In a word, scary – even in a car as stable and as well developed as a Bugatti Veyron Supersport. And that’s straight from the bloke who maxed the car at VW’s Ehra-Lessien test track in Germany just a few weeks ago.

Talking to Pierre-Henri Raphanel, who drove the car to its world record breaking top speed of 268mph, I asked if he was at all nervous before doing the official timed run.

Watch the Veyron Super Sport on video, plus read the first drive review and see test pics

He said he didn’t sleep for two days before the big day. Why? Because during the various test runs he’d done leading up to main event, the car had felt fine up to 420kph (260mph) but then, for some weird reason that no one at Bugatti could fathom, it started to develop a mind of its own beyond 260mph. It started to wander left, basically, and there wasn’t a lot Raphanel could do about it other than hang on and hope.

“The car was absolutely perfect up to 420kph” he says. “But after that it did start to become quite difficult. And when we ran the car in the opposite direction – because to achieve the world record you have to run in two directions – the characteristics of the track surface was different. Again that made the car behave in a new way, and not a very nice way, beyond 420kph.”

He then explained that because this was the first time anyone had ever run in the other direction at Ehra-Lessien, there was a graining effect within the tarmac itself when running against the normal direction. And that’s what made the thing most unstable. It was new ground, basically, and the Veyron – above 260mph – just didn’t feel very nice going against the grain.

“But at that speed you cannot make any kind of correction” says Raphanel. “Because if you do it is already too late. So, yes, you could say I was a little nervous!” And that’s when Bugatti made the poor bloke sign a disclaimer, admonishing them of all responsibility in the event of the unthinkable…

Fortunately it never happened, and the car went on to set a new world record. But it was far from a walk in the park. “I didn’t sleep for another two days afterwards” says Raphanel. “And if they’d asked me to have another go, to try to go even faster, I would have said no. By then I knew I’d had enough!”