At Donington in 2002 I sat in the back of a Minardi-Cosworth F1x2 two-seater being driven by Matteo Bobbi (who became FIA GT World Champion the following year). At the fastest parts of the circuit – under the bridge into the Goddards chicane, and along the start/finish straight towards Redgate – we were pulling over 15,000rpm and probably doing 170-180mph.

Minardi F1x2 two-seater at Donington

I've driven road cars at more than 140mph, but I tend not to look at the speedometer much while I'm doing it...