The Alfa Romeo 6C name was used on road, race, and sports cars produced between 1927 and 1954 by Alfa Romeo; the "6C" name refers to the six cylinders of the car's straight-six engine. Bodies for these cars were made by coachbuilders such as James Young, Zagato, Touring Superleggera, Castagna, and Pinin Farina. Beginning in 1933 there was also a 6C version with an Alfa factory body, built in Portello. In the early 1920s Vittorio Jano received a commission to create a lightweight, high performance vehicle to replace the Giuseppe Merosi designed RL and RM models. The car was introduced in April 1925 at the Salone dell' Automobile di Milano as the 6C 1500. It was based on Alfa's P2 Grand Prix car, using a single overhead cam 1,487 cc in-line six-cylinder engine, producing 44 horsepower. In 1928 the 1500 Sport was presented, which was the first Alfa Romeo road car with double overhead camshafts.
6C 1500 (1927–1929)
In the mid-1920s, Alfa's RL was considered too large and heavy, so a new development began. The 2-litre formula that had led to Alfa Romeo winning the Automobile World Championship in 1925, changed to 1.5-litres for the 1926 season. The 6C 1500 was introduced in 1925 at the Milan Motor Show. Series production started in 1927, with the P2 Grand Prix car as a starting point.The Alfa Romeo 6C-1500 Super Sport features a twin overhead cam six cylinder engine with a bore of 62 mm and stroke of 82 mm, giving a displacement of 1487 cc, as against the P2's 1,987 cc, while supercharging was dropped. First versions were bodied by James Young and Carrozzeria Touring.
In 1928, the 6C Sport model was released, with a dual overhead-camshaft engine. Its sport version won many races, including the 1928 Mille Miglia. Total production was 3,000 (200 with DOHC engines). Ten examples of a supercharged (compressore, compressor) Super Sport variant were also built.www.autoevolution Alfa Romeo introduced the 6C 1500 model in 1926, with series production beginning a year later. – Retrieved 2 January 2015
Specifications Model Years Crankcase/block/headconstruction Valvetrain Compr.ratio Fuel system Peak power Top speed Normale Alum./iron, monobloc SOHC 5.75:1 Single carburettor Sport 1928–29 Alum./iron/iron DOHC 6.0:1 Single carburettor Super Sport 1928–29 Alum./iron/iron DOHC 6.75:1 Twin choke carburettor Super Sport 1928–29 Alum./iron/iron DOHC 5.25:1 Single carburettor, supercharger Super SportTesta Fissa 1928–29 Alum./iron, monobloc DOHC 5.25:1 Single carburettor, supercharger
Production + Alfa Romeo 6C 1500, production by model Model 4-seater 6-seater Normale Sport Super SportCompressore Super Sport Total Series I I II II II II I–II Prod. years 1927–28 1927–28 1928–29 1928–29 1929 1929 1927–29 Prod. number 56 506 300 171 15 10 19276356000036219285015017015700527192900130141510169
6C 1750 (1929–1933)
The more powerful 6C 1750 (1,752 cc, 65 x 88 mm) was introduced in 1929 in Rome. The car had a top speed of , a chassis designed to flex and undulate over uneven surfaces, as well as sensitive geared-up steering. It was produced in six series between 1929 and 1933. The base model had a single overhead cam. Super Sport and Gran Sport versions had a double overhead cam engine (DOHC). Again, a supercharger was available. Most of the cars were sold as rolling chassis and bodied by coachbuilders such as Zagato, and Touring Superleggera. Additionally there were 3 examples built with James Young bodywork, one of which is a part of the permanent collection at the Simeone Foundation Automotive Museum in Philadelphia, PA, USA, in original and unrestored condition.
In 1929, the 6C won every major racing event in which it was entered, including the Grands Prix of Belgium, Spain, Tunis and Monza, and the Mille Miglia was won by Giuseppe Campari and Giulio Ramponi. The car also won the Brooklands Double Twelve and the Ulster TT. In 1930 the car again won the Mille Miglia and Spa 24 Hours. Total production was 2,635.
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6C 1750 GS Zagato/Aprile
The 1931 6C 1750 with license plate number "3710 SV" and chassis/engine number #10814331, which is currently owned by notorious rare car collector Corrado Lopresto, is a unique example, whose story is told in Lopresto's bilingual 2015 Skira book Best in Show – Capolavori dell'auto italiana dalla collezione Lopresto – Italian Cars Masterpieces from the Lopresto Collection.
The English-language section about this car tells:
A plush version of the car, manufactured by Vitale Barberis Canonico, was also given, together with the book, to some of Lopresto's friends.
Specifications Model Years Crankcase/block/headconstruction Valvetrain Compr.ratio Fuel system Peak power Top speed Turismo Alum./iron/iron SOHC 5.5:1 Single carburettor Sport 1929 Alum./iron/iron DOHC 5.75:1 Single carburettor 1930–32 Gran TurismoCompressore 1931–32 Alum./iron/iron DOHC 5.0:1 Single carburettor, supercharger Super Sport 1929 Alum./iron/iron DOHC 6.25:1 Twin choke carburettor Super SportCompressore 1929 Alum./iron/iron DOHC 5.0:1 Single carburettor, supercharger Gran Sport 1930–32 Super SportTesta Fissa 1929 Alum./iron, monobloc DOHC 5.0:1 Single carburettor, supercharger Gran SportTesta Fissa 1930–32 Gran Sport 1933 Alum./iron/alum. DOHC 5.0:1 Single carburettor, supercharger
Production + Alfa Romeo 6C 1750, production by model Model Turismo Sport Gran Turismo Gran TurismoCompressore Super Sport Gran Sport Total Series III, IV III IV, V IV III IV, V, VI III–VI Prod. years 1929–33 1929 1930–32 1932 1929 1930–33 1929–33 Prod. number 1,131 268 652 159 112 257
6C 1900 (1933)
The Alfa Romeo 6C 1900 was the final derivative of the original 6C 1500, produced in 197 examples during 1933 as a transitional model, before the new 6C 2300 was introduced the following year. Only built in Gran Turismo guise with a wheelbase, the 6C 1900 replaced the corresponding 6C 1750 model. Besides the larger displacement, other notable mechanical changes were aluminium cylinder heads, an improved chassis frame and a new transmission. The same upgrades were applied to the 1933 model 6C 1750 Gran Sport which, together with the 6C 1900, form the sixth series of the 6C. Alfa Romeo offered the 6C 1900 with an in-house 4-door saloon body, while bespoke coachbuilt body styles included 4-seater cabriolets.
The double overhead camshaft, naturally aspirated, straight-six engine was bored out from to , bringing displacement to . For the first time on a 6C the cylinder head was aluminium; some engines were also manufactured using an aluminium block with pressed-in steel sleeves in place of the usual cast iron block. With the 6C 1900 could achieve a top speed of . The improved chassis frame consisted of fully boxed rails and crossmembers, instead of the 1750's C-shaped sections. A new four-speed gearbox was fitted, with synchromesh on the two top gears and a freewheel mechanism.
Specifications Model Years Crankcase/block/headconstruction Valvetrain Compr.ratio Fuel system Peak power Top speed 1933 Alum./iron/alum. DOHC 6.25:1 Single carburettor
Production Alfa Romeo 6C 1900,production by model Model Gran Turismo Total Series VI VI Prod. years 1933 1933 Prod. number 197 197
6C 2300 (1934–1938)
The 6C 2300 (2,309 cc, 70 x 100 mm) was designed by Vittorio Jano as a lower-cost alternative to the 8C. In 1934 Alfa Romeo had become a state-owned enterprise. That year, a new 6C model with a newly designed and larger engine was presented. Chassis technology, however, had been taken from the predecessor. One year later a revised model, the 6C 2300 B, was presented. In this version the engine was placed in a completely redesigned chassis, with independent front suspension and rear swing axle, as well as hydraulic brakes. 760 examples of the rigid-axle 6C 2300 were produced and 870 examples of the B-model.
Specifications ModelEngineMax powerFuel systemTop speedYearsNumber produced6C 2300 Turismo DOHC I6 at 4,400 rpmsingle carburetor19346C 2300 Gran Turismo DOHC I6 at 4,400 rpmsingle carburetor19346C 2300 B Gran Turismo DOHC I6 at 4,400 rpmsingle carburetor1935–19386C 2300 Pescara DOHC I6 at 4,500 rpmdouble carburetor1934 606C 2300 B Pescara DOHC I6 at 4,500 rpmdouble carburetor1935–1938 1206C 2300 B Corto/Lungo DOHC I6---19356C 2300 B Mille Miglia DOHC I6---
Year193419351936193719381939Sum6C 2300 Tourismo1992600002256C 2300 Gran Tourismo4532000004736C 2300 Pescara40200000606C 2300 B Gran Tourismo01607000866C 2300 B Pescara035112001206C 2300 B Torismo0007800786C 2300 Mille Miglia000010701076C 2300 B lungo0000217292466C 2300 B corto000019813211Sum69285 5260 522 421,606corto et lungo = short and long
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Aerodinamica Spider
The Alfa Romeo Aerodinamica Spider was a one-off mid-engine streamlined prototype, built by brothers Gino and Oscar Jankovitz in connection with Alfa Romeo between 1935 and 1937 in Fiume (today Rijeka), and should have been powered by an Alfa Romeo 12-cylinder engine. The construction of the car took many years, while technical changes had to be made due to the testing period from 1936 to 1937. The Aero. spider represents: The first “modern” mid-engined sports car design.Klassiekerweb: Alfa Romeo 6C 2300 Aerospyder - Klassiekerweb, access-date: 26. October 2018 The first mid-engined car with central driving position (albeit Lancia deposited a patent for a centrally driven design in 1934). The first car designed to take account of newly developed principles of aerodynamics, to provide low drag both externally and internally. The first car which was designed for high speeds, by using a body which fully enveloped the underside of the car to reduce air turbulence beneath it and an aerodynamic front design to reduce front lift of the car
History Between 1935 and 1937 the Jankovits carried out the construction; a "rolling chassis" could be registered in Fiume (number plate: 2757 FM) tested, and subsequently modified.
The No.700316 6C 2300 Tipo Turismo straight-six engine placed behind the driver was Alfa Romeo: 2,309 cc, iron block, light alloy head, chain-driven dual overhead camshafts, spur gears, wet sump lubrication. The Jankovits fitted exhaust pipes of equal length and improved intake of air to reduce the pressure drop. Later the engine was upgraded with three dual Weber 36 D 04 carburettors, a configuration used on the 6C 2500 SS of 1939. The transmission was the 4-speed gearbox from the 6C 2300, mounted with a Hardy disc behind the engine originally fitted, which they removed. A differential unit from a Lancia Lambda was later fitted instead. A unique pre-selector gear change system was also developed. The clutch was hydraulically assisted.
The ladder chassis was made by Alfa Romeo for the central-mounted engine, with straight rails from front to the rear end of the car; it was numbered 700316 in accordance with the engine number. The final suspension was all-independent, with "silent bloc" bushes; at the front it consisted of double wishbones, with a thick sheet steel (4 mm) upper wishbone, lever-arm Houdaille shock absorber hydraulic dampers, longitudinal torsion bars, and lower location through a transverse leaf spring; at the rear it had swing axles and radius arms, with a transverse leaf spring and longitudinal torsion bars.
Steering was worm and sector with Hardy disc. Brakes used a two-circuit hydraulic system (two fluid distributors and two master cylinders, one for the front and one for the rear), Lockheed-type duplex brakes with drums all round. An equaliser was fitted, which could avoid overbraking by changing the distribution of braking force between the front and rear brakes during driving. 5.50–18 racing crossply tyres were mounted on Alfa Romeo 18-inch Rudge-type wire wheels.