Stirling Moss and the Jaguar C-type: Unearthing the Braking Innovation of 1952

The Jaguar C-type was the car that pioneered disc brake technology in 1952, when a young Stirling Moss was its driver. We reunited them at Silverstone

Andrew Frankel

The true value of most great technological breakthroughs can usually only be appreciated with the benefit of hindsight. Life didn’t change the moment Karl Benz first swung his Motorwagen into life and phutted up the road in 1886 any more than anyone had the foresight to see in 1903 that Orville Wright’s antics at Kill Devil Hills would in time expose the human race to undreamt freedoms and dangers.

So when, in 1952, a 22-year-old lad known to few outside the world of motor racing gunned his pale green Jaguar up the road from Thillois to Gueux for the 50th and final time to win an important but hardly Blue Riband sports car race at Reims, it went largely unreported in the media; it might have gained greater attention if more people had realised that behind each of the car’s Dunlop wire wheels could be found a Dunlop disc brake, but it was not something that those responsible for it wanted to publicise.

And we can only ponder just how much publicity it would have garnered if the world had then realised what we know now: that those plate brakes (as then they were called) would turn out to be the greatest single innovation in braking technology since the invention of, well, brakes.

Stirling Moss stans with Jaguar C-Type

Moss had great history with XCK005.

The lad, of course, was Stirling Moss, the Jaguar C-type this very car. If the pastel green colour surprises it is because while Stirling was a works Jaguar driver when he raced it and won with it, it wasn’t actually Jaguar’s car, but was merely loaned to the works team for the Reims race because all the factory cars were out of commission following the disastrous attempt to defend the 1951 Le Mans victory. This, then, is the fifth C-type ever built out of a total run of 53 (54 if you include XKC054, the D-type development mule), the first three being works cars none of which survive, and the still surviving fourth being supplied to Duncan Hamilton who crashed it so comprehensively at Oporto in 1953 it hospitalised him for a month. By contrast this C-type was supplied new to Tommy Wisdom (who drove it to sixth place in the 1952 Monaco Grand Prix wearing drum brakes) and despite a very active life on track, was never significantly damaged in period.https://www.motorsportmagazine.com/database/races/1952-monaco-grand-prix/

Its originality is perhaps why it survives to this day in completely standard form, from its pair of SU carburettors to the gearbox-driven Plessey pump used to boost those brakes.

Its 3.4-litre twin-cam engine is the same one used at Reims and with a very conservative 8:1 compression ratio would, in its day, have given a little more than 200bhp on 80-octane fuel. Today, having been excused the modern tuning techniques that have been lavished upon other cars from that period, it is entirely uncompetitive.

“That’s what I love about it, boy.” Even if you did not recognise the voice, the soubriquet at the end would reveal its owner’s identity.

The track is not the same and the weather could hardly be more different, but 56 years later, the now knighted Sir Stirling Moss is back on board XKC005, looking like he’s never been away.

However great are certain talents individually, some are never greater than when brought together, and you have only to see Britain’s first truly great racing car and racing driver of the post-war era reunited once more to know it. The C-type has been driven from its home an hour away with Stirling’s old seat under the tonneau.

Ten minutes’ spanner work later, the machine is ready once more to receive the master. He dons the obligatory Herbert Johnson helmet, hops across the sill with indecent agility for a man who – he’ll not thank me for reminding you – will be 80 next year and drops into place behind the huge alloy spoked wheel. Silverstone is sodden and for a moment I wonder even if he wants to venture out in such a car in such conditions. Then I remember whom we are dealing with.

Jaguar C-Type engine

I’d like to tell you now that Stirling has total recall of that day over half a century ago when his talent, this car and those discs changed the course of road and racing car decelerative history, but sadly I can’t. In 1952 alone Moss competed in 54 of the 529 races he entered before that Goodwood accident (not including rallies, trials or hillclimbs), so I think he can be forgiven if the exact details of that particular race have now eluded him. Normally he’d just refer to his famed diaries, but sadly those editions from that year are temporarily unavailable at the time.

There are other reasons why Stirling might struggle to recall the events of June 29, 1952: for a start it was a far from riveting race on a far from riveting slipstreaming circuit that suited the C-type’s superior aerodynamics very well. “I remember it was extremely hot and having a bit of a dice with a Gordini, which I think then broke, but not much after that.” No wonder; after Manzon’s Gordini bust a stub axle, Stirling drove unchallenged to the flag winning at an average of 98.2mph, but was so exhausted by the sweltering weather and the heat soak of the straight-six motor that he had to be helped from the car and propped up for the National Anthem by Jaguar team manager ‘Lofty’ England.

“The C feels more fast than feral, but at speed it also acquires a relentless quality”

But even if the race did not lend itself to long-term recall, Moss was one of a tiny number of people who absolutely appreciated its significance at the time. Of all the drivers contracted to Jaguar at the start of the disc brake’s development it was Moss who had the ability to see through its many manifest problems and identify its true potential. In Paul Skilleter’s masterly biography of Norman Dewis, there are lurid tales of centre pedals going to the floor at three-figure speeds during testing, for which the only approved protocol was to change down, turn into the fast approaching corner and then spin the car, all of which appeared to leave Dewis entirely unfazed.

“I’d done a lot of work with Norman and Dunlop trying to fix the disc brakes and while there were some terrible problems, we could see that if they could be ironed out the advantage they’d give us would be simply incredible. Back then if you treated conventional drum brakes as we now do discs, you’d be out of brakes in a couple of laps, maybe less. If your brakes were going to survive they had to be managed throughout the race, meaning you could never use them as you wanted. Even then we could see that discs offered the possibility of being able to brake as hard as you could for every corner on every lap for the duration of the race.”

Jaguar C-Type steering-wheel

Indeed it is Stirling who claims the credit for persuading William Lyons and Bill Heynes to enter the Reims race and to annex the Wisdom C-type for those purposes.

Why Reims? “It’s simple, really. The brakes had the potential alright but we were still boiling the fluid and having problems with knock-off [a condition where the flexing of the hub in cornering pushed the pads away from the disc resulting in a pedal that sank to the floor the next time it was touched]. We were also worried about pad life, and at Reims they only had to last 50 laps. The big long straights not only suited the C-type, they also gave the brakes time and air to cool off.”

Even so, Stirling had fast developed the habit of giving the brakes a quick precautionary stab just before they were really needed to make sure the pads were properly relocated, and while the brakes appear to have worked precisely as they should have during the race, when the car came to be driven away at the end, the few minutes standing still in the sunshine was all it took to overheat the fluid and sink the pedal to the floor once more.

There will be no such problems today. Silverstone is awash, the modern fluid has a boiling point far above that available in 1952 and in this weather and that car no-one, not even Stirling Moss, is going to be flat out, least of all with the world’s worst passenger sitting next to him. Which is me.

He sits in the way he always has, upright and straight-armed. It may not perhaps be the most orthopaedically correct driving position, but it is his trademark and with his record it’s not something I’m going to question. He turns the small key and despite the fob completely obscuring the starter button below, his finger finds it at once. He’s been here before.

“Quiet, isn’t it?” he says with considerable surprise. Those stubby side-exit exhausts look mighty loud but the standard specification of the engine means conversation is still eminently possible above the burble of the just awakened twin-cam straight six.

The gearbox is slow, awkward and not really suited to the free-revving nature of the engine, but so wide is its torque spread that here on Silverstone’s ultra-quick Historic Grand Prix circuit you’d only use the top two of its four ratios. We’re already into third as the pitlane merges into the track, the engine is singing its inimitable tune and Moss is ready to go to work.

Jaguar C-Type filler-cap

What strikes you most, apart from the sheer sense of occasion of being in a C-type driven on a race track by Sir Stirling Moss, is the unfailing smoothness and precision of his every action and its corresponding consequence. Pedals are pushed firmly but progressively and never stabbed, gearshifts executed with authority but never brutality. I notice he uses every available patch of dark grey asphalt but never strays over a slippery white line or onto a kerb. What he is doing is creating time for himself to concentrate on the only thing that matters: going forward fast. While the less skilled inputs of others elicit unpredicted reactions which then need managing, if a car driven by Moss is seen to be sliding, it is you feel only because it suits him for it to be in that condition at that time.

We continue around the lap, flowing through the Becketts complex and down onto the Hangar Straight. At Reims Stirling would undoubtedly have been caning this very engine past 6000rpm in his battle with Manzon but this motor is so flexible and the track so wet that 5000rpm is enough today; more than enough, indeed, to see the thick end of 120mph on the clock in remarkably short order. The C feels more fast than feral, but as speed accrues so it also acquires a relentless quality you don’t feel in other early post-war racers.

It is, of course, Malcolm Sayer’s peerless aerodynamics which means that while others run into a wall of air above 100mph, the C-type merely splits it asunder.

Through Club, under the bridge and into the complex, I watch Sir Stirling’s feet. He’s brushing the brakes on entry, not to slow the car but simply and ever so gently just to trim its balance, yet I can barely feel it sliding beneath us.

Then the arm shoots instinctively up into the air as it has so many thousands of times in a racing career six decades long and in a moment the Jaguar turns off the track, and is coasting down the pitlane, engine off, to return to rest.

It’s only been one lap, but it is enough. Sitting there, Moss seems in no hurry to leave the car, despite the rain pattering down on his helmet. For a moment he seems lost in thought. “D’you know, boy,” he says eventually, “I hadn’t expected that.” To my shame I have to ask him to explain.

“I’ve driven some C-types over the years but none like this. It’s like a road car, so easy, so flexible – not very quick of course, but just lovely. I hadn’t realised she’d be such a – what’s the word? – such a lady.”

But it takes a certain calibre of man to deserve such a lady, and surely none was ever more qualified than Stirling Moss. Together they did great things and though both are now advanced in years, it was truly moving to see them together again, so fit and well and both not only capable of celebrating an event that helped change road and racing car history, but able to do so in such effortless, graceful style.

Thanks to the organisers of the Silverstone Classic and to Duncan Wiltshire of Motor Racing Legends for all their help with making this feature.

Jaguar C-Type Wheel


XKC005 competition history

May 26, 1952  – Supplied to Tommy Wisdom and Bill Cannell

June 2, 1952 – Monaco Grand Prix, driven by Wisdom. Result: 6th. The first non-Ferrari home, also the first race by a privately-owned C-type

June 29, 1952 – Reims 50-lap Marne Grand Prix support race, driven by Moss. Result: 1st. The first competition victory for a car using disc brakes

August 2, 1952 – Boreham, driven by Moss. Result: 1st. Pole position, fastest lap

August 23, 1952 – Turnberry, driven by Moss. Result: 1st

September 27, 1952 – Goodwood, driven by Moss. Result: 2nd. Pole position, lap record

October 11, 1952 – Charterhall, driven by Moss. Result: 2nd

April 26, 1953 – Mille Miglia, driven by Tony Rolt, co-driven by Len Hayden.
Result: retired. Car was loaned to Jaguar and entered as a works car, retired through engine failure

September 1953 – Sold to Brigadier Michael Head with original drum brakes and campaigned successfully through 1954, particularly in Sweden

Taken from Motor Sport, August 2008