Bugatti’s decision to introduce the Chiron with a 261mph speed limiter left the question of what it was truly capable of. Now the company has revealed the spectacular answer, with a slightly modified car smashing both the production car speed record and the 300mph barrier.
British sportscar veteran, Le Mans winner and official Bugatti tester, Andy Wallace drove to an astounding 304.773mph at the VW Group’s secretive Ehra-Lessien test track in Germany.
The Chiron’s “near production” spec included an additional safety cell, aerodynamic changes and a taller seventh gear, as well as a 1578bhp version of Bugatti’s quad-turbocharged 8-litre W16 engine taken from up from the 1479bhp of the ‘standard’ car. Autocar believes that the mechanical changes will be incorporated into a celebratory limited-edition model.
Exceeding 300mph also relied on specially constructed Michelin Pilot Cup 2 tyres designed to handle the enormous forces of such speeds; at the record velocity each was turning 4100 times a minute. Each tyre was X-rayed before it was selected for use to ensure that none of the radial bands was touching each other; while this doesn’t matter at even the Chiron’s normal governed speed, it could have created heat.
Wallace also admitted that the enormous gyroscopic effect of wheels rotating so quickly became a challenge at ultra-high speeds. “At 200mph you can barely feel it, but at 300mph it’s absolutely enormous,” he told Autocar after the run, “it’s felt mostly on the front wheels and therefore the steering, like a spinning top when it starts to move it wants to continue to move.”
Dallara had designed the aerodynamic kit for the record-run – the Italian motorsport specialist builds the Chiron’s body – but there was no way to test simulation projections before the car was on track as speeds were too high for a wind tunnel. The aim was for neutral downforce, but that still meant huge forces running through the car’s structure. “Net zero downforce front and rear sounds easy, as you’ve got the static weight of the car pushing down and that’s more than heavy enough.