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The Return of the Twin

Fiat TwinAir engineThe twin cylinder engine that has prompted me to look into the history of the twin cylinder automobile engine is the Fiat TwinAir.
The Fiat TwinAir engine, available in some Fiat 500, Panda, and Alfa Romeo Miti's, uses an innovative valve gear technology to optimize performance and efficiency.
With only two cylinders with a total capacity of only 875 cc. and when turbocharged it produces 84 bhp.This in conjunction with an emission level of only 92g/Km, makes it outstanding and a pointer to future engine developments.
Its appropriate that the TwinAir, is produced by Fiat, as they had produced over four million twin cylinder engined cars since 1957.
The TwinAir is in no way related to those previous twins. These first of previous twins were produced for the rear engined 500 Nova, in 1957. An air-cooled parallel twin with a capacity of 479 cc, producing 17 bhp. In 1972 the 500, was joined by the 126, with a similar engine of 594 cc, reducing 23 bhp. This was produced until 1987, the 500, had been discontinued in 1977. The final Fiat twin, was 704 cc, water-cooled unit, producing 26 bhp. First fitted in the 126bis, produced from 1987 to 1992. This engine was available as an option in some markets in the Cinquecento 700, model, produced between 1992 and 1998.

The  Return of the  Twin Cylinder  Engine into Mainstream Motoring.

Since 1998 until the advent of the TwinAir, the twin cylinder engined car has been missing from the mainstream manufacturers showrooms. Historically this was not normally the case, as twins have been produced from the beginning of the motoring era, with fourteen and a half million produced between 1948 and 1998, being a major component of the economy car sector in Europe in that period.
With a few exceptions the twin has been the preserve of the lighter end of the automobile spectrum. Used first in the pioneering cars, the in Voiterettes, followed by the so called cycle cars of the first part of the last century. Finally by the Mini and Micro cars of the middle and later part of the century. Ofter considered the poor relation of the small four cylinder engine the twin cylinder engine has been of great service to many millions of the worlds motorist.

Time line
The Veteran Era. The first twin's were produced almost at the beginning of the motoring age by amongst others the greatest pioneers, Daimler, Ford and Benz.
Daimler V twin1889. The first Daimler twin designed by Wilhelm Maybach was of a narrow"V" configuration, with a capacity 565 cc, and produced 1.5 hp.
A licensed version of this engine was used by Peugeot.
1891. Panhard and Levisour used and engine of this design in their innovative front engined car, with the clutch and gearbox behind with chains to the rear wheels, starting a fashion that was to be dominant for the next sixty years and was the transition from the horseless carriage to the automobile.
Ford quadicycle1896. In the USA Henry Ford used an in line or parallel twin, with the cylinders lying horizontally, producing three horsepower, for his Quadricycle. He made a total of three of these, the last in 1901. Other twin's that Ford produced, were the first Model A 9hp, in 1903, the Model B, in 1904 and finally the Model F, produced between 1905 and 1906.
Lanchester1896. In England Dr Fred Lanchester designed a car with many original features. Amongst them was a twin cylinder engine of unique design. This engine was different from all other twins made before or since, in having four connecting rods to connect the two pistons to two crankshafts, with the aim of producing perfect balance. This was attained but at high cost. Engines of this layout were fitted to Lanchester cars produced between 1906 and 1908. With a capacity of 4106 cc, producing 12 horsepower running at 760 rpm. By then engines of this size had four or more cylinders and this line of development was not repeated.

Daimler Parallel twin1897. Daimler fitted an 1060 cc, water-cooled in line or parallel twin cylinder engine with the cylinders upright, in their "Phenix model, which was still very much a horseless carriage.

1897 PanhardPanhard engine1897. Panhard et Levassor produced a front engined design fitted with a Daimler Phenix twin cylinder engine of 1206 cc, producing 4 hp, at 800 rpm, It had a cruising speed of 10 mph. §§
Mors engine1899. Mors produced the "Petit Duc"' model with a 4 hp, twin cylinder horizontally opposed engine with air-cooled cylinder barrels and water-cooled heads.
1899. Benz produced a 1728 cc, horizontally opposed water-cooled twin named the "Contra engine"  that produced  five horsepower at 920 rpm.  This was fitted at the rear of the car.
              decauville1899. The Decauville Voiturelle, had a 479 cc, vertical twin mounted in the rear, it produced 3 hp, at 1,200 rpm.

The "V"usually at 90 degree's, the parallel twin, usually upright, and the horizontally opposed,
were the three configuration commonly used for twin cylinder engines, with only rare variations such as the Lanchester utilized.    

1900 Daimler
              PD1900. Paul Daimler the son of Gottleib Daimler, created a very significant design the Daimler PD. It had a 4 hp, 1230 cc twin cylinder engine of 86 mm bore and 116 mm stroke with automatic inlet valves and low tension ignition. 40 kph was attained at 850 rpm. The engine was at the front with an integral gearbox and the PD was seen as the fore-runner of the light car and was the inspiration for the next Daimler model the Mercedes prototype of 1901.

Renault AG1902. Renault Twins.
The earliest Renault models all vouterettes, had been fitted  with a De-Deon single cylinder engines. The Type H14cv of 1902, was the first model to be fitted with an engine manufactured by Renault. This was a water-cooled side-valve inline twin of 1728 cc. producing 14 bhp. at 1200 rpm. A later version of this engine fitted in the Model J. had a capacity of 2280 cc and the Model J. had a top speed of 74 kph. The engines fitted to the H and J models had an automatic inlet valve. The 10/16 cv of 1903 had mechanically operated overhead and side exhaust valves and produced 16 bhp from a capacity of 1885 cc. One of the most famous Renault models was the Type AG 8 cv. of 1905. Fitted with a 1060 cc. water-cooled side-valve twin cylinder engine producing only 8 bhp. The 8 cv. was used as the premier Paris taxi, to well after the first World War, and came to fame as the "Taxi De La Marne"', being used to rush troops to the front in 1914 and saving Paris from being over run by the invading German army. Renault's last twin's were the AX 7/8cv. and  8/9cv of 1909.  A later model using the 1060 cc. engine and a 1205 cc. larger version.  They were produced until 1914.

Arrel-JohnsonGebron engine layout1905.  Two makers during the veteran era, used twin cylinder engines with two pistons per cylinder,  One of them was the Scottish maker Arrel-Johnston. A chassis is shown at the left. They used rocking arms to connect the connecting rods to the crank. The other was the French manufacturer Gebron-Brillie who's arrangement is shown in the drawing. Arrol-Johnston produced a twin until 1909, Gebron-Brillie until 1912.

Edwardian twins list1AlbionEdwardian Era. During the Edwardian era thirty percent of the numerous British, European and American manufacturers  produced twins.
Twins dominated the eight to ten horsepower classes. with 165 models in that range In comparison, in the same period, only 74 four cylinder engined models were on offer. A total of 330 twins were offered for sale during the period 1906 to 1914. The larger models were mostly produced in the early years of the era. Most larger twins had been discontinued by the end of the first decade of the twentieth century.

The Albion 16 hp. was an example of the large  twin cylinder engined cars of the Edwardian era. On sale from 1906 to 1913, by which time most engines of this size had at least four cylinders.
The list on the left shows it to be exceptional, the majority being in the 8 to 10 horsepower range. 

Albion engine  

A List of twins on sale in the Edwardian era.
Edwardian twins list 29 hp Gregoire 1906 Gregoire 8 h.p. (two-cylinder)
Automobiles Grégoire, more simply known as Grégoire, was a French car manufacturer. Established on the Boulevard Devaux in Poissy. Gregoire started off by manufacturing engines in 1903.
In 1904, the company started to manufacture automobiles. The design was considered nothing special, but was easily recognizable by its pear-shaped radiator. The company made cars with single,
two and four-cylinder engines.

1907 Riley1907.The Riley 9 hp  was the first four wheeled car produced by the company. It had a 1034 cc. water-cooled V twin engine. It was produced from 1907 until 1911. They also produced twin's. The 12/18 hp. with a 2039 cc. engine from 1907 until 1914, and a 10 hp. from 1909 until 1914. Both with Riley patent side valves.

1908 Humber 81909. The first engine produced by Humber in 1902 had twin cylinder's, and they had produced various twins since then.the 8 hp. of 1909/10, was the largest at 1527 cc. and the last of what be considered full size cars at the time. The last twin cylinder engined car produced by Humber was the Humberette of 1913 to1915, which was a 998 cc. air-cooled V twin, and classed as a cycle car, although  other than the engine it was conventional and in no way crude.

Edwardian twins list3Humber 8 engine

Jowett 6.4hp1910. In Bradford, Yorkshire, William and Benjamin Jowett had been developing their 6.4 hp car since 1906. In 1910 they decided to start manufacturing cars for sale.  The car had a water-cooled, side-valve, horizontally opposed twin cylinder engine of 822 cc. They produced less than fifty cars by 1914, but the engine would remain in production for forty three years installed in thousands of cars and commercial vehicles mostly sold locally, the last produced in 1953.

Adler 7 hp
Adler the German car maker produced a number of light twins after 1907 . The last to be introduced was the 7 hp. with a 80 mm X 100 mm. engine in 1910.

Edwardian twins list 4Lion Peugeot1911. Marketed in Britain, as the Lion 12. and the Lion 16. They were made in France by the Lion-Peugeot branch of the company and were the last of Peugeot twins, in production until 1912. The other part of Peugeot had produced larger twins from 1906 until 1911.

Perry 81912. The Perry Motor Company Limited, of Tyseley, Birmingham, was formed in 1912 and the first model they produced was the "8". It had a 878 c.c. (72 mm. x 108 mm.) water-cooled, parallel twin cylinder engine. It had three speed gearbox and a worm drive rear axle. In 1914 it was priced at £147. The "Eight". was produced until 1915.

Perry chassis

Edwardian twins list 6Swift1913. Apart from a few old designs that would soon be discontinued, the twin was becoming the engine of choice for the new ultra light cars at that time designated cycle cars. The Swift was one example. They had been making  twin since in 1906 in large engine sizes.

1913 Alday Others were the Alday Midget 8/10.  Aldays had also been making twins since 1906 but would survive until the early 1920's.

Chater-Lea engine Chater-Lea were newcomer's with the Chater-Lea 8/9. This was the water-cooled version of the 8/9 engine. An air-cooled version was also available.

Edwardian twins list 7GWK1914. Two very different British light cars were on sale in Great Britain in 1914 when production of cars stopped due to to the war. When peace came in 1918, they were soon back in production, but only for a short while as car design had moved on.

GWK ChassisThe GWK 8 hp. was produced from  1912 to 1919, and was of unconventional design. Its two cylinder Coventry Simplex. water-cooled engine that was located in the centre of the car. The transmission consisted of a variable ratio friction drive, with a live rear axle. Friction drive had very short period of use in very cheap cars in the 1920's.

Buckingham adThe 12 hp Buckingham was typical of the twin cylinder light cars in Britain in this period, with a mixture of car and cycle car design features.
It had a 89 mm X 88 mm. 1095 cc.overhead-valve, air-cooled engine.
Up to fifteen cars a week may have been produced until the war intervened. Alvis took up the design after the was with little success.
Buckingham engine

The Nineteen Twenties
By 1918 the multi cylinder engine with from four up to in a few cases, twelve cylinder was the normal in fitment in the majority of cars offered for sale. The twin cylinder engines  was now only fitted to cycle cars and economy cars and at that time all were lumped together under the definition of cycle car.

The true cycle car was at the very cheapest end of the car price range and can correctly defined as a ultra light cars using motorcycle technology to attain that lightness. The GN and the Morgan three wheelers are well known examples and both had V twin engine of various make installed in them, with multi chain final drives that were used in place of a gearbox.

1922 GN Vitesse1920 Morgan family Model

A 1922 GN Vitesse showing the chain final drive.   1920 Morgan family model.

The twin cylinder Economy car in Britain would have a brief period of popularity between 1918 and 1925. Only one of the pre-war designs the Jowett 8, returning to production, soon to be replaced successive models until 1940, all with a twin cylinder engine. The four cylinder engined economy cars had been available before the war, but were more expensive than the twins. It was the Austin Seven, that could match them on price and exceed then on refinement that led to the demise of the twin in Britain.

        Jowett1922 Rover 8ABC 12hp

1919. Jowett 8                                                 1919/25. Rover Eight                                             1920/27 ABC 12 hp 

Granville Bradshaw designed advanced aero engines for the ABC company during the first World war.  At the war end development was stopped and government contracts terminated, so Bradshaw designed a light car to help fill the gap. It had an air-cooled, horizontally-opposed, overhead valve, twin cylinder engine of 1203cc.  The Harper-Bean Ltd became interested in the project and ABC Motors (1920) Ltd was formed. As the fortunes of the Harper-Bean company faltered, so did ABC Motors . Only about 1500 examples were produced in seven years. A 1320cc Super Sports version made in small numbers, added a bit of glamore to what was an unrefined noisy car.
BSA 10Stoneleigh 9

1921/25. BSA 10.                                                      1921/24 Stoneleigh 9hp.

Bradshaw 91921. Granville Bradshaw was a controversial designer. He had designed motorcycles with air-cooled engine for ABC before the war  and after the war also the car mentioned above, and advanced air-cooled radial aero engines for the British government during the war. these designs were ahead of their time and in service proved unreliable. The 9 hp. Belsize Bradshaw was a conventional light touring car, except for Vee twin  1289 cc. later 1370 cc. side-valve, fan-cooled engine that had a large oil capacity that helped dissipate the heat of the engine by distributing it all around the engine, using all of the engine structure for cooling purposes. It was produced from 1921 to 1924 when anything between seven hundred and fifty and one thousand five hundred were produced.

Belsize Bradshaw engine

Wolseley StelliteAriel NineMatchless Model K
1922/23 Wolseley Stellite 7                                1922/25 Ariel Nine                              192224 Matchless Model K

In 1922 the motorcycle makers H Collier and Sons, began production of their Model K economy car. It had 1.35 litre overhead valve, air-cooled, twin cylinder engine. The drive train was conventional for the period but the unitary chassis/body and the independent front suspension was not. it is believed that only 50 were produced by the time production ceased in 1924.

The twin cylinder engined economy cars in the 1920's was a very British thing, being only being fitted in cyclecars in Europe such as the Sima Violet. There were two exceptions, one was the Tatra T11manufactured in Czechoslovakia and other the DKW P15, from Germany.

Tatra T11 engineTatra T11/12

A Tatra T12

1923. While working at Steyr Hans Ledwinka had been creating the design of a small car in his own time. His design had been rejected by the Steyr, management, but he was able to develop and produce this design after he left Steyr in 1923 to work for Tatra. Designated the Tatra T11 it made the name of Tatra well known throughout Europe. The T11 was the first of his designs using a backbone chassis, a fan cooled horizontally opposed engine  and a jointless independent rear axle. The engine in this design was a overhead valve 1056cc twin, mounted in unit with the gearbox on the front of the chassis. The front beam axle being attached to the engine.
This was the first of a line of light car design’s to a similar pattern that were produced until 1948. The T11 was produced from 1923 to 1927, and replaced by the T12 with a similar specification. The T12 was produced from 1926 to 1936.

Drawing of the Tatra T11 engine

DKW P15In 1928 DKW  of Zwickau, Germany, made the first in a line of inline vertical twin cylinder two-stroke cars the P15.  It differed from all the later twins in having rear wheel drive. The P15 had only two seats which was common for economy cars of the period, as the 584 cc engine only produced 15 bhp. Its layout and construction was conventional for the period with a live rear axle, a beam front axle, transverse leaf springs , a steel chassis frame with a wood paneled body. About 2000 P15 and the related PS600 sports model were produced between 1928 and 1930.
Its significance is that, a two-stroke twin cylinder car in one form or another, would be in production in some part of Germany from 1928 to 1990.

                                                                                                                                A DKW P15

Rover ScarabIn 1929 Colonel Frank Searle the managing director of the Rover Co Ltd of England decided that the company needed a small car to widen its range. He set Maurice Wilks and Robert Boyle, both to become key figures at Rover, to design and produce a prototype of a small rear engined car at his home Braunston Hall near Rugby in a similar way that Herbert Austin had done with the Austin Seven earlier in the decade. The outcome of their work the Rover 7 HP or Scarab was unlike any previous Rover design with a Rover Patented engine, transmission and rear suspension layout. The rear mounted O.H.V fan-cooled 60 degree "V" twin engine was of 839 cc. The ladder frame chassis was of advanced design with coil spring sliding pillar front suspension and coil spring swing axles at the rear with a pivoting support member giving zero roll stiffness. The four-seat tourer body was a simple affair of wood framing clad with steel sheet of compact dimensions, the car being designed down to a price of  £85. Unfortunately the engine proved to be rough, noisy and prone to overheating. With the departure of Colonel Frank Searle from Rover in 1931 the Scarab didn't go into production as it was considered too radical and at the same time too Spartan by the Rover management.

The Nineteen Thirties
Jowett 8HP
1930. At the beginning of the decade, there was only one twin cylinder engined four wheel car produced in Britain, that was the Jowett 7 HP. It was a product of evolution with a specification similar to other small car of the period except for the engine, which was an evolved version of the earlier Jowett twin. The 7HP was produced from 1930 until 1936 when it was replaced by the 8HP,the last Jowett twin cylinder car. A further evolved model again mirroring the style and construction of its contemporary's. Production of the 7HP amounted to 11,444 examples and the 8HP. 2,888. 

A 1937 Jowett 8HP

DKW FA1931. The DKW FA was the first in a long line of DKW twin's that would influence many other makers designs  for the next sixty years. The difference between the P15 and the FA was the drive train, the FA having front wheel drive. The FA 's transmission layout, was as common practice at the time on front wheel drive cars, with the with final drive at the front, next came the gearbox and at the rear the engine. DKW FA
      power unitThe difference was the transverse engine/gearbox installation. The 490cc engine produced a modest 15 bhp giving it a maximum speed of 47mph (75 kph). The suspension was as innovative as the transmission being independent using twin transverse leaf springs front and rear of the ladder type chassis.

DKW FA Power train                                                                               A DKW FA
Aero 662

In Czechoslovakia the Aero company produced their first twin cylinder car the Aero 662. The 662cc, water-cooled, two-stroke, inline vertical twin cylinder engine was located at the front of the leaf spring suspended chassis, driving a three speed gearbox, then a live rear axle without a differential. It was produced from 1931 until 1934 with a production total of 2,615. Between 1933 and 1934 Aero produced the Aero Type 20, with 998cc engine producing 28 bhp. Two thousand five hundred and forty six were made.

                                                                                                                                                     An AERO 662 saloon

BSA FW321932. The only other British twin of the 1930's was the BSA FW32 which was only produced in 1932 with 100 made.. It was a four wheeled version of the BSA Three-Wheeler Twin of 1930. Both models used an air-cooled V twin of 1021cc, based on a Hochkiss design that drove the independently sprung front wheels. The three wheeled version was produced from 1930 to 1936.


1933. In Czechoslovakia Tatra produced a rear engined prototype the V570, with an air-cooled, OHV, horizontally opposed twin cylinder engine, but it was not put into production.
Standard Superior

                                        A Standard Superior

In Germany Standard Fahrzeugfabrik began manufacturing the Standard Superior. It was based on the designs of Josf Ganz. It had 396cc horizontal parallel  twin two-stroke water-cooled engine located on the backbone chassis just ahead of the rear swing axles which it drove.  From 1928 onwards, the idea of a people's car with a rear mounted air-cooled engine, all independent springing and a backbone frame was promoted in Germany by an engineer and journalist Josef Ganz. Ardie a German motorcycle manufacturer produced an experimental car with a forked backbone frame the Ardie Ganz, in 1930. Adler a German manufacturer produced another Ganz prototype in 1931. In 1933 the first of his designs to go in production was the Superior. It cost RM1590, or £78 at the 1935 exchange rate.                                                                

Hansa 500At  the motor show in 1933 in Berlin Carl F.W. Borgward presented the new car "Goliath Hansa 400". It was fitted with 2 cylinder ILO engine of 396 cc that produced 12 HP.
In the end of 1933 it was joined by the  Hansa 500, which was equipped with a 2 cylinder ILO engine of 494 cc that produced 14 HP.
The maximum speed's were 40 and 44 mph respectively. In 1934 a convertible saloon was also produced. The purchase prices lay according to version between 1650 and 1720 Reichsmark.

A Hansa 500

Bungartz ButzBungartz Butz chassisTowards the end of 1933, Dr. Everhard Bungartz, director of the newly established company Bungartz & Co., contacted Josef Ganz because he wanted to develop and build a small car according to his patents.
Technically the new Bungartz Butz model was very similar to the Standard Superior, introduced one year earlier. It featured a tubular chassis, a mid-mounted engine, and independent wheel suspension with swing-axles at the rear.
The Bungartz Butz was available in two basic versions: the Butz Cabrio-Limousine and the Butz Touren-Wagen. Both versions were two-seaters. The Butz had a plywood body covered in artificial leather and fitted with metal wings. Unfortunately, only few copies could be sold from the year 1933 to 1934.
                                                                                                                                                       A Bungartz Butz

        F5 MeisterklasseThe DKW front wheel drive series of cars were produced throughout the nineteen thirties in a range of models with the names F2, F4, F5, F7, and F8, combined with, Reichklasse, Meisterklasse and Meisterklasse Luxus in various combinations. They  began producing the F-2 Reichklasse, with a fabric covered wooden body in 1932 . The engine as fitted to the FA was now increased to 584 cc, producing 18bhp, and from 1933 the engine had been redesigned to incorporate the idea's of Adolf Schnrle to improve the porting. Approximately 17,000 were produced by 1934.  In 1934. they introduced a revised model the F4. The engine was now increased to 692cc,  the spur gear primary drive to the gearbox was replaced by a chain.  The F5 Meisterklasse with a 692cc engine and the F5 Reicksklasse with a 584cc engine, now with a dead rear axle, were produced between 1935 and 1936 with 60,000 produced. The F7 with the same two models was made from 1937 to 1938, with 80,00 produced. The final model of the 1930's was the F8 Reichsklasse, with a 589cc engine was made from 1939 to 1942 with 50,000 produced.     
 A F5 Meisterklasse Luxus    

Jawa 700

In the same year Jawa was a Czech motorcycle manufacturer, they began car production at this time with the Jawa 700. It was similar in design if not bases on the current DKW and was produced from 1934 to 1936. Jawa also made the 600 Minor , similar in design to the 700.
                                                                                                                                                 A Jawa 700

With the onset of war in Europe in 1939, as the military had no use for economy cars production came to a stop as factories were converted to arms manufacturing, not to be resumed until well into the next decade.

1939 Crosely

Across the Atlantic, war didn't come for another three years with car production carrying on as usual. In 1939 production began of a small economy car, completely alien to the USA, the Crosely. Industrialist Powel Crosley, Jr., of Cincinnati, Ohio, owner of Crosley Broadcasting Corporation  developed an ultra light car for the American market with the assistance of his younger engineer brother Lewis Crosley. It had an fan-cooled twin cylinder engine of 638cc, producing 13.5bhp. This was located at the front of the cart sprung chassis.  Overall it was crude even by microcar standards and initially sold for $325.
Only 5757 examples were produced in the next four years, even though it was the last car to go out of production in the USA before war material production took over.  

A 1939 Croseley two seater

The Nineteen Forties
At the beginning of the nineteen forties all of Europe was at war or affected by war and there was very little opportunities for private motoring.  With the exceptions mentioned above , economy car production had ceased and and wouldn't resume until late in the decade. By the time some manufacturers in Europe were ready to resume car production its political and in some cases in national landscape had changed.

Aero Minor 11
Aero minor chassisJawa in Czechoslovakia had been working in secret throughout the German occupation on a new model, but with the advent of peace came a new communist government, state direction of industry dictated that that the new car would be called the Aero Minor and be produced in a Skoda plant. It had the 615 cc, twin cylinder two-stroke engine mounted longitudinally at the front of a backbone chassis driving the front wheels. Independent suspension front and rear, was by transverse leaf springs. In production from 1946 to 1952, over fourteen thousand were produced.

Aero Minor Chassis                                                                            Aero Minor 11

The DKW plant at Eisenach in Upper Saxony, Germany, was now in a new state the DDR, also a communist state and the factory was nationalised. Production of thr F8 was restarted in 1948 as the IFA and continued until 1955.

Drawing of the Saab 92
Saab 92
Sweden had managed to avoid getting involved in the fighting         Saab 92 Power TrainSaab92 engine

during the Second World War, but could not avoid the lack of new cars, as most cars had been imported before the war. The Swedish aircraft manufacturer Saab saw an opportunity to diversify by producing a small car. In the early nineteen forties they felt that with only one customer, the Swedish government they were very vulnerable. Their solution was to diversify, to manufacture cars. Before the Second World War Sweden only had one motor manufacturer Volvo and most cars were imported. Until the flow of imports stopped due to the war, DKW cars were becoming increasingly popular in Sweden, so SAAB decided to design and produce a car similar in principle to the DKW but incorporating the latest design thinking. The first car the "92", designed by two Swedish engineers Gunnar Ljungstrom designed the car while Sixten Sason designed the body. Having limited manufacturing capabilities Ljungstrom opted for a twin-cylinder two-stroke engine, located in front of the front wheels, transversely with the gearbox in line and the final drive behind, using the minimum space inside the wheelbase, which could then be utilized for passenger space. (This was the layout used in the Trabant, produced by IFA in the DDR for thirty plus years). The car had a low drag unitary chassis/body, rack and pinion steering and all independent suspension with torsion bar springs. Just over twenty thousand SAAB 92’s were produced in six years when discontinued in 1956 after the introduction of the SAAB 93 in 1955. This had a similar layout to the DKW F9, also with a three cylinder two-stroke engine.

A Panhard Dyna
Panhard DynaThe "Dyna" was the Panhard version of the Gregiore designed "Aluminum Francais-Gregiore" mentioned previously. J.A. Gregiore sold drawings of the A.F.G. to Henry J. Kaiser in the United States, and to Hartnett in Australia, but neither took it any further and submitted prototypes to Simca and Panhard in France. The Dyna Panhard, was based on the A.F.C, but Panhard made many changes to the design while retaining the principle features of the Gregiore design. First produced in 1946, with a 610cc engine that produced 25bhp, weighed 1052lb and could reach 60mph. n 1950 the engine size was increased to 750cc producing 33bhp and a top speed has risen to 71mph despite a weight increase of 220lb. By 1954 an 850cc engine was standardized on all models.
Also that year the original Gregiore devised chassis that had been made for Panhard by Facel Mettalon. It was replaced in a new model, the Dyna 54, but it was still constructed of aluminum, as was the body. The Dyna 54 was a six-seat car and could reach 80 mph, on 42bhp. In 1957 the aluminum construction was replaced by steel with an increase in weight of 440lb.The Dyna 54 was replaced by the PL17 in 1959, the most prolific model, with one hundred and thirty thousand examples produced by 1964.
The last of the breed the 24CT, which was the last Panhard car produced was a 2+2 coupe made from 1963 until 1967. Citroen had taken over the company in 1957 and from 1967 Panhard only produced armoured cars. Despite it's advanced layout the Dyna had not been properly developed and was expensive to produce never reaching mass popularity.

A Citreon 2CV
Citreon 2CVCitroen had started work on the 2CV in 1938 and had  300 prototypes running in France. That car was not put into full scale production due to the advent of war. The war years were spent totally revising the design. It took until 1948 before the car was first shown to the public at the Paris Show. Citroens aim was to provide rural France with a car that would replace the horse and trap, as Henry Ford had done for America with his model T thirty years before. To carry up to four people at speeds up to 40MPH along French country roads in a car that needed a minimum of maintenance at minimum cost, required an exceptional design and the 2CV was that. Every part of it was new from the power train to the basic almost crude body. Initially the air-cooled flat twin engine was of only 375cc producing 9bhp.  
                                                                                 Drawing of the 2CV Power Train2cv engine
It was at the front of a platform chassis, with the drive going to the front wheels with at first, simple universal joints at both ends of the drive shafts. This didn't matter at first due to the low performance and the need to keep the cost down. The drawings also show the unique suspension devised to deal with those country roads. Long travel leading arms at the front, were linked to long travel trailing arm at the rear by rods that operated on coil springs located at the side of the chassis. Suspension movement at the front was transmitted to the spring and then to the rear by the linkage, leading to a smother ride. To make the car as usable for it's designed purpose, the body was very simple with most components removable to provide access and space as required.    The 2CV at first glance could be taken for a crude car but looks are deceiving and where it mattered everything was produced to a high standard, with hydraulic brakes, inboard at the front and rack and pinion steering. The engine was increased to 424cc in 1954 and later 602cc, but performance wasn't what the 2CV had been designed for, it was as a work horse. Total production was 3,872,583 of 2CV's alone by 1990, not counting the models derived from it.

The Nineteen fifties
The nineteen fifties was the beginning of the boom time of the twin cylinder engine car, with at least twenty different models in production at some during the decade.

DKW F89The pre-war management of Auto Union set up in business in Ingolstadt, West Germany after the war, at first making spare parts for the remaining DKW cars produced before the war. But by 1950, began producing new a DKW car in the form of the F-89 New Meisterklasse. It was made in Düsseldorf also in West German. Based on the pre-war F-8 but with the 684cc engine moved ahead of the front wheels in a new chassis and clothed by the body designed for the F9. This was in production from 1950, by 1954 when production of the F89 ceased 59,475 had been made.

Drawing of a DKW F89

Goliath GT700

 Goliath-Werke Borgward began producing the Goliath GT700 in 1950. It had a 688cc
water-cooled, two-stroke, inline twin cylinder engine, mounted transversely as the DKW f-89. It was located at the front  with the drive to the front wheels.  About 1952 the fuel system was changed to Bosch fual injection. Thirty six thousand were produced.                                             From 1955 an 886cc version the GP900 was  produced, both twins were discontinued in1957. 

Gutbron Engine
Gutbrod Engine                                                                A Goliath GT700

 The small Gutbrod Superior model was produced from 1950 to 1954 using the company's own, front-mounted twin-cylinder two-stroke engines initially of 593cc. In April 1953 the engine size was increased to 663 cc for more expensive 'Luxus 700' versions of the car, while the standard model continued to be offered with the original smaller engine. Claimed power output was 20 hp (15 kW) for the base version, while for the larger engine 26 hp (19 kW) or 30 hp (22 kW) was claimed according to whether fuel feed came via a carburettor or a form of Bosch fuel injection. 7726 cars were produced before the factory was forced to close.

Lloyd lp600
Lloyd Motoren Werke GmbH of Bremen, Germany, began production of the Lloyd LP 300 in 1950, it had a twin cylinder two-stroke engine of 293cc. located at the front of a tubular backbone chassis, driving the front wheels, suspension front and rear was by twin transverse leaf springs and the steering was rack and pinion. The body was of wood and fabric. There were also LK estate and  LC coupe versions. 18087 were made before it was replaced by the LP400, with a 386cc engine In 1953 now with a steel body. A total of 109,878 examples of the LP,LK and LC versions of the 400 were produced between 1953 and 1957. In was joined by the LP,LK and LS 600 models in 1955 with a 596cc engine, and then in 1957  the 596cc Alexander model . The company became bankrupt in 1961 with 176524 of the larger engined models produced.

                                                                        A Lloyd LP600

Hans Glas GmbH, of Dingolfing, German, produced a range of miniature twins under the name of Goggomobile,from 1955 to1966, and after the factory was taken over by BMW production continued until 1969. They had an air-cooled, twin-cylinder, two-stroke, rear mounted engine driving the rear wheels via swing axle. The first model the T250 had a 245cc engine producing13.6hp. In1957 the T400 with a 392cc engine producing 18.5bhp, was added to the range. Over 280,000 saloon's and coupes were produced.

Drawing of a Goggomobile T250                                        Syrena102

The FSO Syrena 100/101/102/103 were manufactured by the Fabryka Samochodów Osobowych (FSO) in Warsaw,

from 1955-66. They had a twin-cylinder, water-cooled, two-stroke engine of 746cc, mounted longitudinally at the
 front driving the front wheels. 177,234 were made by FSO and  during its remarkably long production run it underwent only minor modifications.

                                                                                                                                               An FSO Syrena 102


The AWZ P70 "Zwickau" was a car made in East Germany by VEB Automobilwerke Zwickau (AWZ) between 1955 and 1958. After 1958 AWZ was united with the former Horch factory to the VEB Sachsenring Automobilwerke Zwickau and called Sachsenring P70.It succeeded the IFA F8 using the same 684 cc two cylinder, two-stroke engine but with a completely new glass fibre body. An estate version was introduced in 1956 followed by a coupé in 1957. It was replaced by the Trabant P50 in 1959 after about 36,000 had been made. The total output of AWZ P70 was 36,151 cars.


Suzuki Suzulight

Kei car, or keijidōsha ( "light automobile"), is a Japanese category of small vehicles, first introduced in 1949. It wasn't until 1955 when all classes of engine up to 360cc could be utilized that practical small cars were produced. The first was the 1955 Suzuki Suzulight SF series of cars that closely followed the specification of the Lloyd 400. They had a 360cc two-stroke, air-cooled twin-cylinder engine, but very few of this early model were produced. Full production only starting in 1962, continuing until 1967.

                                                                                                                                                                                      A Suzulight SF

Berkely SportsThere hadn't a British twin cylinder car since 1939, after the war when Jowett only produced a light van  twin, they  stopped that in 1952.
The next British twin was miniature sports car, produced by the Berkeley Caravan Company from 1956, the Berkeley Sports SA322. Berkeley had a wide experience producing GRP caravan bodies and used their expertise to produce a GRP chassis body assembly. Power was provided by a British Anzani twin-cylinder 322 cc two-stroke engine producing 15 bhp (11 kW; 15 PS)
and mounted transversely driving the front wheels via a chain and three speed gearbox.  One hundred and sixty three examples were produced by 1967 when the similar Excelsior engined SE328 replaced it. This was produced until 1958 with 1259 examples made. The las t of the Berkeley twins was the B95 and B105 models. These were fitted with twin-cylinder Royal Enfield 692 cc four-stroke engines, with the 40 bhp (30 kW; 41 PS) Super Meteor engine in the B95 and the 50 bhp (37 kW; 51 PS) Constellation unit in the B105. About two hundred of these were produced between 1959 and 1960, before Berkeley failed due to a falling caravan market. 

Berkeley Sports

Fiat Nuovo 500Fiat Nuovo 500
At Fiat Danti Giacosa's only design with a two-cylinder air-cooled engine was the Nuova 500 of 1957. Being a two/plus/two-seat car, it was the true
Steyr 500 replacement for the "Topolino", at the bottom of the Fiat range that had had a four cylinder engine. With a wheelbase fractionally over six feet and a length under nine feet, it was also a lightweight weighing less than five hundred kilos. The 479cc engines in the early production cars was so under powered with only 13 BHP that they  recalled and an up rated engine that produced 16.5 BHP was fitted. The final 500F of 1965 had a 499cc engine producing 18 BHP, sufficient to get to 70 MPH and a fuel consumption of 55 MPG. In production until 1975 with almost three pound nine million made.
 A version of the Nuova 500 was made by Styr-Puch in Austria in 1957, with their own flat-twin air-cooled engine and swing axle drive and suspension. The Styr 650TR of 1965 to 1969, was the hottest 500 model made and a competent rally car.                                                           Styr-Puch 500

BMW 600BMW had been making the Isetta micro car since 1955. In 1957 they introduced a compact four-seat, four wheeled mini car based on the Isetta. A 582cc version of their well known air-cooled flat twin engine that was located at the rear of the car. The BMW 600 shared with the Isetta the distinction of having a door at the very front of the car.  Almost thirty five thousand BMW 600's were produced by the time it was superseded by the BMW 700 in 1959. The 700 was a development of the design of the 600. The engine size was increased to 697cc, but the biggest change was theBMW 700 fitting of a new body designed by Michelotti. Production continued until 1965 and a total of 188,121 examples of all type were produced. An unusual feature of these cars, was the Dubonnet independent front suspension system used on the cars, probably the last time it was used in any design thousand 600's were made.
BMW 600                                                                             BMW 700

Vespa 400

The Vespa 400 was the Italian Piaggio companies only mini car. It was a two seat car with 393 cc two-stroke air-cooled twin cylinder engine giving it a maximum speed of 55 MPH. Thirty four thousand were made in the Piaggio factory in France from 1957 until 1961,

Vespa 400


The next model from VEB Sachsenring Automobilwerke, the Trebant P50, was in 1957 and it would stay in production until 1989 in almost original form with over three million produced. An 595cc air-cooled version of their two-stroke twin cylinder engine driving the front wheels was mounted in a type of steel unitary chassis frame. This was clothed in plastic body panels in a similar manner to the present day Smart cars. The panels were produced from waste products from other industries, cotton waste from the cotton industry and Phenol from the dye industry. Front and rear suspension was by transverse leaf springs and wishbones and steering by rack and pinion. Only minor changes were made for the later P600 and P601 models until the twin-cylinder engine was replaced in 1989.

                                                                                                                         A 1967 Trebant P601

NSU Sports

The first NSU designed car to go into production since 1928 the Prinz was a mini car with a 583cc transverse inline air-cooled twin cylinder engine producing 20BHP. An unusual feature of the engine was the Ultramax eccentric strap drive for the overhead camshaft. The unitary construction chassis was independently sprung with wishbones at the front and swing axles at the rear all with coil springs. The Prinz was produced from 1958 until 1973 and almost six hundred thousand were made. A pretty little coupe version the Sports Prinz was produced from 1959 to 1967. The engine was tuned to produce 30BHP and it had a top speed of 76MPH.             

Sports Prinz

Subaru 360The first car bearing the name Subaru the 360, was introduced in 1958. It had a twin cylinder two-stroke engine 0f 360cc located at the rear. Only six hundred and four were produced that year, but the rate of production had reached over twenty two thousand in 1961. This model later with a larger engine was in production for fourteen years.

                                                                                                                                            Subaru 360

In 1958 Glas, the makers of the Goggomobile introduced a totally different cars, in two forms the T600 andGlas Isar T700, both with  water-cooled horizontally opposed four stroke twin cylinder engines of 584cc and 688cc respectively. The transmission was also different to previous Goggomobiles in being like the old classic layout of front engine and rear wheel drive using a live axle. In 1959 the Goggomobile name was dropped and Glas Isar was substituted. Over ninety thousand examples of saloon and estate versions were produced before production ceased in 1965.

  A Glas Isar

There was an interesting newcomer to the to the light car world from Holland in1959, in the form of the DAF600. Its air cooled flat twin engine mounted at the front was not unusual for the time, but the drive toDAF 600 the rear wheels was. It consisted of a variable ratio belt drive controlled by the depression in the engines inlet manifold, this ensured an optimum engine performance. Starting in 1961 the DAF went through various models with the twin cylinder engine, rising from an initial 600 cc to 750 cc in the 33 to 844 cc in the 44.  From 1967 until 1972 a version with a Renault four cylinder engine of 1108 cc the 55 was also produced . Well over half a million of these unique cars were produced by 1973 when the type was discontinued. The later models where badged as Volvo’s.
                                                                                                                                                 DAF 600

The Nineteen Sixties

In 1960 Fiat introduced the "Gardinera", a 499cc station wagon with a similar inline twin cylinder engine as the Nuova500, but with cylinder horizontal. The engine was located under the Autobiancifloor at the rear of the car. With a slight increase in wheelbase and the weight increased to five hundred and seventy kilos, it was a four seat car with a luggage area over the engine. It remained in production until 1977 when 327,000 had been produced.

Also in 1960, a  Fiat subsidary Autobianchi, utilised the  Nuova500, platforms  to produce the the Bianchina range of models consisting of a convertible, a four seat saloon, an estate car and a van version the last two on the Gardinera platform, at their Desio factory. Over a quarter of a million of all types were produced by 1970 when production ceased. 

Autobianchi Bianchina Estate
Mazda R360

The Mazda R360 first produced in 1960 was their first car. It was in the Kei car category, with a rear mounted 360cc Vee twin engine driving the rear wheels and was in production until 1966.

Mitsubishi 500The Mitsubishi 500 type A10, in production from1960 to 1962, was Mitsubishi"s first car since 1921. It was a small two door  saloon with a 493cc, air-cooled, inline twin-cylinder four stroke engine located at the rear. With independent suspension all round and a maximum speed of 56 mph. This was replaced by the Colt 600. with a 594cc engine otherwise the same specification, which was in production from 1962 to 1965.
1969 Minica

Also in 1962 Mitsubishi introduced the Minica 360. which had an air-cooled two-stroke twin-cylinder engine of 359cc, located at the front, driving a live rear axle. Two-stroke Minica's were produced until 1972.

Mitsubishi 500                                                                  1969 Minica   

Citreon Ami 6
In 1961 Citroen introduced the Ami 6. The 2 CV platform was fitted with a 602 cc 22 bhp engine and a odd four door body. It was produced until 1971 and over a million examples were produced. A revised version the AMI 8 was introduced in 1969 and produced until 1978.

Citroen Ami 6

Toyota Publica
Toyota made the first of the Publica model in 1961 for the Japanese market. With a twin cylinder, horizontally opposed, air cooled  engine of 697 cc, producing 28 bhp, in a front engine/rear wheel drive chassis. An updated model with a 790cc engine was produced in 1966.  This in turn was superseded by the Toyota 1000, which had a basic version with the twin cylinder engine installed. 
Another Toyota twin was the Sports 800 of 1965. It was fitted with a 790cc engine producing 45 bhp.  Over three thousand were made by 1969.
                                                                                                                                   Toyota publica

Honda N600

Honda introduced their first front wheel drive car in 1966 the N360. It was fitted with a transversely mounted air cooled O.H.C four stroke parallel twin cylinder engine. Honda had extensive experience of this type of engine in their motorcycles. Other versions were the N400, N500, and N600, 1967 to 1973, that had engine sizes to match the name. Over 1.1 million examples had been produced by 1971 when the "N" series cars were replaced.

Honda N600


Daihatsu began production of a model in the Kia car category in 1966 the Fellow. With a water-cooled two-stroke twin-cylinder engine of 356cc producing 23hp. It had a front engine, rear wheel drive layout. It was in production until 1970.

                                                                                                                                  Daihatsu Fellow

Citroen Dyane

Citroen produced a more civilised, stylish version of the 2 CV in the Dyane. 1.44 million examples were produced between 1967 and 1984. At first with a 435 cc engine , later with of 602 cc engine first used in the Ami 6.

Citroen Diane

Subaru R2

Subaru replaced the 360 with the R2 in 1969, still with a air-cooled two-stroke engine of 356cc. This was replaced with a water-cooled version in 1971 and production ceased in 1972.

The Nineteen Seventies
Daihatsu Fellow Max Daihatsu's replacement for the Fellow, was the Fellow Max. First produced in
 1970, it had a 360cc two-stroke twin-cylinder engine, located at the front and driving the fronf wheels. To take advantage in changing regulations, a 547cc  single overhead camshaft for-stroke engine  substituted for the two-stroke engine in 1976.  This wa carried over to a new body shell in 1977, the name be changed to the Max Cuore. Production ceased in 1980.
Daihatsu Fellow Max

In 1970 Honda began producing the Z range of two seat miniature coupe's based on the N range mechanicals, from theHonda Z Z360 Kei cars to the Z600 which was for sale in markets other than Japan. Production ceased in 1972 with over forty thousand made.

Subaru Rex
                                                                                                Honda Z                                        

The Subaru Rex replaced the R2 in 1972 and was in production until 1992. During that time the rear mounted 258cc two-stoke engine was replaced with a four-stroke until that was later increased to 490cc then finally to 540cc.

A Subaru Rex

Fiat 126

Fiat produced a replacement for 500 in 1972  the Fiat126,  which was a revamped 500 with a new body shell. It was initially produced in Italy, with production in Poland by FSM as the 126p beginning in 1973.  The engine capacity in a later model the
Polish built hatchback 126bis introduced in 1986, was increased to 704cc, with a new water-cooled unit. Over four and a half million were produced before production ceased in 2000.
The 126 was also made by Zastava In Yugoslavia.

Minica F4GL
A Mitsubishi Minica with a single overhead camshaft, four-stroke engine the F4, was introduced in 1972 and was in production until 1989. As with the Subaru, the engine capacity was increased as regulation's allowed.


 Mitsubishi Minica F4

Citreon Visa SpecialCitroen LN
Citroen LN
In 1976 Citroen introduced the LN, which utilized a shortened Peugeot 104 platform with a 602cc Citroen air-cooled twin-cylinder engine. It was later increased to 652cc.
In 1978 Citroen introduced another new model based on the full sized  Peugeot 104, platform the Visa. One version of the Visa the Special, was fitted with a 652 cc version of the venerable air-cooled flat twin at that time was still in use in the LN and 2 CV. The Visa Special was in production until 1987.The LN was produced until 1986, alongside the Ami 6 until 1976, the Diane until 1984 and the Visa from 1978, also the 2CV that out lived them all.
Citroen Visa Special 


The Nineteen Eighties

Fiat PandaIn 1980 Fiat introduced the Panda. One version, the Panda 30, was fitted with 652cc twin-cylinder air-cooled engine as fitted in the Fiat 126, of the time, but located at the front driving the front wheels.

1980 Daihatsu MiraA Fiat Panda

The Daihatsu Mira L55 series was first produced in1980, replacing the  Max Cuore.  Again with the 547cc engine. A larger 617cc engined version the L60 Cuore  was produced along side the L55 from 1982. Both were produced until 1985.
                                                                                           Daihatsu Mira L55

Oltcit ClubBefore the merger with Peugeot in 1976, Citroen had developed a replacement design for the Ami and Diane models. This was not persuade as Peugeot designs were utilized. In the nineteen eighties Citroen began a joint venture with the Romanian Government to produce a small car and shelved Citroen design was the basis of the new car. Named the Oltcit, it was produced in two engine configurations, The Club had the air-cooled four from the GS and the Special was fitted with a 652cc version of the classic air-cooled twin. The Oltcet was produced from 1984 until 1995, with under various names in the later years. It seems that the Romanian Government could not pay Citroen any income from the deal, but they were allowed to have completed cars to sell. These they badged as The Citroen Axel. The twin-cylinder Axel the Club, was only sold in Romania, from 1984 to 1990.


The Nineteen Nineties
Cinquecento 700

In 1991 Fiat replaced the 126 with the front wheel drive Cinquecento, again produced by FSM in Poland. There where two basic engine options, a transverse four and a fore and aft mounted 704cc water-cooled twin developed from the 126bis unit. The later was produced only for the Polish market. The Cinquecento was in production until 1998.

                                                                                                                                         Fiat Cinquecento 704

The Twenty First Century

AixamAt the beginning of the twenty first century there were no new twin cylinder engined cars  for sale, except what is classified as a quadricycle in Europe, such as the Aixam and Microcar, with a specification and performance similar to the early Kia cars and nineteen sixties European minicars of the period, with performance limitations that exclude them from all but urban motoring they cannot be considered mainstream for today. Never the less, they are miniature cars in every other respect.

Tata NanoAixam
                                                                                                                Tata Nano
The Tata Nano, that was first produced in 2008, has to be viewed in the same manner. It also has a modest performance that if it was on sale in Britain, it would be confined to the slow lane on the motorway with the heavy trucks. The 624cc rear mounted engine producing 38ps, is comparable to those fitted in many millions of small cars of the past but more is expected from even the smallest car in the twenty first century.

Fiat 500
In 2010 Fiat added an engine option for its latest 500 model that at first glance seemed to harking back to the first 500, it being a twin-cylinder unit. But there the similarity to any previous Fiat twin ended. At 875cc it was larger than any twin since the nineteen fifties Panhard. It had a novel form of valve gear first used in the Fiat MultiAir four, this combined with a turbocharger gave it a power output at 85ps, that compared well with current normally aspiring 1.3 litre fours, with only sixty percent of the fuel consumption and emissions.
In 2011 the TwinAir was an option in the Fiat Panda and in 2012 in the Fiat Punto and Alfa Romero Mito.

Fiat 500

This brings us up to date with the story of the twin-cylinder engine. I am sure there be more in the future.