Ferrari 125 F1

The 125 F1 used a supercharged 1.5-litre V12 engine and sported a steel tube-frame chassis with longitudinal and cross members.^[1] It had a double wishbone suspension with a transverse leaf spring in front and a torsion bar in the rear which was upgraded to a de Dion tube for 1950. Worm and sector steering and four-wheel drum brakes were the norm for the time. The 2,160 mm (85 in) wheelbase was uprated to 2,320 mm (91 in) in the 1949 redesign. The chassis and transmission design was by Valerio Colotti.

The 125 F1 was powered by Colombo's 1.5-litre (1497 cc/91 in³) V12. The engine's name, and the car powered by it, the 125 S sports racer, were derived from the tiny 124.73 cc (7.6 cu in) 55 mm (2.17 in) by 52.5 mm (2.07 in) cylinders. It had a single overhead camshaft on each bank of cylinders with a 60° angle between the two banks. The engine had two valves per cylinder fed through one Weber 40DOC3 or 50WCF carburettor. With just a 6.5:1 compression ratio, the supercharged engine still produced 230 PS (169 kW; 227 hp) at 7000 rpm.^[3] However, the Roots-type single-stage supercharger was incapable of producing the high-end power required to compete with the strong eight-cylinder Alfa Romeo 158 and four-cylinder Maserati 4CLT. Strong driving and a nimble chassis, however, allowed the company to place third in its first outing, at the Italian Grand Prix on 5 September 1948 and the company persevered in racing.

For 1949, the engine was further modified with dual overhead camshafts (though still two valves per cylinder) and a two-stage supercharger. This combination gave the car better top-end performance and the resulting 260–280 PS (191–206 kW; 256–276 hp) gave it five Grand Prix wins.^[4] Development continued the following year, but the problematic superchargers were dropped in favor of larger displacement and Lampredi's 275 engine superseded the original Colombo engine.

The original chassis have been lost (used for Ferrari 275 F1), but an exact replica with the original Colombo engine currently resides in Museo Ferrari in Maranello alongside newer Ferrari F1 machines.