The Return of the Twin

The Return of the Twin!
Fiat TwinAir Engine
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The 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 optimise 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
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Return of the Twin Cylinder Engine into Mainstream Motoring.!
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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.!
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The Return of the Twin!
Daimler Twin!
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Time line!
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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.!
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1890. A licensed version of this engine was used by Peugeot.!
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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.!
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1896. 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.!
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1896. 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 Page 2
The Return of the Twin!
Ford Quadricycle!
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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. !
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1897. 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. !
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1897. 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.!
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1899. Mors produced the "Petit Duc"' model with a 4 hp, twin cylinder horizontally opposed
engine with air-cooled cylinder barrels and water-cooled heads. !
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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.!
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1899. The Decauville Voiturelle, had a 479 cc, vertical twin mounted in the rear, it
produced 3 hp, at 1,200 rpm.!
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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 utilised.!
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1900. 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.!
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The Return of the Twin!
Arrel-Johnson!
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The earliest Renault models all voiterettes, 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.!
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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. !
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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.!
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The Return of the Twin!
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Albion Engine!
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Edwardian Era.!
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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.!
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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.!
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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 recognisable by its pear-shaped radiator.
The company made cars with single, two and four-cylinder engines.!
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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.!
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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, Page 5
The Return of the Twin!
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908 Humber 8!
and classed as a cycle car, although other than the engine it was conventional and in no
way crude.!
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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.!
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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.!
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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.!
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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.!
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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.!
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Others were the Alday Midget 8/10. Alday’s had also been making twins since 1906 but
would survive until the early 1920’s.!
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Chater-Lea were newcomer's with the Chater-Lea 8/9. With water-cooled and air-cooled
version’s available of the 8/9 engine..!
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The Return of the Twin!
GKW Chassis!
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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. The 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.!
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The 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.!
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The Return of the Twin!
Rover Eight!
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The Nineteen Twenties!
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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.!
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.!
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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 glamor to what was an unrefined noisy car.
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The Return of the Twin!
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Belsize-Bradshaw 9hp !
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1921. 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.!
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.!
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.
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The Return of the Twin!
Tatra T11 Engine Drawing!
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In 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 panelled 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.!
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In 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 fancooled 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. !
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DKW FA Power Unit!
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The Nineteen Thirties!
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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. !
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1931. 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. !
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.
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The Return of the Twin!
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Aero 662!
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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.!
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1933. In Czechoslovakia Tatra produced a rear engined prototype the V570, with an aircooled, OHV, horizontally opposed twin cylinder engine, but it was not put into production.!
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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 watercooled 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. !
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At 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.
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The Return of the Twin!
Hansa 500!
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Towards 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 396 cc 2-stroke
2-cylinder 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.!
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The 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 Reichklasse,
with a 589cc engine was made from 1939 to 1942 with 50,000 produced. !
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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. !
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1939 Crosley two seater!
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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.!
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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 Crosley. 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. !
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Aero Minor!
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The Nineteen Forties!
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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.!
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Jawa 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.!
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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 the F8 was
restarted in 1948 as the IFA and continued until 1955.!
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Sweden had managed to avoid getting involved in the fighting 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 Page 15
The Return of the Twin!
Drawing of the Saab 92!
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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 utilised 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. !
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The "Dyna" was the Panhard version of the Gregiore designed "Aluminum FrancaisGregiore" 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 1052 lb 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 standardised 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
aluminium, 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.!
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Citroen 2CV Power Unit!
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Citroen 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. !
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.!
!
!
Page 17
The Return of the Twin!
!
Lloyd 600!
!
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.!
!
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 fuel injection. Thirty six thousand were produced.
From 1955 an 886cc version the GP900 was produced, both twins were discontinued
in1957.!
!
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.
Page 18
The Return of the Twin!
!
FSO Syrena!
!
!
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.!
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.!
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, twostroke 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.!
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.
Page 19
The Return of the Twin!
!
Styr-Puch 500!
!
!
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
utilised 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.!
There 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. !
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 trueSteyr 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
Page 20
The Return of the Twin!
!
BMW 600!
!
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 flattwin 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.!
BMW 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.!
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.!
!
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.!
!
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The Return of the Twin!
1967 Trebant P601!
!
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. !
!
The 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. !
!
In 1958 Glas, the makers of the Goggomobile introduced a totally different cars, in two
forms the T600 and Glas 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.!
!
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.!
!
Page 22
The Return of the Twin!
!
!
Mazda R360 !
!
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 floor 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 subsidiary 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. !
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.!
The 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.!
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. !
!
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.!
!
Page 23
The Return of the Twin!
Honda N600!
!
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.!
!
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.!
!
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.!
!
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.!
!
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. !
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Page 24
The Return of the Twin!
Daihatsu Fellow Max!
!
The Nineteen Seventies!
!
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
front wheels. To take advantage in changing regulations, a 547cc single overhead
camshaft for-stroke engine substituted for the two-stroke engine in 1976. This was
carried over to a new body shell in 1977, the name be changed to the Max Cuore.
Production ceased in 1980.!
!
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.!
!
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.!
!
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.!
!
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.!
!
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Page 25
The Return of the Twin!
Fiat 126!
!
In 1976 Citroen introduced the LN, which utilised 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.!
!
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Page 26
The Return of the Twin!
!
1980 Daihatsu Mira !
!
The Nineteen Eighties!
!
In 1980 Fiat introduced the Panda. One version, the Panda 30, was fitted with 652cc twincylinder air-cooled engine as fitted in the Fiat 126, of the time, but located at the front
driving the front wheels.!
!
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.!
!
Before 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 utilised. 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.!
!
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Page 27
The Return of the Twin!
!
Fiat Cinquecento!
!
The Nineteen Nineties!
!
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.!
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Page 28
The Return of the Twin!
Fiat 500!
!
The Twenty First Century!
!
At 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.!
!
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.!
!
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.!
!
This brings us up to date with the story of the twin-cylinder engine. I am sure there be
more in the future.
Page 29