Alfa Romeo Tipo B Monoposto: F1's shape of things to come

Alfa’s Tipo B Monoposto wasn’t motor racing’s first single-seater, but it defined a design direction that endures in the Grand Prix cars of today

Grand Prix motor racing was rudderless by 1930. Attempts at codification since the shrunken grids and eventual demise, after 1927, of its 1.5-litre formula had included: a consumption formula for oil and fuel, the latter being of specified density and (later) blend; a sliding scale of minimum weights; mandatory cockpit widths; and a proposed supercharger ban (except on two-strokes!). All were routinely ignored. Races in the main were Formule Libre affairs and a world championship (for manufacturers), founded in 1925, was rendered redundant after three seasons.

L’Association Internationale des Automobile Clubs Reconnus (AIACR), the governing body, capitulated and made things simpler for 1931: rounds of its new European championship (for drivers) were open to cars of any capacity. It went simpler yet for 1932: the major GPs were halved in length – to just five hours! – and competing cars no longer had to contain two seats. Single-seaters were nothing new – one had won the inaugural Indianapolis 500 of 1911 – yet despite the ban on riding mechanics in GPs following the death of Sunbeam’s Tom Barrett at San Sebastian in 1924, provision for them had been retained in Europe. Now, therefore, was the chance for GP racing to re-establish its identity using specialised designs rather than sports cars stripped of cycle-wings and headlamps. The machine that took that chance set the template for the next quarter-century and remains an icon.

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Alfa Romeo’s ‘Monoposto’ – its familiar P3 nomenclature came later – was a triumph of packaging, blessed with sufficient power in all the right places, agile handling and excellent reliability from the off. It was beautiful, too. New signing Rudolf Caracciola, more used to manhandling miracles from elephantine Mercedes-Benz, realised the moment he tested it that the sport had turned a corner. He told its designer: “Your car is as fleet-footed as a ballerina.”

Vittorio Jano, an Italian of Hungarian descent, had joined Alfa Romeo as chief designer from Fiat in 1923 and made an immediate impact with his P2 GP car, winner of that inaugural world championship. He followed it with the superb 6C sports cars – 1500 and 1750 models – that put the Milanese marque on an improved financial footing and all but created the GT category. His two-seat 8C 2300 of 1931 – its Monza appellation came later – was a natural progression and would provide Monoposto’s underpinnings. His (unnatural) first single-seater of that same year, however, also played a role, albeit to a lesser extent.

Tipo A was the bastard child of GP anarchy, a 980kg monster with two supercharged 115bhp six-cylinders side by side, handed and geared together, plus parallel pairs of three-speed gearboxes (coupled levers lay to the driver’s either hand), interconnected clutches, torque tubes and differentials. Though it killed an arguably overeager Luigi Arcangeli during practice for the Italian GP at Monza, it wasn’t entirely beyond redemption: Giuseppe Campari, himself a bit of a lump, used it to win the 1931 Coppa Acerbo at Pescara, a circuit that included a twisting mountain section linking two long straights. While realising his creation’s many shortcomings, Jano saw no need to relinquish its every aspect.

Monoposto, however, was less radical, more refined and better resolved. Its steel channel-section side rails, 5in deep and braced by five cross-members – two tubular, three fabricated – and live axles located by semi-elliptic leaf springs controlled by disc-type friction shock absorbers – single at the front, doubled at the back – broke no new ground, while its engine followed the fashion for the straight-eight configuration, and its drum brakes were operated by rods. But there were plenty of neat touches, some of them innovative. 

Its drivetrain was certainly novel. Two cardan shafts within torque tubes emerged and diverged from a differential in unit with the four-speed gearbox – they were linked by a short UJ within a spherical housing – and connected to separate bevel gears and short half-shafts to each wheel. This arrangement – an adaption of Tipo A’s – helpfully placed a large mass deeply within the sprung element, pared weight from the rear axle, improved traction through a reduction in wheel-lifting torque reaction, and made for rapid ratio changes. 

A 2.6-litre motor – a gain stemming from a 12mm increase of stroke – consisted of two alloy blocks of four (with steel dry liners) separated by a gear tower driving twin overhead camshafts operating two valves per cylinder. The latter were angled at 104 degrees in a single fixed head with central spark plugs in hemispherical combustion chambers. The crankshaft, halved and bolted – at a useful gain in torsional rigidity – ran in 10 plain main bearings. Auxiliary drives from the centre of the crank also operated the ancillaries – oil and water pumps, plus a Bosch magneto – and back-to-back Roots-type superchargers, which were thus smaller for reduced rotational inertia.

The numbers, including a surprisingly low 6.5:1 compression ratio, did not grab the eye, but when allied to a 700kg car with a modest frontal area – chassis and cockpit were just 66cm across – a torquey 215bhp at 5600rpm would prove a dominant combination.

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To make doubly sure, the team employed the world’s two best drivers, and although the relationship between these alpha males was spiky and problematical to a management reporting directly to Mussolini, Tazio Nuvolari and Caracciola swept the board after the Monoposto made a winning debut in June’s Italian GP. Hence the frustration when Alfa Romeo, feeling the Depression’s pinch and brought under the umbrella of state protection, shut its Corse race shop and put the Monoposti in storage.

Unhappy at making do with a 2.6-litre version of the 8C Monza, run by the semi-works Scuderia Ferrari of Modena, Nuvolari jumped ship to Maserati mid-season in 1933 to drive its 8CM single-seater. This high-profile defection forced Alfa’s hand and it released all six cars to Scuderia Ferrari in August, allowing Luigi Fagioli and Louis Chiron to squeeze three wins apiece from the remainder of the season. There could be denying, however, that Nuvolari’s Maser was faster, though less reliable, and that modifications were needed if the Monoposto was to remain competitive in GP racing’s new world.

AIACR had again ventured to restore order and its 500km GPs of 1934 would be run to the 750kg (minus driver, fuel, oil, water and tyres) Formula much influenced by the Alfa’s speed and spec. In this way, however, it had vastly underestimated the monetary and metallurgical might of Germany’s Auto Union and Mercedes-Benz ‘Silver Arrows’. Even the updated Monoposto was significantly more powerful and faster than the governing body envisaged.

With an extra 251cc, from a 3mm increase in bore, the longer, wider and heavier 2.9 Tipo B – of which seven were made rather than a mooted batch of 25 – was good for more than 160mph despite a mandatory wider cockpit (85cm). Its 40bhp boost (at 5400rpm) and extra torque both demanded stronger, thicker gears meaning one fewer could be fitted in the same casing, to no detrimental effect on performance.

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The season began well. Brilliant Algerian newcomer Guy Moll, subsequently killed in the Coppa Acerbo, won the Monaco GP and then defeated the new Auto Unions at Berlin’s Avusrennen, the latter while driving a car comprehensively streamlined by Breda aerodynamicist Cesare Pallavicino and featuring the first 3.2-litre version – another 3mm increase of bore. Even when both Auto Union and Mercedes-Benz sent a full complement to Montlhéry’s French GP in July, Chiron mixed it with them before leading home a Tipo B 1-2-3. Thereafter, however, the low-slung German cars, with their leaps in capacity and horsepower, plus independent suspension and hydraulic brakes, gained the upper hand, leaving the previous benchmark to mop up a slew of minor victories.

It was more of the same in 1935 despite Nuvolari’s return – rival Achille Varzi had beaten him to a seat at Auto Union – and yet more updates for six Tipo Bs. At least three now featured Dubonnet independent front suspension: low-mounted horizontal units with a coil spring in an oil bath and an integral external friction damper were operated by a leading swing arm through a bell-crank, and pivoted on stub axles at each end of a tubular cross-member attached to a chassis now shorn of its dumb-irons. This method reduced unsprung weight and shock loadings through the steering.  

Independent rear suspension – Porsche-type swing axles located by forward radius rods and controlled by an underslung transverse leaf spring – was tested and rejected. But Bugatti-type reversed quarter-elliptic leaf springs cantilevered from the frame’s extreme rear were employed in the belief that they fed preferable loads through the chassis. Hydraulic brakes – Ariston by Farina of Turin – were fitted, and the 265bhp 3.2 became the norm. A bigger motor was fitted to two cars for the French GP at Montlhéry – Jano told Motor Sport the exact size was 3450cc – and though they were quick – Nuvolari led and set fastest lap – they proved too powerful at 330bhp for their transmissions.

The wins continued to pile up and included, ironically, victory in the Mille Miglia for Carlo Pintacuda aboard a marginal two-seat conversion with cycle wings and headlamps. But it required Nuvolari’s genius, changeable conditions at the daunting Nürburgring, tailored tyres from Englebert, and bad luck for Mercedes-Benz’s Manfred von Brauchitsch, perhaps occasioned by poor judgment, for this great but fading car to guarantee its immortality…