Alfa Romeo 12C

Alfa Romeo 12C
An Alfa Romeo 12C-36
Übersicht
Manufacturer	Alfa Romeo
Production	1936-1937
Designer	Vittorio Jano
Body and chassis
Class	Grand Prix 750 kg
Layout	FR layout
Powertrain
Engine	Roots supercharged 4.1 L 4064 cc 60° V12 370 bhp at 5800 rpm (12C-36) Roots supercharged 4.5 L 4475 cc 60° V12 430 bhp at 5800 rpm (12C-37)
Transmission	4-speed manual transmission
Dimensions
Curb weight	818 kg (1804 lb) (12C-36) 808 kg (1782 lb) (12C-37)

The Alfa Romeo 12C or Tipo C was a 12-cylinder Grand Prix car. The 12C-36 made its debut in Tripoli Grand Prix 1936, and the 12C-37 in Coppa Acerbo 1937. The 12C-36 was a Tipo C fitted with the new V12 instead of the 3.8 litre straight-eight of the 8C-35. The 12C-37 was a new car, with a lower chassis and an engine bored and stroked to 4475 cc, now with roller- instead of plain bearings and two smaller superchargers instead of a single large one. The car suffered poor handling, which could not be cured in time for the 1937 Italian GP, and thus was not successful. This is given as the reason for Vittorio Jano's resignation from Alfa Romeo at the end of 1937. The 12C-36 used the existing six Tipo C chassis. Four examples of the 12C-37 were built, although only two were actually assembled for the 1937 Coppa Acerbo and Italian GP. Early in 1938, the Tipo C (8C-35, 12C-36) chassis were modified into 308s, with the straight-eight engine fitted lower in the chassis and a completely new body. The four 12C-37 chassis were instead assembled into 312 (V12 downsized to 3-litre) and 316 (V16 obtained from two 158 engines fitted to a common crankcase) formula race cars.

Main victories

• 1936 Penya Rhin Grand Prix, Tazio Nuvolari
• 1936 Milan Grand Prix, Tazio Nuvolari
• 1936 Modena Grand Prix, Tazio Nuvolari
• 1936 Vanderbilt Cup, Tazio Nuvolari
• 1937 Milan Grand Prix, Tazio Nuvolari
• 1937 Valentino Grand Prix, Antonio Brivio
• 1937 Circuito di Napoli, Giuseppe Farina
• 1937 Genova Grand Prix, Carlo Felice Trossi

*All with 12C-36

• 
  Alfa Romeo 12C-36
• 
  Cockpit of an Alfa Romeo 12C-36

Technical Information

The table below lists the main differences and similarities between the two versions.

	Alfa Romeo 12C-36	Alfa Romeo 12C-37
engine	12 cylinder V 60º engine
displacement	4064 cc / 248 cu in	4495 cm³ / 274.3 cu in
bore × stroke	70.0mm × 88.0mm	72.0mm × 92.0mm
compression ratio	7.1 : 1	7.3 : 1
Power at 1/min	370 hp (276 kW) at 5800	430 hp (321 kW) at 5800
valve control	two overhead camshaftn / 2 valves per cylinder
mixture preparation	2 Weber-50-DCO Carburetor, Roots blower	2 Weber carburetors, dual Roots blower
cooling	Water
transmission	4 speed transmission, not synchronized (rear wheel drive)
brakes	Hydraulic drum braken on all wheels
Front suspension	Crank axle, coil springs, hydraulic shock absorbers	Cross arms, coil springs, hydraulic dampers
rear suspension	pendulum axle, transverse leaf spring, friction and hydraulic dampers	pendulum axle, semi-elliptical transverse leaf springs, hydraulic telescopic dampers, friction dampers
body and frame	Aluminum body on ladder frame
Wheelbase	2750mm	2800mm
Track width front / rear	1350mm / 1350mm	1370mm / 1430mm
front tire size	6.5 × 18	-
Rear tire size	6.5 × 19	-
Dimensions L × W × H	4200mm × 1520mm × 1215mm	4240mm × k. A × 1130 mm
curb weight (without driver)	820 kg	810 kg
tank capacity	170 l	-
fuel consumption	-	-
top speed	290 km/h (180 mph)	310 km/h (193 mph)