Audi F103

Audi F103
Audi 75
Overview
Manufacturer	Auto Union GmbH, Audi NSU Auto Union AG (1969–1972)
Production	September 1965 – July 1972 416,853 built[1] of which: Sedan/Saloon: 386,361 Variant (station wagon/estate): 27,492
Assembly	Ingolstadt, Germany
Body and chassis
Class	Compact executive car (D)
Body style	2- or 4-door saloon 3-door estate
Layout	Longitudinal front engine, front-wheel drive
Powertrain
Engine	1.5–1.8 L inline-4
Transmission	4-speed manual
Dimensions
Wheelbase	2,490 mm (98 in)
Length	4,380 mm (172 in)
Width	1,626 mm (64.0 in)
Curb weight	960 kg (2,120 lb)−1,065 kg (2,348 lb)
Chronology
Predecessor	DKW F102
Successor	Audi 80

F103 is the internal designation for a series of car models produced by Auto Union GmbH (after merger with NSU Motorenwerke in 1969: Audi NSU Auto Union) in West Germany from 1965 to 1972, derived from the earlier DKW F102. To signify the change from a two-stroke to four-stroke engine, the DKW marque was dropped in favour of Audi, a name dormant since before the Second World War.

Models

The first model was launched simply as the Audi, later being renamed the Audi 72 (72 being the nominal power output of the engine in Pferdestärke), also known as hp/m.

The more powerful Audi 80 and Audi Super 90 sports saloons appeared in 1966: in 1968 the arrival of the less powerful Audi 60 completed the range.

The Audi 75 replaced both the Audi 72 and the Audi 80 from 1969 onwards.

In 1972 the F103 series was discontinued in favour of the "B1" Audi 80.

Engines

The F103 series were equipped exclusively with four-cylinder four-stroke engines. These were longitudinally mounted. This combination of front-wheel drive, which Auto Union's DKW brand had pioneered during the 1930s, and the longitudinal positioning of a four-cylinder engine would provide the basic template for Volkswagen's successful new Passat as well as the Audi models Audi 80 and Audi 100 after Volkswagenwerk AG acquired the Auto Union from Daimler-Benz late in 1964. Since the chassis on the F103 was taken from the DKW F102 with a 3-cylinder two-stroke engine, the longer engine meant that the cooling system had to be offset to the left of the engine instead of the normal position in front of it. Because of the radiator’s location, the front cylinder of the engine had a tendency to run cooler than the other three and as a consequence the spark plug tended to foul up, particularly if the engine was often used in city traffic. To avoid this, it was often recommended to run a hotter spark plug (with a lower heat range) in the front cylinder than in the other three.

1966 Audi two-door saloon

The engines of the F103 series were a development of Daimler-Benz for a military project that never came into being. They were dubbed the Mitteldruckmotor (medium-pressure engines) because of their unusually high BMEP (mean effective pressure, as calculated from brake torque) values, which led to a good thermodynamic effiency. The engines had spiral-formed intake channels that gave the fuel-air mixture a good swirl. The engine had Heron-type combustion chambers with broad squish bands, further enhancing the mixture swirl and aiding good combustion. These features made it possible to use very high compression ratios for the time. The initial engine version had a CR of 11.2 to 1 for 98 RON fuel and even the engines intended for 92 RON fuel had a CR of 9 to 1, which was a very unusually high value for the time.

Running gear

The car came with a four-speed manual transmission.

Inboard mounted front disc brakes were featured,^[2] which was still unusual in the mid-size car market at this time. The rear brakes followed the more conventional drum configuration.

Bodywork

The form of the Audi F103's body closely followed that of the earlier DKW F102, shown here, though the Audi's engine was a break with the two-stroke DKW tradition.

The F103 bodyshell was a development of the earlier DKW F102. The engine compartment had to be extended so that the new four-cylinder engine could be accommodated. The front and tail were also cosmetically revised: Audi F103s sold in Europe all featured quasi-rectangular headlamps which were becoming fashionable at the time, whereas the F102 had used round headlamp units.

All Audi F103 models were offered as sedans with two and four doors. The two-door saloon/sedan, however, was not sold in markets such as Italy and Britain with little demand for two-door cars of this size.

With the exception of the Audi Super 90, the F103 series were available also as three-door station wagon models. Making its debut at the Geneva Motor Show in March 1966,^[3] this was called, like the Volkswagen estate/station wagon models, Variant.

Evolution

Initial changes were concentrated under the hood/bonnet where during the first two years of production the specification for the Solex carburetor was changed twice and in September 1967 the very high compression ratio was reduced from a (then) eye watering 1:11.2 to 1:9.1 which addressed serious "teething problems" with the engine as originally launched.^[4]

In September 1967 servo-assistance for the brakes became an option, the brakes on all but the basic model now being controlled using twin braking circuits, and by (in Germany) the final months of 1968 the range had settled down to three models, with the entry level Audi 60 powered by a 55 PS motor, the less basic Audi 75 producing 75 PS and the Audi Super 90 with 90 PS, able to challenge the performance image of some of the smaller BMWs.^[5]

Visually the car changed very little, but keen eyed observers would have noticed a discreetly modernised rear from August 1970, with slightly larger rear lights and a reshaped bumper. The fuel filler moved from its location to the right of the license plate on the rear panel to a position on the right hand wing of the car, and following a general trend of the period was now shielded by a flap that was flush with the bodywork. Inside the 1970 upgrade also involved a reconfigured dashboard.^[6]

Commercial

During the early 1960s, Auto Union was in commercial retreat: the Audi F103 was a relative success when compared with recent Auto Union products, even if its commercial success was trumped by subsequent Audi models. In July 1967, it was reported that 100,000 Audis had been completed:^[2] production of the F103 had by now built up to a rate of almost 40,000 per year and the company was moved to deny speculation that another new Audi model would be presented at the Frankfurt Motor Show in the Autumn / Fall of 1967.^[2] (The Audi 100 was introduced only towards the end of 1968.)

Specifications

Manufacturer's figures except where stated^[1]

Audi F103	Audi 60 2- or 4-door saloon/sedan 3-door 'Variant' estate/station wagon	Audi 72 2- or 4-door saloon/sedan 3-door 'Variant' estate/station wagon	Audi 75 2- or 4-door saloon/sedan 3-door 'Variant' estate/station wagon	Audi 80 2- or 4-door saloon/sedan 3-door 'Variant' estate/station wagon	Audi Super 90 2- or 4-door saloon/sedan
Produced (years):	1968–1972	1965–1969	1969–1972	1966–1969	1966–1972
Produced (units – excludes estate 'Variant' bodied cars):	216,988	122,579			49,794
Engine:	4-cylinder-inline engine (four-stroke), longitudinally front-mounted
Bore x Stroke:	80 x 74.4	80 x 84.4			81.5 x 84.4
Displacement:	1496 cc	1697 cc			1760 cc
Max. Power:	55 PS / 54 hp / 40 kW 65 PS / 64 hp / 48 kW	72 PS / 71 hp / 53 kW	75 PS / 74 hp / 55 kW	80 PS / 79 hp / 59 kW	90 PS / 89 hp / 66 kW
Compression Ratio:	9.1 : 1	11.2 : 1[7]	9.1 : 1	–	10.6 : 1
Acceleration 0 – 100 km/h / 0 – 62 mph (seconds):	18.0	14.8	14.5	14.0	12.2
Max Speed km/h (mph) :	138 km/h (86 mph) 144 km/h (89 mph)	148 km/h (92 mph)	150 km/h (93 mph)	152 km/h (94 mph)	163 km/h (101 mph)
Fuel feed:	single Solex carburetor
Valvetrain:	–
Cooling:	Water
Electrical system:	12-volt
Front suspension:	Independent torsion bar
Rear suspension::	Torsion bar
Brakes:	Front discs / Rear drum brakes
Body structure:	Monocoque
Dry weight:	960 kg (2,120 lb) – 1,065 kg (2,348 lb)
Track front/rear:	1,343 mm (52.9 in) / 1,327 mm (52.2 in)
Wheelbase:	2,490 mm (98 in)
Length:	4,380 mm (172 in)
Width:	1,626 mm (64.0 in)
Height:	1,451 mm (57.1 in)
Steering:	rack & pinion
Turning circle:	10.59 m / 34'9"[7]

References

1. Oswald, Werner (2001). Deutsche Autos 1945–1990, Band 4 (1. ed.). Stuttgart: Motorbuch Verlag. ISBN 3-613-02131-5.
2. "Exhibition Stand 107 Auto Union". Autocar. 127. Vol. (nbr 3740). October 1967. p. 28.
3. "36th Geneva Salon". Autocar. 124. Vol. (nbr 3657). 18 March 1966. pp. 540–546, 581.
4. Oswald, Werner (2001). Deutsche Autos 1945–1990, volume 4 (in German). Motorbuch Verlag. p. 264. ISBN 3-613-02131-5.
5. Oswald, Werner (2001). Deutsche Autos 1945–1990, volume 4 (in German). Motorbuch Verlag. pp. 266, 267. ISBN 3-613-02131-5.
6. Oswald, Werner (2001). Deutsche Autos 1945–1990, volume 4 (in German). Motorbuch Verlag. p. 265. ISBN 3-613-02131-5.
7. Cardew, Basil (1966). Daily Express Review of the 1966 Motor Show. London: Beaverbrook Newspapers Ltd.

External links

• Good overview of the development of the DKW F103 to the Audi 60 (in German)
• A Super 90 at a vintage rally
• Website Audi60.com