Just for the archives, the Alfa Romeo that is on display at the Indy 500 museum.
...it was from the 16C-316 that the Type 158 design of Colombo was derived.
158, of course, implies 1,500cc and eight cylinders, and the engine was, in effect, half the V16 of the 316, having the same bore and stroke of 58 x 70mm with a total capacity of 1,479cc.
[...]
In 1938 the Alfettas were like the 308 cars in appearance though, of course, smaller but many alterations were made in them after Tripoli in 1939. [...] In appearance, the cars were also changed and they now resembled the cars of the 1-1/2-litre post-war formula.
With the 8C-308 of 1938, designed for the 3-litre formula, came a change in the nomenclature, the type designation meaning eight cylinders and 3-litres. A factory sheet gives it as the 8C 308/2900.
The tubular chassis was adevelopment of that on the 12C-37, and it was a leak in the saddle tank which caused Nuvolari's 8C-308 to catch fire in practice a Pau in 1938.
The engine was developed from the famous 2.9B Monoposto unit, and at last a step was taken which had puzzled many people as to why it had not been done long before -- namely the bore was increased from 68mm to 69mm so that the capacity of the 69 x 100mm engine was 2,994cc instead of the old 2,905cc. It now developed 295bhp at 6,000rpm, and the makers gave it a maximum speed of 168mph.
The 8C-308m with the faithful old eight cylinder engine in the new chassis, was something of a stop-gap, for the makers were pinning their hopes on the twelve cylinder and, in particular, the sixteen cylinder engine, which they intended to develop in order to catch up with the Germans. Nevertheless the 8C-308 was a good car, if too slow for the formula races it took part in. In later years Galvez in Argentina and Landi in Brazil won several races with this model, as did Jean Pierre Wimille soon after the War.
The car which Sommer raced before the War, and which still holds the Monthlery lap record, appeared at Indianapolis in 1940 entered by Wharston-Dewart Inc. for Chester Miller to drive and finished seventeenth after qualifying at 121.322mph. Almost certainly it was this same 8C-308 which appeared at Indianapolis in 1946 enetered by Milt Maron for Louis Devant to drive. Devant qualified at 119.335mph and finished sixth.
In 1947 Marion entered the car with Walt Brown at the wheel, and he finished seventh after qualifying at 118.335mph.
In 1948 Johnny Mauro, who now has a motor business in Denver, Colorado, bought th ecar from marion in New York, qualified at 121.79mph at Indianapolis and finished eighth.
Of the 1951 race Mr Mauro writes: 'The car was fast becoming obsolete at the speedway, so I reworked the engine as to get 500 more rpm out of it fo rthe 1951 race and blew it up. I sold it to a fellow in Ohio and he turned up at the speedway with a 270 Offy in it. I drove it to compare, but it was not the same car. I would go on record to say that the 308 Alfa Romeo was one of the greatest Race Cars that was ever built. I enjoyed driving it very much.' Johnny Mauro also drove the 308 at Pikes Peak Hill Climb.
The racing cars dealt with here are those which came after the famous 2.9B Monopostos. Every one of the G.P. cars had independent suspension front and rear of a design that is common to all. That is trailing links with coil springs in hydraulic dampers in the front, and swing axles with a transverse leaf spring below the axle housing at the rear. Gearboxes were integral with the rear axle, and brakes were hydraulic.