263.4kmh, or 163.7mph in old money. The maximum speed of a new twin-turbo V12 people-carrier? The speed of a motorcyclist when caught on a British motorway by police camera (true!)?
Neither; the figures date back to 1973 and refer to the fastest timed lap ever recorded at the ‘long’ Spa circuit. It was set up by Jacky Ickx during qualifying for that year’s 1000Kms race when he was at the wheel of a Ferrari 312PB prototype.
The figure is so staggering – and yet relatively unknown – that it still defies imagination. Think about it, this was the average speed over a long, long 3 minute 12.7 second lap on a closed public road course. This wasn’t some safety-fenced oval, but an honest-to-goodness ribbon of two-way blacktop snaking through trees and houses in the Ardennes region of southern Belgium.