It just after 4.00am on 11 June 1964, an immaculately dressed racing driver climbed aboard an AC Cobra Coupé racing car and headed out of the Blue Boar services on the M1 motorway. His name was Jack Sears and among his claims to fame were already to have become the first British Saloon Car champion and being team-mate to Jim Clark. He’s connected to Autocar too, his friendship with then sports editor and soon-to-be-editor Peter Garnier such that Jack was already godfather to Garnier’s young son, Mark.
In the early morning light, he accelerated smoothly up through the gears. He was there to discover the car’s top speed – not for fun, but crucially to make sure the car was stable and properly geared to race at Le Mans just nine days later. There was no track in the UK where you could run fast enough to simulate the Mulsanne Straight, for even at MIRA the car would not exceed 165mph.
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The car passed that point with ease, Jack sitting back, hands light on the wheel, looking at the rev-counter needle (it had no speedometer) until at 6500rpm it moved no more. Information banked, he peeled off at the next junction and returned to base. There his team got out their slide rules, compensated for tyre growth and concluded that the car had reached 185mph. By 5.30am, Jack was on his way home for breakfast. To him it was an event without danger or drama: just one of many information-gathering exercises required before taking on an event like Le Mans in a brand-new car.
And that would have been that, had someone who’d been there at the time not talked about it in a Fleet Street wine bar – the last place on earth you’d go to keep a secret. The next thing he knew, the story was all over the papers and there were questions being asked in the House of Commons. The following Christmas, a trial 70mph motorway speed limit was introduced – a move made permanent in 1967.
Inevitably, people put two and two together and blamed Jack and his Cobra for the introduction of motorway speed limits, despite the fact that there is no evidence to support it and Jack himself always denied it. But it’s easy to see how those considering such a move might have at least taken into account what even today seems like a fairly incredible speed to reach on a motorway, not least because of all the publicity it attracted.
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The cars of the next few
Kw not BHP.....
That's where cars are changing, 0-60, 0-100mph can thanks to instant torque be reached in almost the blink of an Eye, top speeds to some extent don't really matter, in the next few months someone will top 300MPH, do we want to go faster than that?, where could you go faster than that?, why would you want to go faster than that?, EV power has given us access to almost hyper acceleration, Tesla have been bragging there up and coming roadster will do 0-60MPH in less than two seconds!, that's another pointless ambition when that happens, time travel anyone..?
186 mph on thre M1
That is what the M1 was built for in it's day but modern traffic conditions totally negate the high speed useage .I have avidly followed motorsport since the age of 15 and have even driven a Porche 911 Turbo at 160+ in the 70's across Salisbury plain where hedges etc; do not obstruct your view of on coming traffic. I was going to demonstrate the car to a London based solicitor and did so in a traffic jam in the picadilly underpass ! Having owned 17 sports cars in my younger days,including Marcos, TVR, GT6, and lastly Mazda MX5 Mk1 & 2.I find the thrill of fast driving has ceased to exsist in modern traffic conditions and multi potholed roads.I content myself with a Mitzi Colt CZ1 these days. The supercar ads should now read 0 to 60 in 3 seconds maximum speed 70mph, but bragging rights would go out of the window !