Jowett Jupiter
Encyclopedia
The Jowett Jupiter was a British car made by Jowett Cars Ltd
of Idle
, near Bradford
from 1950 to 1954. Following the launch of the all new Jowett Javelin
and its successes in competition Jowett decided to use its power train in a sports car for export in the hope of increasing their inadequate steel allocation.
, formerly with Auto Union
, to come to England. He joined ERA
in Dunstable and, amongst other projected development and chassis work, designed and developed what became the Jupiter's tubular steel chassis. The suspension used soft torsion bars and anti-roll bars front and rear with independent suspension at the front. The engine was mounted very far forward ahead of the front axle line with the radiator low behind it over the gearbox. Adjustment of the anti-roll bars easily influenced oversteer and understeer to provide fine suspension tuning. On this torsionally stiff frame Reg Korner of Jowett put a steel framed aluminium drophead coupé body with a bench seat for three people. Eberhorst's chassis had been designed for a closed coupé and it proved to require strengthening. The anti-roll bars were abandoned. There was no external access to the boot (trunk) and the bonnet (hood) was rear hinged and opened complete with the wings. These cars were only for export, it was hoped coachbuilders would supply the local market.
An initial 75 chassis were supplied to external coachbuilders such as Stabilimenti Farina
, Ghia Suisse
, Abbott of Farnham
and others in Britain. The high cost of these, mostly handsome, bodies for what was only a 1500 c.c. car obliged Jowett to build their own complete cars. The Jowett factory made 731 Mk1 and 94 Mk1a cars. The Mk 1a came out in late 1952 with a little more power (63 bhp) and an opening lid to a boot of larger capacity.
raised from 7.2:1 to 8.0:1 developing 60 bhp at 4500 rpm giving the car a maximum speed of 85 mph (137 km/h) and a 0-50 mph time of 11.7 seconds. Two Zenith
carburettors were fitted. A four speed gearbox with column change was used.
in 1950 had a top speed of 86.1 mph (138.6 km/h) and could accelerate from 0-60 mph (96.6 km/h) in 18.0 seconds. A fuel consumption of 25.1 mpgimp was recorded. The test car cost £1086 including taxes. At this time a Jaguar XK120 cost £1263 including taxes when tested by the same magazine.
another example won its class at 13th overall, driven by Marcel Becquart and Gordon Wilkins. Three examples of the R1 were made - one survives.
Jowett
Jowett was a manufacturer of light cars and light commercial vehicles in Bradford, West Yorkshire, England from 1906 to 1954.-Early history:Jowett was founded in 1901 by brothers Benjamin and William Jowett with Arthur V Lamb. They started in the cycle business and went on to make V-twin engines...
of Idle
Idle, West Yorkshire
The village of Idle and its outskirts make up a mainly residential suburban area in the city of Bradford, West Yorkshire, in England. The area is loosely bordered by the areas of Eccleshill, Wrose, Thackley and Greengates, in the north east of the city....
, near Bradford
Bradford
Bradford lies at the heart of the City of Bradford, a metropolitan borough of West Yorkshire, in Northern England. It is situated in the foothills of the Pennines, west of Leeds, and northwest of Wakefield. Bradford became a municipal borough in 1847, and received its charter as a city in 1897...
from 1950 to 1954. Following the launch of the all new Jowett Javelin
Jowett Javelin
The Jowett Javelin is an award-winning British car that was produced from 1947 to 1953 by Jowett Cars Ltd of Idle, near Bradford. The model went through five variants labelled PA to PE, each having a standard and "de luxe" option. The car was designed by Gerald Palmer during World War II and was...
and its successes in competition Jowett decided to use its power train in a sports car for export in the hope of increasing their inadequate steel allocation.
Design features
Jowett through Lawrence Pomeroy of The Motor joined forces with ERA and they persuaded Professor Dr Ing Eberan-EberhorstEberan von Eberhorst
Professor Dr Robert Eberan von Eberhorst , was a noted Austrian engineer, who designed the Auto Union Type D Grand Prix racing car.-Life:...
, formerly with Auto Union
Auto Union
Auto Union was an amalgamation of four German automobile manufacturers, founded in 1932 and established in 1936 in Chemnitz, Saxony, during the Great Depression. The company has evolved into present day Audi, as a subsidiary of Volkswagen Group....
, to come to England. He joined ERA
English Racing Automobiles
English Racing Automobiles was a British racing car manufacturer active from 1933 to 1954. Currently the ERA trademark is owned by a British kit-car manufacturer.-Prewar history:...
in Dunstable and, amongst other projected development and chassis work, designed and developed what became the Jupiter's tubular steel chassis. The suspension used soft torsion bars and anti-roll bars front and rear with independent suspension at the front. The engine was mounted very far forward ahead of the front axle line with the radiator low behind it over the gearbox. Adjustment of the anti-roll bars easily influenced oversteer and understeer to provide fine suspension tuning. On this torsionally stiff frame Reg Korner of Jowett put a steel framed aluminium drophead coupé body with a bench seat for three people. Eberhorst's chassis had been designed for a closed coupé and it proved to require strengthening. The anti-roll bars were abandoned. There was no external access to the boot (trunk) and the bonnet (hood) was rear hinged and opened complete with the wings. These cars were only for export, it was hoped coachbuilders would supply the local market.
An initial 75 chassis were supplied to external coachbuilders such as Stabilimenti Farina
Pininfarina
Pininfarina S.p.A. is an Italian car design firm and coachbuilder in Cambiano, Italy.Founded as Società anonima Carrozzeria Pinin Farina in 1930 by automobile designer and builder Battista "Pinin" Farina, Pininfarina has been employed by a wide variety of high-end automobile manufacturers,...
, Ghia Suisse
Ghia-Aigle
Carrosserie Ghia S.A., Aigle was a Swiss automobile design and manufacturing company, commonly referred to as Ghia-Aigle....
, Abbott of Farnham
E. D. Abbott Ltd
Abbott was a British coachbuilding company based in Farnham, Surrey.Edward Dixon Abbott had been employed in the design department of the Wolseley car company before joining the coachbuilders Page and Hunt which had started operations in 1920...
and others in Britain. The high cost of these, mostly handsome, bodies for what was only a 1500 c.c. car obliged Jowett to build their own complete cars. The Jowett factory made 731 Mk1 and 94 Mk1a cars. The Mk 1a came out in late 1952 with a little more power (63 bhp) and an opening lid to a boot of larger capacity.
Powertrain
The flat four overhead valve engine of 1486 cc was more highly tuned than in the Javelin and had its compression ratioCompression ratio
The 'compression ratio' of an internal-combustion engine or external combustion engine is a value that represents the ratio of the volume of its combustion chamber from its largest capacity to its smallest capacity...
raised from 7.2:1 to 8.0:1 developing 60 bhp at 4500 rpm giving the car a maximum speed of 85 mph (137 km/h) and a 0-50 mph time of 11.7 seconds. Two Zenith
Zenith Carburetters
Zenith Carburetters was a British company making carburettors. In 1955 they joined with their major pre-war rival Solex Carburettors and over time the Zenith brand name fell into disuse...
carburettors were fitted. A four speed gearbox with column change was used.
Rally success
The Jupiter was an instant success with a record-breaking class win at Le Mans in 1950, a class 1-2 in the 1951 Monte Carlo International Rally, the outright win of the 1951 Lisbon International Rally, and a class 1-2 at Dundrod in a gruelling 4-hr sports car race on public roads in September 1951 in Northern Ireland. This was a resurrection of the famous Ulster Tourist Trophy Race of 1928-1936 previously run on the 13.7 miles (22 km) Ards circuit. Le Mans was again class-won in 1951 and 1952, and lesser events were taken in 1952 but by 1953 newer faster cars were proving a match for the Jupiter which was after all a well-appointed touring car first and foremost.Performance
A car tested by the British magazine The MotorThe Motor (magazine)
The Motor was a British weekly car magazine founded on 28 January 1903....
in 1950 had a top speed of 86.1 mph (138.6 km/h) and could accelerate from 0-60 mph (96.6 km/h) in 18.0 seconds. A fuel consumption of 25.1 mpgimp was recorded. The test car cost £1086 including taxes. At this time a Jaguar XK120 cost £1263 including taxes when tested by the same magazine.
Jupiter R1
A racing derivative of the Jupiter, the R1, was entered in the 1951 1500 cc sports car race at Watkins Glen, driven to first place by George Weaver. In the 1952 24 Hours of Le Mans1952 24 Hours of Le Mans
The 1952 24 Hours of Le Mans was the 20th Grand Prix of Endurance, and took place on June 14 - 15 1952 at Circuit de la Sarthe.Less than a decade after World War II, Mercedes-Benz scored a 1-2 victory with their Mercedes-Benz 300SL which was equipped with a 3.0L I6 engine that had less power than...
another example won its class at 13th overall, driven by Marcel Becquart and Gordon Wilkins. Three examples of the R1 were made - one survives.
Jupiter R4
The original Jupiter was a somewhat heavy car and this handicapped its performance. An intended successor, the R4, was made with fibreglass body and a new lighter chassis and showed the potential of being a genuine 100 mph (161 km/h) car but Jowett closed before the car could reach production. Three prototypes were made of which two survive.External links
- Jowett Car Club Limited site
- Jowett Jupiter site
- Jowett North West Section
- North American Jowett Register
- Special Jupiters