My right leg and foot are shaking from adrenalin. It’s okay, I tell myself; the marshal at the start of the Goodwood hillclimb can’t see. Nor can the 100,000 visitors who’ve come to watch man and machine do battle with the hill. Up come the marshal’s fingers. Five, push the clutch; four, steady the revs; three, look down the road to the first right-hander just after the foot bridge; two, take a deep breath and remind myself not to bin it; one… go!

Up comes the clutch. Down goes the accelerator. The skinny tyres spin merrily and the BMW’s straight-six engine is soon putt-putt-puttering as it bounces off its retro-fitted rev limiter, added as a result of the rev counter being somewhat slower-witted than the crankshaft.

Second gear comes and goes with a bob of the nose and a dip of the achingly beautiful tail. There’s time for third gear, before a spot of braking for the next right-hand bend, opposite the Gurney Pavilion, and down to second gear. Damn! It’s too low. Again, the engine runs out of revs, midway through the bend. Note to self for the next run: use third.

Molecomb has been on my mind ever since the collecting area, let alone as the 328 Coupé Touring settles down along the sort-of-straight, skipping past Goodwood House and the Aston Martin DBR1 that appears to be exiting Gerry Judah’s sculpture like a kid’s Hot Wheels car firing out of a loop-the-loop.

We make it through without any drama. By now my nerves have subsided and thoughts have turned to how on earth the drivers that won the 1940 Mille Miglia, in the process well and truly putting BMW on the world’s motor racing map, managed to carry so much speed in such a dainty little thing.

At the holding area at the top of the hill, I gingerly ease myself out of the cramped confines of the 328 Touring Coupé and cast my mind back to the race that BMW considers its most significant victory in motor sport – a victory that well and truly put the young car manufacturer on the map. The 1940 Mille Miglia played out like a story embellished by Hollywood’s most imaginative script writers. The race had been reinstated after a year’s ban, following an accident which killed 10 people, seven of them children, when a Lancia left the road. Meanwhile, fans were hearing rumours that Enzo Ferrari was entering his very first racing car – albeit one that couldn’t bear his name – after parting ways with Alfa Romeo and ingeniously finding a way around ‘non-compete’ clauses in his former employer’s contract.

War had broken out between Germany, Britain and France, following the previous winter’s invasion of Poland. Mussolini hadn’t yet joined Germany in war but for 1940 he lifted the ban on racing on public roads in built-up areas. France had banned its drivers from taking part but nonetheless two Delages were dispatched, with Italians in the driving seats.

“Few bet against Alfa, yet it was the Munich upstarts that won”

Alfa Romeo is the odds-on favourite for the reconfigured and renamed race – the Gran Premio di Brescia – which is held over a triangular 104-mile course with Brescia, Mantua and Cremona at the corners. From Milan, four 6C 2500 Tipo 256 models are dispatched with orders to bring home the silverware. Few bet against them, given that the company counted 10 victories at the Mille Miglia to its name. Yet in the end it was the upstarts from Munich that won.

Reaching that point had been a long-held objective for BMW. The company had launched the 328 roadster in June 1936, at the Nürburgring – where else? – a matter of weeks ahead of the infamous Berlin Olympics. There it would take part in its first race, the International Eifel Race, and win its class in front of 250,000 spectators, setting the fastest overall lap in the process.

Winning on home soil was one thing, however. It would be quite another to take the spoils at international events. At least, that was the view of Harold John Aldington, founding partner of AFN, BMW’s importer in Britain. Aldington had spotted the potential of the car’s predecessor, the 319, and brokered a deal for BMW to ship cars over in right-hand-drive form as Frazer Nash-BMWs. After racing a 328 to victory in the Schleissheimer Dreiecksrennen, Aldington used his connections at BMW to persuade the powers that be to give the car a run outside Germany.

The light and agile 328 started to clean up in its class, taking wins wherever it appeared, including at the Tourist Trophy, Alpine Rally, RAC Rally, Le Mans and more.

For 1938 four 328 roadsters took part in the Mille Miglia, racing from Brescia to Rome and back, two entered by the factory and two by NSKK, Nazi Germany’s National Socialist Motor Corps. To the surprise of the millions of Italians who came out to cheer a field mostly made up of home-grown entries, the little BMWs breezed it, taking a 1-2-3-4 in the 2-litre class and securing eighth overall against far more powerful machinery.

‘Gratuliere!’ proclaimed the top brass; ‘Now we want to win the race outright.’ The engineers knew that the drag of the 328 roadster’s open body was a hurdle too far: a new coupé body was needed to make the car faster still. They knew as much because they had been experimenting with closed cockpits. Wunibald Kamm, an automotive engineer and aerodynamicist, conducted BMW’s first wind-tunnel tests with a 328. It might have been exceptionally streamlined, but to drive it was something of a disaster. The car reportedly wandered about like it had knocked back six steins of Bavaria’s strongest Bockbier.

More development was needed. But running out of time and under pressure from the NSKK, to which it was obliged to supply competitive cars for races including the 1939 Le Mans, BMW turned to Carrozzeria Touring. The Italian coachbuilder had no shortage of experience in the field of lightweight specials and was instructed to set to work on a 328 spaceframe chassis.

Within four weeks, the Touring Coupé was born. It was – and still is – beautiful. An exquisitely proportioned thing that you could quite happily spend all day admiring. It may not cut through the air as efficiently as the Kamm Coupé but it still did the job: at Le Mans it won its class and finished fifth overall. Over the 24 hours, its average speed was 84mph. This showed just how little weight the 2-litre naturally aspirated straight-six engine had to propel, with the car a modest 780kg, while the bodywork was as slippery as a fish.

For 1940 the target was clear: win the Mille Miglia

That engine had been subject to much development during its competition life. Reinforced crankshafts now featured nine counterweights to eliminate the risk of bending. The control of larger valves was improved with a new cylinder head, and the engine was capable of spinning to 6000rpm and produced 136hp, compared with around 4500rpm and 80hp for the standard motor.

For 1940, the target was clear: win the Mille Miglia. The new 103-mile course was a triangular formation linking Brescia, Cremona and Mantua. With a new circuit came a new name, the First Gran Premio Brescia delle Mille Miglia.

Three roadsters started, tasked to make sure they got to the end so BMW could claim the manufacturers’ cup. The Kamm Coupé and Touring Coupé also ran, and the hope was they could strike out for the lead.

The race started at 4am with cars leaving the line in one-minute intervals. The first BMW started off at 4.40am. By the end of the first lap, Fritz Huschke von Hanstein, in the Touring Coupé, was 90 seconds ahead of his closest pursuer. He never looked back.

So wired was von Hanstein that he had to be persuaded to hand over

In fact, so wired was von Hanstein that he had to be forcefully persuaded to hand over driving duties to his co-driver Walter Bäumer, as per the team’s agreed strategy. The 328 Touring Coupé won the race outright, 15 minutes ahead of an Alfa Romeo 6C 2500 (Tipo 256), a feat that was as much an astonishment to Alfa as it was to the millions of Italians who heard the news on the wireless and read about it the next day in La Gazzetta dello Sport. After nearly nine hours of driving on public roads, its average speed was an eye-watering 104mph.

Today, BMW views the 328 Touring Coupé as one of the most significant, if not the most significant, car in the brand’s competition history. Little wonder. It opened the company’s eyes to the potential influence of motor sport, both as a spectacle and as a way to develop world-class cars.

It isn’t only because of its past pedigree that I was apprehensive about driving it; the car I am entrusted with at Goodwood is entirely original, unlike the Kamm Coupé, which is a replica commissioned by BMW in 2010, after the original Kamm went missing during the post-war period.

Back at the top of the Goodwood hill, I slide back into the 328 Touring Coupé’s cockpit and can now feel the heat soaking upwards through the floor. Then car’s hand-crafted aluminium bodywork could, should you choose, be lifted away entirely allowing the 328 to be driven naked down the hill. Onlookers might imagine you had committed vandalism of the highest order but actually the construction was designed so that the car could be easily worked on. Carrozzeria Touring had even developed a second spaceframe that held the body to the chassis.

Within the cabin there is precious little space. Wearing a helmet – something not period-appropriate but nowadays obligatory – my head is canted over to the middle of the car. The slung hammock-like cord seats are dainty affairs, while crash protection is nowhere to be seen: that simply didn’t exist on racing cars in those days.

Delicate-looking instruments with black-on-white graphics and hand-turned needles peer back at me. The speedometer (marked to 180kph) and rev counter (marked to 5000rpm) are inverted, while the odometer shows 15,366km. In this confined space, and set against the small instruments, the black three-spoke steering wheel seems almost overbearing.

A return down the hill allows me time to experiment with the brakes, get a better feel for the engine’s torque and weave about to build my confidence in the steering, which has some initial slack to it before the nose responds.

When my second run up the hill comes around, there is no more trepidation. Sure enough, the 328 Touring Coupé leaves the line perfectly, and my mental note about the slow-witted rev counter means each gear change is timed to perfection. The second right-hand bend goes by much faster in third this time, and the tail does a little hop, skip and jump as the combined effect of body roll, full power and skinny tyres rears its head.

It isn’t scary, though. The car remains stable, with just a slight slackening of the steering required rather than any dramatic correction, and it maintains its rasping and roaring dash toward Molecomb.

Through we go, then comes the flint wall, followed by the incline toward the finish line. The car keeps its momentum surprisingly well and feels entirely faithful from the driver’s position, accurately telegraphing what’s going on down below so that the driver can judge precisely how much he can get away with before the 328 relinquishes its hold of the road.

Now I’m a little closer to understanding exactly how this car managed an average speed of 104mph for nearly nine hours on public roads, in 1940. The drivers may not be with us any longer to share their secrets of driving in a partially resurrected Mille Miglia race – but thankfully BMW’s 328 Touring Coupé is. 

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