hit these incredible speeds, the Agera RS is built using a lightweight carbon fiber body and an aluminum honeycomb monocoque structure.