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Chapter 6

Racing Politics

In telling the story of Alfa, it's occasionally possible to talk about race and passenger cars in the same breath. Other times, the two paths diverge so significantly that one has to follow simultaneous but distinctly separate threads. Until 1923, Alfa's story is a monofilament of sporty passenger cars which were easily adapted for racing simply by removing most of the bodywork. Remember that the early cars were little more than chassis given over to specialist carrozeria for embodiment, anyway.
The 1914 Alfa Grand Prix car was singularly unsuccessful and so doesn't unravel the singular thread of Alfa's history. But, beginning in 1923, significant developments in race car design require separate attention.
The direction of racing history has been shaped as much by the politics of its governing bodies as technology. The governing bodies have always been French, and generally committed to achieving French supremacy in racing. That they have failed to do so is a commentary on French engineering.
The very first automobile events, the Gordon Bennett Cup, were administered by the Auto Club of France (ACF), and specified only that all the components of the car be indigenous. Since France was the largest world-wide producer of cars, the formula almost guaranteed French supremacy. The ACF went on to control race-car specifications until the early 1920s, when it was replaced by another French organization, the AIACR (International Association of Auto Clubs). Formulas restricting race-car weight, engine capacity, fuel consumption, frontal area and even number of persons aboard were all tried in an effort to moderate speeds. Each regulation served to produce only more clever ways of increasing speeds.
In 1921, the ACF decreed a maximum displacement of 3 liters. Fiat constructed an entirely new car, the Type 801, with a twin-cam engine following the lines of the 1912 Peugeot. The Grand Prix Fiats became dominant and, when the formula was reduced to 2 liters in 1922, continued their domination with the 804, which produced 112 hp at 5000 rpm. For 1923, Fiat introduced the supercharged 8-cylinder 805 car. With 130 hp at 5500 rpm, two 805s made a 1-2 sweep of the European Grand Prix at Monza, the first grand prix won by a supercharged car. Supercharged cars would continue to reign supreme until 1952, when the FIA decreed an unsupercharged formula.
In Fiat's wake, other manufacturers, Alfa Romeo included, were just trying to play catch-up. In 1923, Fiat 6-cylinder work-alikes were introduced by Sunbeam as well as Alfa Romeo. It is clear that Merosi was uncomfortable designing racing cars. When he was asked to design a "modern" grand prix engine, he simply updated his work on the Henri-inspired 1914 GP. The GPR of 1923 was not even sorted out when Ugo Sivocci crashed in one and was killed. Romeo was intent on competing successfully in the grands prix and set about to find a designer who could make him a winning car. At the peak of his passenger-car efforts, Merosi was fired for want of a good race car.
One of the Fiat designers, Vittorio Jano, was lured away from his beloved Turin with an offer which doubled his Fiat salary. His appearance at Alfa was hardly noticed, but as he walked through the drafting room, he tapped a young draftsman to be his assistant: Luigi Fusi. Jano's first action, evidently, was to supercharge the GPR with a Wittig-type blower similar to the units used on the Fiats. But he quickly grew uncomfortable with Merosi's design.
In several weeks of intensive work, Fusi dutifully converted Jano's ideas into mechanical drawings of the new P2 Alfa Romeo. Had this car, like the 1914 Grand Prix A.L.F.A. or the 1923 GPR, been unsuccessful, we would not have to pause in our discussion of Alfa passenger cars. But the P2 quickly dominated racing and continued to be competitive over a period of six years, a remarkable achievement. The Type 35 Bugatti also dates from 1924, but in virtually every instance where the Alfa and Bugatti raced together, the Alfa won. As with Bugatti's practice of transporting race-car practice to passenger cars, many of the P2's design details, including the twin-cam head, were translated to Alfa passenger cars. For its victories and seminal design, the P2 deserves special study. The 1921 8-cylinder Fiats, from which Jano took his inspiration, introduced a one-piece crankshaft with full roller-bearings and a one-piece twin-cam cylinder head with valves set an included angle of 96 degrees. The wide valve angle allowed very-large diameter valve heads for improved breathing. The 2-liter Fiat had a bore/stroke of 60/87 mm. In Jano's design, the bore/stroke ratio was revised to 61/85 mm for a slightly lower piston speed. Both the Fiat and Alfa powerplants maxed out at 5500 rpm, the Fiat giving 130 hp and the Alfa 140 hp. The P2 engine was built up of three large castings: an iron cylinder head in unit with the cylinders, cast without water passages; a shallow alloy crankcase which split at the center-line of the main bearings and a deep, lower crankcase half in alloy with large bearing supports. The through-bolts which connected the two crankcase halves also secured the cylinder block. The sump was little more than a ribbed plate, since dry-sump forced lubrication was used. Thin sheets of metal were welded around the cylinders to provide jackets for the coolant, a Mercedes technique. The roller bearings gave superior load-bearing capabilities with minimal lubrication needs and reduced drag from friction. The mains and rod big-ends were split so they could be assembled to the crankshaft, and semicircular cages were used to maintain individual roller spacing.
While a Wittig-type positive-displacement supercharger had been tried on the GPR Alfa, Jano elected to use a Rootes-type blower for the P2. The unit was driven at 1.2 times crank speed for a boost of 10 psi. The Rootes unit, which uses two figure-8 lobes, was the preferred performance-enhancer for sporty cars in the 1930s. Looking ahead for just a moment, the two lobes run with about 0.002 in. clearance, so there is a boost pressure above which the blower begins to leak back into the carburetor. For this reason, additional supercharging pressure can only be gained by feeding one blower with another, the 2-stage technique employed by the Type 159 Alfa of 1951 to develop 425 hp from only 1.5 liters.
On the P2, the supercharger lobes were displayed horizontally and an air inlet was provided on both sides of the casting. Pressurized air was delivered from beneath the supercharger to a finned tube which led along the frame rails to a plenum on which two updraft carburetors were mounted. Two two-into-four manifolds completed the intake plumbing. The exhaust featured a graceful eight-into-one manifold which maintained its elevation along the length of the car.
The chassis of the P2 was thoroughly classic: a ladder-type layout with solid front and rear axles on semi-elliptic springs. The rear of the chassis was curved to match the tapered bodywork and the rear springs were splayed inward at the rear to match the curve of the chassis. The engine mounted to the chassis solidly at three places and a torque-tube drive was used, with a single universal joint located behind the 4-speed transmission.
According to Fusi, only six of these cars were produced. One survives today in the Alfa museum and another, in the Carlo Biscaretti museum, is Varzi's P2 which was fitted in 1930 with a 1750 Gran Sport radiator to improve cooling. Other modifications to Varzi's car included reversing the relationship between the supercharger and carburetors and fitting a 6C1750 front axle, steering and brakes.
The P2 became the first world championship Alfa in 1925, earning Alfa a garland around the badge which it displayed proudly until some unlettered nitwit deleted it in the name of modernization.

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Copyright March, 1996

Paul Negyesi
Budapest, Hungary.
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