Ferrari Colombo engine

Ferrari's earliest cars used engines designed by Gioacchino Colombo, who had formerly designed Alfa Romeos for Enzo Ferrari. These V12 powerplants ranged from the diminutive 1.5 L (1497 cc) unit fitted to the 125S to the 3.3 L (3285 cc) unit in the 1966 275.

Enzo Ferrari had long admired the V12 engines of Packard, Auto Union, and Alfa Romeo (where he was long employed), but his first car, the 1940 Auto Avio Costruzione 815, used a Fiat straight-8. It was only natural that his first homegrown engine would be a V12, and the same basic design would last many years, with development continuing long after original designer Colombo had been replaced by Aurelio Lampredi as the company's marquee engine designer. Although Lampredi's engines were a real force for the company, it was Colombo's V12 which would be the primary motivator for the company's consumer products through the 1950s and 1960s.

125

The first homegrown Ferrari engine was the 125. First appearing May 11, 1947 under the hood of Ferrari's 125 S sports racer, the engine allowed the company to claim six victories in 14 races that year. The 125 S sported tiny 55.0 mm (2.2 in) by 52.5 mm (2.1 in) cylinders, the resulting 124.73 cc of each cylinder rounded up to give the engine, and the car, its name. Overall, the engine displaced exactly 1,496.77 cc (91 in³). 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 three Weber 30DCF carburettors. A 7.5:1 compression ratio yielded 118 hp (88 kW) at 6800 rpm.

Colombo and Ferrari had designed the engine with Formula 1 regulations in mind, and introduced it the next year in the company's first F1 car, the 125 F1. This time, it was supercharged, in accordance with F1 dictates, for a total output of 230 hp (172 kW) at 7,000 rpm. 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 Valentino Grand Prix on September 5, 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 280 hp (209 kW) gave it five Grand Prix wins. Development continued the following year, but the problematic superchargers were dropped in favor of larger displacement and Lampredi's 275 engine superseded the original Ferrari engine.

Applications:
* 1947 Ferrari 125 S — 118 hp (88 kW)
* 1948 Ferrari 125 F1 — Single supercharger, 230 hp (172 kW)
* 1949–1950 Ferrari 125 F1 — Dual-stage supercharger, 280 hp (209 kW)

58.8 mm stroke

The early 166, 195, and 212 cars used Colombo V12s of varying sizes. All shared the same 58.8 mm stroke, with 60, 65, and 68 mm bores giving displacements of 1995, 2341, and 2563 cc in the 166, 195, and 212 respectively. Output ranged from 105 hp to 165 hp.

250

One of the most common Colombo engines is the 250. It bowed in 1952 in the 250S and lasted through the 1963 330 America. It used a 73 mm bore with the common Colombo stroke of 58.8 mm for a total of 2953 cc.

275

The final 58.8 mm Colombo Ferrari was the 275. It used a 3286 cc variant of the V12 with a wide 77 mm bore for up to 300 hp.

330

The 1960 400 Superamerica replaced the previous model's Lampredi engine with a 3967 cc Colombo. It diverged from the standard 58.8 mm stroke with a 71 mm stroke and 77 mm bore. Output was 340 to 400 hp with triple Weber carburetors.

Although the 1963 330 series also used a 3967 cc engine with the same bore and stroke as the 400 Superamerica, this engine was quite different. It used a wider bore spacing, paving the way for future displacement increases. The spark plugs were moved and a new water pump was used. The dynamo on the prior versions was replaced by a true alternator. In the end, 300 hp (223 kW) was on tap.

Four-cam

The Colombo V12 was substantially reworked for 1967's 275 GTB/4. It still used two valves per cylinder, but dual overhead cams were now used as well. In a departure from previous Ferrari designs, the valve angle was reduced three degrees to 54° for a more-compact head. The dual camshafts also allowed the valves to be aligned "correctly" (perpendicular to the camshaft) instead of offset as in SOHC Ferraris. It was a dry-sump design with a huge 17 qt (16 L) capacity. The engine retained the bore and stroke dimensions of the 275 model for 3286 cc of displacement. Output was 330 hp (246 kW) at 8000 rpm and 240 ft.lbf (325 Nm) at 6000 rpm with six Weber 40 DCN 9 carburetors.

365

The 71 mm Colombo engine was enlarged with an 81 mm bore to 4390 cc for 1966's 365 models. This same engine would continue for the Daytona and was flattened for use in the 365 GT4 BB of 1971.

400

The Colombo engine was enlarged again to 4823 cc for 1976's 400 with the same 81 mm bore and a 78 mm stroke.

Applications:
* 1983–1985 400i

512

Another flat version (bored to 82 mm) was fitted to the 512BB. Total displacement was 4943 cc. These engines continued into the 1980s in the 412 (as the "Tipo F101") and Testarossa (as the "Tipo F113B"), only being retired in 1992 with the new Dino-based 456 V12.

Applications:
* 4943 cc
** 1977–1981 512 BB
* Fuel-injected
** 1981–1985 512 BBi
* "Tipo F113B"
** 1985–1991 Testarossa
* "Tipo F101"
** 1986–1988 412i
* "Tipo F113G"
** 1992–1995 512 TR