This page is dedicated to the memory of Pat Braden who died on August 25, 2002.
Seeds of Success
The years just before the second world war were equally frustrating for
Alfa Romeo and Mussolini, for both wanted to field winning grand prix
teams against the German "friends." Alfa had taken the development of
its racing cars back in-house from Scuderia Ferrari, only to make Enzo
Ferrari himself the head of the in-house group, Alfa Corse. Ferrari stayed
on with Alfa Corse for only a year. At the same time, being a
hard-headed businessman, he organized a new company, Auto Avio
Costruzioni. As part of his separation agreement with Alfa, Ferrari agreed
not to build a car under his own name for four years (thus the 815). In
exchange, he was retained as a consultant with a contract to help develop
an Alfa 1500 cc voiturette race car. Alfa even sent one of its premiere
designers, Gioacchino Colombo, to help.
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A voiturette was then the equivalent of the more modern Formula 2: a smaller-displacement, (theoretically) less-expensive car. The Italians hoped that Mercedes and Auto Union would stick to proper grand prix competition and not enter the voiturette class, which might reasonably become the exclusive domain of the Italians. To jump to the end of this little story for a moment, even that hope was vanquished: Mercedes constructed two W165 V-8 voiturette cars which took a 1-2 win at the 1939 Tripoli Grand Prix...and then never raced them again. It was an effective, albeit expensive, demonstration of the fact that the Italians had no place to hide.
From about 1937 to the beginning of the war, Alfa Romeo could only content itself with minor victories in races not contested by Mercedes-Benz or Auto Union. In point of fact, the new 6C2500 passenger car was pressed into service to win races: its 1-2 success at the Tobruk-Tripoli race in 1939 was heralded on the cover of the Alfa in-house publication, Alfa Corse, and the same illustration became a frequently reproduced ad for the marque.
The real interest in Alfa's immediate pre-war efforts centers on the voiturette 1.5-liter 8-cylinder race car first constructed at Scuderia Ferrari. The car achieved some pre-war successes, such as a 1-2-3 wins at Tripoli and again at the Coppa Acerbo (Pescara) in 1940. But the string of post-war wins for the little 8-cylinder (much augmented as the 159 of 1951) was capped by two back-to-back world championships for both car and driver in 1950 (Farina) and 1951 (Fangio). Some have tried to mitigate the success of the Alfetta, as it was affectionately known, by pointing out that the immediate post-war field was not a strong one and frequently a very mixed bag. Certainly racing began quickly after the war, and a wide variety of surviving cars were pressed into service. But the sheer accomplishment of dredging 425 hp from a 1.5 liter engine suggests just how far the engine's development was taken, and how sound the basic design was to accommodate such an output. Many of us have been fortunate to see Fangio demonstrate the car at Laguna Seca, and its high-pitched scream is not to be forgotten.
Success has many fathers: Ferrari claimed credit for the Alfetta design, as did Jano and Colombo. I am persuaded that Colombo, alone, deserves the most credit for the Type 158 Alfetta engine. Much of Jano's vocabulary is seen in its cross-section, but Jano was in disgrace (indeed, working for Lancia) during the car's development period. For a very long time I was under the impression that the Alfetta was derived from Wifredo Ricart's V-16 Alfa. That, however, is exactly the opposite of the truth.
Certain things about the Alfetta engine cross-section can almost be taken for granted: twin overhead camshafts driven by a series of gears and hemispheric combustion chambers. The single supercharger was located toward the rear of the engine and driven by an exposed shaft off the front gear train. Lightweight alloy castings formed the head/block and deep crankcase, while dry sump lubrication kept things cool and well-oiled. Fully-independent suspension featured transverse leaf springs fore and aft. Later, for the type 159, a deDion rear suspension was fitted. The initial 158 weighed 620 kg dry while the 159 tipped the scales at 710 kg.
The biggest question in most enthusiasts' minds is how Alfa managed to coax so much power from such a tiny engine. The answer is simple: supercharging, and more of the same. The complexity of the 159's final supercharger setup, however, says a lot about racing engine technology -- and the fuels -- of the time.
The first 158 Alfetta produced 195 hp with a boost of 0.8 Kg/cm2, or something on the order of 11 psi. At such boosts, the Rootes type blower (two figure-8 lobes) works just fine. But at some point as the boost pressure rises, the 0.001 in. to 0.002 in. clearance between the lobes begins to leak gasses back. In other words, there is a practical limit to the amount of boost a single Rootes blower can provide, regardless of its speed. In 1947, two-stage supercharging was employed for the type 158/47 Alfetta. That is, a smaller supercharger was used to compress the intake of a larger one. By this method, the tendency of the second supercharger to leak could be overcome by the pressure of the first. Using dual-stage supercharging in 1947, a boost of approximately 35 psi was achieved and an output of 350 hp at 8500 rpm. In its final year, the Type 159 Alfetta achieved a boost of some 42 psi and put out a measured 450 hp at 9500 rpm on the test bed. Installed in the car and limited to a racing maximum of 9300 rpm, the engine provided a reliable 425 hp.
At such outputs, the engine consumed fuel alarmingly: I have always understood that the 159 enjoyed a fuel economy of about 1.5 gallons per mile. Fuel was literally pouring through the engine: after all, that fabulous energy has to come from gobs of fuel. In a very real sense, the 159 was fuel-cooled, for the pressures and temperatures within the cylinder were beyond the mere ministrations of coolant.
The fuel, of course, was not gasoline, but a witch's brew of petro-volatiles, not-so-volatiles and unspeakables. (Well, a poetic understatement: Don Black informs that it was: 84% methanol, 14% 140-octane AVGAS, 1% defummed castor oil and 1% acetone.) It appears that the cars depended as much on fuel formulation as basic design for their power. I recall that at one of the first post-war outing of one of the Mercedes Grand Prix cars the fuel formula had been lost and the engine could hardly be made to run. And, if you have never smelled the exhaust of a car which uses castor oil in the fuel to help lubricate things, then you have missed one of life's great pleasures. In retrospect, we understand that the true limiting factor for these cars was not power but tires. Skinny and hard, they made racing like driving on perpetual ice. One of the legends of the Alfetta was that, at any speed attainable on any race course, you could break the rear wheels loose by flooring it. The same was said of the W125 Mercedes-Benz with its 646 hp. Legend for Alfa, perhaps, but a good indication of the skill it took to drive one of these fabulous cars.
Two Alfas, the 8C2900B for sport cars and the Tipo 158/159 for formula cars, link pre- and post-war technologies.
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Copyright March, 1996
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