Multiple choice

Continuing a trilogy that chronicles key moments in the sport’s technical evolution, we look back at a race featuring the very best from France, Britain, Italy and America
Writer Paul Fearnley

Post-war emotion was still raw in France and Mercedes was neither welcome nor invited. It wouldn’t have won in any case. Hyperinflation in Germany, when added to that denial of top-rank European competition, plus a whippy chassis and a snappy power delivery – even new design recruit Ferdinand Porsche didn’t always get it right – was hardly a recipe for Grand Prix success. An underwhelming performance at the 1923 Indianapolis 500 – it was geographically easier for America to forgive and forget – hinted that not all was well at Stuttgart.

Global motor racing, however, was in rude health. Its first extended period of regulatory stability – 1924 was the third season (of four) for the 2-litre GP formula – allowed manufacturers to hone machinery already benefiting from the slipstream of warfare’s technological acceleration. Aerial combat in particular had encouraged blue-sky thinking that resulted in more powerful, reliable and efficient engines housed within stiffer, more aerodynamic constructions. And now several of those same designers – Ettore Bugatti, Gabriel Voisin and Sunbeam’s Louis Coatalen among them – were utilising improvements in metallurgy and production methods to create nimbler racing cars, many to be driven by early aviators seeking to extend their buzz.

There were multi-cylinders – mainly straight-eights based on a Bugatti aero-engine – light alloy pistons, main roller bearings in split cages, high-voltage ignition, desmodromic valves and oil coolers (rpm was on the rise); a monocoque, an engine behind the driver, underslung chassis and full-length streamlined undertrays; and independent rear suspension (by swing axles), tubular front axles, inboard rear brakes, hydraulic brakes and servo assistance (hydraulic or mechanical). New applications arrived thick and fast.

Some, of course, were faster than others. Fiat’s angular 804 of 1922 looked plain alongside the barrel-shaped Ballots and Bugattis – and positively dull when compared to Benz’s Zeppelin-esque Tropfenwagen and the aerofoil-shaped Voisin Laboratoire of 1923 – but it was streets ahead as a sensible all-round package. Narrow, low and neat – a shape formed in a wind tunnel – it was fitted with a ‘compromise’ straight six that provided an excellent blend of power and weight distribution. Though designed by a committee – soon to be cherry-picked by rivals – it was of a whole, and won the French GP at Strasbourg by almost an hour.

Fiat did it again in 1923. Having switched to a straight-eight, it met with success using the era’s keynote development: the supercharger. Developed to maintain sea level manifold pressure at high altitude, forced induction of an explosive charge, with a resultant quicker and more complete replenishment of the mix, released bhp previously locked in torturous combustion chambers. Concomitant increases of internal stresses and mechanical and frictional losses were worth paying for a claimed 25 per cent more power. There were teething troubles – unguarded ‘blowers’ choked on grit sucked from the road in the French GP at Tours – but these were quickly remedied. Fiat’s dominant performance – when fitted with a Roots paddle-type supercharger in place of its original Wittig vane-type – in the Italian GP at Monza suggested strongly that boost was best.

Alfa Romeo and Sunbeam concurred – but then they had Fiat DNA coursing through their inlets. The individualistic Bugatti was yet to be convinced, while Delage decided against, in favour of reworking its ground-breaking 60-degree V12. But Rolland-Pilain took the plunge, when probably it should have been focusing on adjusting troublesome cuff valves.

Spread over seven makes and four countries, the field of 22 that gathered at Lyon in July 1924 for the second European GP possessed a more homogenised look – science fact rather than science fiction – but much diversity lay beneath those louvred aluminium skins. For the second time in 10 years, France’s capital of gastronomy would serve up a motor sport feast.

Not only had the cars shrunk in that time – from 4500cc and an 800kg minimum to 2000cc and 650kg – but also nine miles had been lopped from the circuit. A slot-90-right after the town of Givors obviated its winding section by the River Gier, and the climbing, narrow D34 linked to the switchback straight, now halved in length, that returned cars to the iconic downhill S-bend and hairpin that completed the lap. Little, if any, of its challenge had been lost: 30 gearchanges per lap and 130mph were required. In short, its 14.4 miles suited the sport’s new responsive style.

Henry Segrave, winner of the previous year’s French GP with Sunbeam, liked it: “It was a tricky one. It abounded in corners and had one fairly long ascent of about three miles with a gradient of approximately 1 in 12. This was also a twisty bit, rendered all the more formidable by the fact that if one did happen to go off the road, one would fall at least a couple of hundred feet.”

Sunbeam had benefited from the faster Fiats’ failures at Tours. Here, however, the British marque possessed the quickest car. Canny Coatalen had for 1923 prised designers Vincenzo Bertarione and Walter Becchia from Fiat. But it was work done by his Experimental Department in Wolverhampton, overseen by Captain J S  Irving, which provided this new, longer and lower machine. Whereas Mercedes and Fiat – and now Alfa Romeo – sited the supercharger upstream of the carburettor and had it compress air alone, Sunbeam placed its downstream so that it sucked the entire mixture into its straight-six. As well as a (guaranteed) 25 per cent power hike – 138bhp from 6psi boost at 5500rpm – this method generated a cooler charge, beneficial for the health of manifold and pistons, and an improved mix and distribution for better acceleration, as well as a smoother power curve. No wonder Sunbeam’s bonnets remained firmly shut during the official early morning practice sessions.

Engineering advantage wasn’t the only reason for its coyness. On his final test run two days before the race, Segrave noticed his oil pressure gauge flickering: “You cannot stop your engine too quickly when this happens,” he wrote in his autobiography, The Lure of Speed. “We dismantled the pressure valve and to our amazement found its seating covered with aluminium shavings. We cleaned and reassembled it and went on for a short distance, only to have the same thing occur. The car was towed back to the garage, where the entire engine was dismantled. Eventually we found that a handful of aluminium rivets had somehow got into the base chamber of the engine. It was peculiar to say the least.” The stakes were clearly high.

Alfa Romeo looked likely to be Sunbeam’s closest rival. The Milanese marque had also head-hunted Fiat personnel – Vittorio Jano and Luigi Bazzi – and the former’s P2 was the purposeful result. Running on more compliant, low-pressure Pirelli ‘balloons’ rather than beaded-edge tyres, the car caused a sensation by winning at Cremona, Italy, on its debut in June, recording 100mph-plus laps in the process.

Segrave, however, was particularly wary of Fiat’s ‘Red Devil’, Pietro Bordino, whom he considered to be the world’s best road racer. His plan, therefore, was to make the most of an allocated pole position by setting a hot pace the moment that the pilot motorcyclists peeled away to release the two-by-two rolling grid.

That’s precisely what happened – at 9am on Sunday August 3 – albeit only after an incensed Segrave had “let drive” at the overzealous gendarme who elbowed him over the pit counter and into the trench beyond. The American-born Englishman quickly rediscovered his equilibrium, despite being faced by six agitated gendarmes and their sword-wielding officer – “it was a matter of completest indifference to me what they did” – and he epitomised statuesque calm once behind the wheel. He even maintained that demeanour as he and his Italian riding mechanic Marocchi had to insert a new set of spark plugs at the end of lap three.

Bordino swept by. Despite a sore right shoulder, legacy of a practice roll that caused his car to be returned to Turin for repair, the Italian had charged from 12th on the grid. Fifth at the end of the first lap, already he had been creeping up on a Sunbeam restricted to 5200rpm because of an engine failure during practice. In the leading Fiat’s wake now were the Alfas of Antonio Ascari, Giuseppe Campari and Louis Wagner, Segrave’s team-mate Kenelm Lee Guinness and, best of the French, Alberto Divo’s Delage.

The new single-cam Bugatti Type 35s had proved fast in practice, their excellent low-down torque compensating for a lack of supercharging. With their chassis braced by four-point engine mounts and featuring side rails that thickened amidships, they handled well on mechanically braked, cast-alloy, eight-spoke wheels that saved 30lb of unsprung weight. Unfortunately, the tone of their race was set when Pierre de
Vizcaya’s completed the first lap on a ragged rim. Problems with their Dunlops blighted all five Bugs thereafter and Jean Chassagne’s 36-second swap was the result of much unwanted practice.

Bordino led until a brief, unscheduled stop after nine laps. He pitted again on lap 12. A temperamental front brake had given up the ghost completely and a half-hour of ineffectual adjustments ensued. Weakened by the absence of Carlo Salamano, injured at the Targa Florio, the Fiat team was already a busted flush.

This was a changing of the guard.

Ascari moved to the front. An ambitious son of a corn merchant from Mantua, he was an athletic, courageous improviser at the wheel. Enzo Ferrari, who was scheduled to drive the fourth P2 after a string of victories in lesser Alfas, was in awe of him. Ferrari practised briefly before packing to catch the train home surreptitiously. He cited fatigue. More likely, he had paled against his hero. At least now he could concentrate on a greater strength.

Ascari led until his planned stop on lap 16 (of 35). Jano, who had been responsible for car and race preparation at Fiat, instilled military discipline at Alfa. But the impetuous Ascari also knew his own weaknesses and was thus the only driver to carry a spare tyre as insurance.

Among those preferring to limp to the pits if necessary was Lee Guinness, whose brief lead in the only smooth-running Sunbeam was halted by a blowout of his nearside-rear Rapson. Segrave, who had pitted again on lap four, and later paused by the roadside – he was by now carrying spare plugs in his pocket – was considering unlapping himself when it happened. Both men pitted: KLG for a new tyre, Segrave for a new mechanic. Poor Marocchi had been knocked senseless by a rubber ‘bullet’.

Campari kept team-mate Ascari honest, but the latter’s advantage had grown to more than three minutes after 25 laps. It began to dwindle thereafter, and by lap 30 was down to 41 seconds. Was the leader in control or did he have a problem?

The answer came on the antepenultimate lap, when Campari emerged in the lead – and Ascari drew into the pits, fingers of flame stabbing through his bonnet: a cylinder block had cracked. Campari, his offside-front tyre bald, would win the 100,000F first prize.

Parisian Divo thrilled the crowd by closing rapidly on the hampered Alfas, but ultimately fell a minute shy. Delage’s 2LCVs, purposely overgeared for the race, impressed with their reliability – Robert Benoist finished third – but perhaps could have started their push earlier.

Having slipped as low as 14th, Segrave finished fifth, a fine recovery that benefited from the retirement of Lee Guinness. Segrave’s fastest lap – 76.26mph on lap 29 – was set when the circuit was badly cut up.

His unplanned halts cost an estimated 27 minutes and he finished 23 behind the winner after 503 miles. His problems were eventually traced to fractured wiring connecting the primary and secondary circuits of a Bosch magneto, fitted on the eve of the race.

Fiat was sore in defeat. Piqued by the defections of expensively trained technicians, the company that “did not copy; it taught, after having created” promptly withdrew from racing. It would make a victorious one-off return at the end of 1927 – but that was that. It wasn’t alone.

Sunbeam announced that it would not be fashioning cars for the new 1.5-litre formula of 1926; its sister French company Talbot-Darracq would. The cost of a fleet of increasingly complex GP cars was prohibitive for a company never paid for its war work, and it would instead concentrate on Le Mans and LSR cars – and enter receivership in 1935.

Lyon proved to be the GP high-water mark for manufacturers in the 1920s. Its success encouraged governing body AIACR to create a world championship – it ran for three years from 1925 – but fields dwindled, partly due to natural selection and partly because of the worsening global economy. Inaugural world champion Alfa Romeo would not build a 1.5-litre challenger, either. Delage did, virtually bankrupted itself doing so – and also went into receivership in 1935.

Lyon, however, had subtly pointed to the near future of GP racing.

The original privateer
Zborowski blazed a trail that would support top-line racing for decades

English Count Louis Zborowski was a fantastically rich young racer not beholden to manufacturer support. His American Miller, designed for oval circuits and steeply banked board tracks, was far from ideally matched to the demands of Lyon, but Zborowski had a good stab at it before suffering braking and steering problems. Eventually the front axle broke free of a spring after 16 laps – and thus the pioneer privateer GP entry retired.

Sadly, Zborowski was killed two months later in a works Mercedes at the Italian GP. But there had been another man present at Lyon who would continue his theme. Segrave had noticed it: “They had been turned out exactly as though they were ordinary production models.”

He was referring to the Bugattis.

After its troubled beginning, the Type 35 and its later variants would become the most successful GP-type cars of all time. Ettore’s perfectionism and increased use of American tooling at his Molsheim factory, in disputed Alsace, created a car bristling with fresh thinking and a new standard of workmanship. Its accuracy of build and interchangeable parts were symptomatic of clever platform engineering. This car was catalogued and for sale to anybody who could afford it.

Everything about it was designed to entice: its simple but beautiful shape, which contrasted sharply with the off-putting, outlandish bodies of its recent predecessors; its rasping exhaust note; and its relative ease of use and cheapness to run compared with tailor-made Fiats and Delages. Though clearly special, it was not too specialised. It boasted many brilliant parts and several quirks – form fouled function in places – but was incalculably greater than the sum of those parts and quirks.

GPs were out of necessity run to Formule Libre ‘rules’ from 1928-34 and Bugatti’s phalanx of wealthy privateers provided the core and esprit de corps that carried the sport through this troubled period. It wasn’t only Bugattis, though. Ranged against those mainly blue machines was a swathe of Alfa Romeos, a large proportion of which were fielded by a privateer team founded in 1929 and based in Modena: Scuderia Ferrari.

Ettore and Enzo had overcome their Lyon disappointments to save the sport. Whereupon order could eventually be restored, Mercedes-Benz could no longer be denied – and emotions would soon be rubbed raw once more.