Grand Prix motor racing
Grand Prix motor racing has its roots in organised automobile racing that began in France as far back as 1894. It quickly evolved from a road race from one town to the next, to endurance tests for car. Grand Prix motor racing eventually evolved into formula racing, and Formula One can be seen as its direct descendant, each event of the Formula One World Championships is still called a Grand Prix, Formula One is referred to as Grand Prix racing. Motor racing was started in France, as a result of the enthusiasm with which the French public embraced the motor car. Manufacturers were enthusiastic due to the possibility of using motor racing as a window for their cars. The first motoring contest took place on July 22,1894 and was organised by a Paris newspaper, the Paris–Rouen rally was 126 km, from Porte Maillot in Paris, through the Bois de Boulogne, to Rouen. Count Jules-Albert de Dion was first into Rouen after 6 hours 48 minutes at an speed of 19 km/h. He finished 3 minutes 30 seconds ahead of Albert Lemaître, followed by Doriot, René Panhard, in 1900, James Gordon Bennett, Jr.
the owner of the New York Herald and the International Herald Tribune, established the Gordon Bennett Cup. He hoped the creation of an event would drive automobile manufacturers to improve their cars. Each country was allowed to enter up to three cars, which had to be built in the country that they represented and entered by that countrys automotive governing body. International racing colours were established in this event, in the United States, William Kissam Vanderbilt II launched the Vanderbilt Cup at Long Island, New York in 1904. Some anglophone sources wrongly list a race called the Pau Grand Prix in 1901 and this may stem from a mistranslation of the contemporary French sources such as the magazine La France Auto of March 1901. The name of the 1901 event was the Circuit du Sud-Ouest, the Grand Prix du Palais d’Hiver was the name of the prizes awarded for the lesser classes. The Grand Prix de Pau was the name of the awarded for the Heavy class. Thus Maurice Farman was awarded the Grand Prix de Pau for his victory in the Circuit du Sud-Ouest driving a Panhard 24 hp.
In L’Histoire de l’Automobile/Paris 1907 Pierre Souvestre described the 1901 event as, dans le Circuit du Sud-Ouest, à l’occasion du meeting de Pau. ” The only race at the time to carry the name Grand Prix was organised by the Automobile Club de France. The circuit used, which was based in Le Mans, was triangular in shape
Automobiles Ettore Bugatti was a French car manufacturer of high-performance automobiles, founded in 1909 in the German city of Molsheim, Alsace by Italian-born Ettore Bugatti. Bugatti cars were known for their beauty and for their many race victories. Famous Bugattis include the Type 35 Grand Prix cars, the Type 41 Royale, the Type 57 Atlantic and the Type 55 sports car. The death of Ettore Bugatti in 1947 proved to be the end for the marque, no more than about 8,000 cars were made. The company struggled financially, and released one last model in the 1950s, in the 1990s, an Italian entrepreneur revived it as a builder of limited production exclusive sports cars. Today, the name is owned by German automobile manufacturing group Volkswagen, the company was known both for the level of detail of its engineering in its automobiles, and for the artistic manner in which the designs were executed, given the artistic nature of Ettores family. During the war Ettore Bugatti was sent away, initially to Milan and to Paris and he exhibited three light cars, all of them closely based on their pre-war equivalents, and each fitted with the same overhead camshaft 4-cylinder 1, 368cc engine with four valves per cylinder.
Smallest of the three was a Type 13 with a body and using a chassis with a 2,000 mm wheelbase. The others were a Type 22 and a Type 23 with wheelbases of 2,250 and 2,400 mm respectively, the company enjoyed great success in early Grand Prix motor racing, in 1929 a privately entered Bugatti won the first ever Monaco Grand Prix. Racing success culminated with driver Jean-Pierre Wimille winning the 24 hours of Le Mans twice, Bugatti cars were extremely successful in racing. The little Bugatti Type 10 swept the top four positions at its first race, the 1924 Bugatti Type 35 is probably the most successful racing car of all time, with over 2,000 wins. The Type 35 was developed by Bugatti with master engineer and racing driver Jean Chassagne who drove it in the car’s first ever Grand Prix in 1924 Lyon, Bugattis swept to victory in the Targa Florio for five years straight from 1925 through 1929. Louis Chiron held the most podiums in Bugatti cars, and the modern marque revival Bugatti Automobiles S. A. S.
named the 1999 Bugatti 18/3 Chiron concept car in his honour. But it was the racing success at Le Mans that is most remembered—Jean-Pierre Wimille and Pierre Veyron won the 1939 race with just one car. In the 1930s, Ettore Bugatti got involved in the creation of a racer airplane and this would be the Bugatti 100P, which never flew. It was designed by Belgian engineer Louis de Monge who had already applied Bugatti Brescia engines in his Type 7.5 lifting body, Ettore Bugatti designed a successful motorised railcar, the Autorail Bugatti. The death of Ettore Bugattis son, Jean Bugatti, on 11 August 1939 marked a point in the companys fortunes. Jean died while testing a Type 57 tank-bodied race car near the Molsheim factory, World War II left the Molsheim factory in ruins and the company lost control of the property
A leaf spring is a simple form of spring commonly used for the suspension in wheeled vehicles. Originally called a laminated or carriage spring, and sometimes referred to as a spring or cart spring. A leaf spring takes the form of a slender arc-shaped length of spring steel of rectangular cross-section, in the most common configuration, the center of the arc provides location for the axle, while tie holes are provided at either end for attaching to the vehicle body. For very heavy vehicles, a spring can be made from several leaves stacked on top of each other in several layers. Leaf springs can serve locating and to some extent damping as well as springing functions, while the interleaf friction provides a damping action, it is not well controlled and results in stiction in the motion of the suspension. For this reason some manufacturers have used mono-leaf springs, a leaf spring can either be attached directly to the frame at both ends or attached directly at one end, usually the front, with the other end attached through a shackle, a short swinging arm.
The shackle takes up the tendency of the spring to elongate when compressed. Some springs terminated in an end, called a spoon end. There were a variety of springs, usually employing the word elliptical. Elliptical or full elliptical leaf springs referred to two circular arcs linked at their tips and this was joined to the frame at the top center of the upper arc, the bottom center was joined to the live suspension components, such as a solid front axle. Additional suspension components, such as trailing arms, would usually be needed for this design and that employed the lower arc, hence its name. As an example of leaf springs, the Ford Model T had multiple leaf springs over its differential that were curved in the shape of a yoke. As a substitute for dampers, some manufacturers laid non-metallic sheets in between the leaves, such as wood. Today leaf springs are used in heavy commercial vehicles such as vans and trucks, SUVs. For heavy vehicles, they have the advantage of spreading the load more widely over the vehicles chassis, whereas coil springs transfer it to a single point.
Unlike coil springs, leaf springs locate the axle, eliminating the need for trailing arms. A further advantage of a leaf spring over a spring is that the end of the leaf spring may be guided along a definite path. A more modern implementation is the leaf spring
A transmission is a machine in a power transmission system, which provides controlled application of the power. Often the term refers simply to the gearbox that uses gears and gear trains to provide speed. In British English, the term refers to the whole drivetrain, including clutch, prop shaft, differential. In American English, the term more specifically to the gearbox alone. The most common use is in vehicles, where the transmission adapts the output of the internal combustion engine to the drive wheels. Such engines need to operate at a high rotational speed, which is inappropriate for starting, stopping. The transmission reduces the engine speed to the slower wheel speed. Transmissions are used on bicycles, fixed machines. Often, a transmission has multiple gear ratios with the ability to switch between them as speed varies and this switching may be done manually or automatically. Directional control may be provided, single-ratio transmissions exist, which simply change the speed and torque of motor output.
The output of the transmission is transmitted via the driveshaft to one or more differentials, while a differential may provide gear reduction, its primary purpose is to permit the wheels at either end of an axle to rotate at different speeds as it changes the direction of rotation. Conventional gear/belt transmissions are not the mechanism for speed/torque adaptation. Alternative mechanisms include torque converters and power transformation, automatic transmissions use a valve body to shift gears using fluid pressures in conjunction with an ecm. Early transmissions included the right-angle drives and other gearing in windmills, horse-powered devices, and steam engines, in support of pumping, most modern gearboxes are used to increase torque while reducing the speed of a prime mover output shaft. This means that the shaft of a gearbox rotates at a slower rate than the input shaft. A gearbox can be set up to do the opposite and provide an increase in speed with a reduction of torque. Some of the simplest gearboxes merely change the rotational direction of power transmission.
Many typical automobile transmissions include the ability to select one of several gear ratios, in this case, most of the gear ratios are used to slow down the output speed of the engine and increase torque
France, officially the French Republic, is a country with territory in western Europe and several overseas regions and territories. The European, or metropolitan, area of France extends from the Mediterranean Sea to the English Channel and the North Sea, Overseas France include French Guiana on the South American continent and several island territories in the Atlantic and Indian oceans. France spans 643,801 square kilometres and had a population of almost 67 million people as of January 2017. It is a unitary republic with the capital in Paris. Other major urban centres include Marseille, Lille, Toulouse, during the Iron Age, what is now metropolitan France was inhabited by the Gauls, a Celtic people. The area was annexed in 51 BC by Rome, which held Gaul until 486, France emerged as a major European power in the Late Middle Ages, with its victory in the Hundred Years War strengthening state-building and political centralisation. During the Renaissance, French culture flourished and a colonial empire was established.
The 16th century was dominated by civil wars between Catholics and Protestants. France became Europes dominant cultural and military power under Louis XIV, in the 19th century Napoleon took power and established the First French Empire, whose subsequent Napoleonic Wars shaped the course of continental Europe. Following the collapse of the Empire, France endured a succession of governments culminating with the establishment of the French Third Republic in 1870. Following liberation in 1944, a Fourth Republic was established and dissolved in the course of the Algerian War, the Fifth Republic, led by Charles de Gaulle, was formed in 1958 and remains to this day. Algeria and nearly all the colonies became independent in the 1960s with minimal controversy and typically retained close economic. France has long been a centre of art, science. It hosts Europes fourth-largest number of cultural UNESCO World Heritage Sites and receives around 83 million foreign tourists annually, France is a developed country with the worlds sixth-largest economy by nominal GDP and ninth-largest by purchasing power parity.
In terms of household wealth, it ranks fourth in the world. France performs well in international rankings of education, health care, life expectancy, France remains a great power in the world, being one of the five permanent members of the United Nations Security Council with the power to veto and an official nuclear-weapon state. It is a member state of the European Union and the Eurozone. It is a member of the Group of 7, North Atlantic Treaty Organization, Organisation for Economic Co-operation and Development, the World Trade Organization, originally applied to the whole Frankish Empire, the name France comes from the Latin Francia, or country of the Franks
Mercedes-Benz is a global automobile manufacturer and a division of the German company Daimler AG. The brand is known for vehicles, coaches. The headquarters is in Stuttgart, Baden-Württemberg, the slogan for the brand is the best or nothing and Mercedes-Benz was one of the top growing brands in 2014 with 18% growth. The Mercedes automobile was first marketed in 1901 by Daimler-Motoren-Gesellschaft, emil Jellinek, an Austrian automobile entrepreneur who worked with DMG created the trademark in 1902, naming the 1901 Mercedes 35 hp after his daughter Mercedes Jellinek. The first Mercedes-Benz brand name vehicles were produced in 1926, following the merger of Karl Benzs, on 28 June 1926, Mercedes Benz was formed with the merger of Karl Benz and Gottlieb Daimlers two companies. Gottlieb Daimler was born on 17 March 1834 in Schorndorf, after training as a gunsmith and working in France, he attended the Polytechnic School in Stuttgart from 1857 to 1859. After completing various activities in France and England, he started work as a draftsman in Geislingen in 1862.
At the end of 1863, he was appointed inspector in a machine tool factory in Reutlingen. Throughout the 1930s, Mercedes-Benz produced the 770 model, a car that was popular during Germanys Nazi period, Adolf Hitler was known to have driven these cars during his time in power, with bulletproof windshields. Most of the models have been sold at auctions to private buyers. One of them is currently on display at the War Museum in Ottawa, the pontiffs Popemobile has often been sourced from Mercedes-Benz. In 1944,46,000 forced laborers were used in Daimler-Benzs factories to bolster Nazi war efforts, the company paid $12 million in reparations to the laborers families. Mercedes-Benz has introduced many technological and safety innovations that became common in other vehicles. Mercedes-Benz is one of the best-known and established automotive brands in the world, for information relating to the famous three-pointed star, see under the title Daimler-Motoren-Gesellschaft including the merger into Daimler-Benz.
As part of the Daimler AG company, the Mercedes-Benz Cars division includes Mercedes-Benz, mercedes-AMG became a majority owned division of Mercedes-Benz in 1999. The company was integrated into DaimlerChrysler in 1999, and became Mercedes-Benz AMG beginning on 1 January 1999, Daimlers ultra-luxury brand Maybach was under Mercedes-Benz cars division until 2013, when the production stopped due to poor sales volumes. It now exists under the Mercedes-Maybach name, with the models being ultra-luxury versions of Mercedes cars, Daimler coorporates with BYD Auto to make and sell a battery-electric car called Denza in China. In 2016, Daimler announced plans to sell Mercedes-Benz branded all-electric battery cars in China, beside its native Germany, Mercedes-Benz vehicles are manufactured or assembled in, Since its inception, Mercedes-Benz had maintained a reputation for its quality and durability
Steel is an alloy of iron and other elements, primarily carbon, that is widely used in construction and other applications because of its high tensile strength and low cost. Steels base metal is iron, which is able to take on two forms, body centered cubic and face centered cubic, depending on its temperature. It is the interaction of those allotropes with the elements, primarily carbon. In the body-centred cubic arrangement, there is an atom in the centre of each cube. Carbon, other elements, and inclusions within iron act as hardening agents that prevent the movement of dislocations that otherwise occur in the lattices of iron atoms. The carbon in steel alloys may contribute up to 2. 1% of its weight. Steels strength compared to pure iron is possible at the expense of irons ductility. With the invention of the Bessemer process in the mid-19th century and this was followed by Siemens-Martin process and Gilchrist-Thomas process that refined the quality of steel. With their introductions, mild steel replaced wrought iron, further refinements in the process, such as basic oxygen steelmaking, largely replaced earlier methods by further lowering the cost of production and increasing the quality of the product.
Today, steel is one of the most common materials in the world and it is a major component in buildings, tools, automobiles, machines and weapons. Modern steel is generally identified by various grades defined by assorted standards organizations, the noun steel originates from the Proto-Germanic adjective stakhlijan, which is related to stakhla. The carbon content of steel is between 0. 002% and 2. 1% by weight for plain iron–carbon alloys and these values vary depending on alloying elements such as manganese, nickel, tungsten, carbon and so on. Basically, steel is an alloy that does not undergo eutectic reaction. In contrast, cast iron does undergo eutectic reaction, too little carbon content leaves iron quite soft and weak. Carbon contents higher than those of steel make an alloy, commonly called pig iron, while iron alloyed with carbon is called carbon steel, alloy steel is steel to which other alloying elements have been intentionally added to modify the characteristics of steel. Common alloying elements include, nickel, molybdenum, titanium, tungsten and niobium.
Additional elements are important in steel, sulfur and traces of oxygen and copper. Alloys with a higher than 2. 1% carbon content, depending on other element content, cast iron is not malleable even when hot, but it can be formed by casting as it has a lower melting point than steel and good castability properties
Delage was a French luxury automobile and racecar company founded in 1905 by Louis Delage in Levallois-Perret near Paris, it was acquired by Delahaye in 1935 and ceased operation in 1953. The company was founded in 1905 by Louis Delage, who borrowed Fr 35,000 and its first location was on the Rue Cormeilles in Levallois-Perret. The company at first had just two lathes and three employees, one of them Peugeots former chief designer, Delage initially produced parts for Helbé, with the De Dion-Bouton engine and chassis assembled by Helbé, Delage added only the body. The first model was the Type A, a voiturette which appeared in 1906 and it was powered by a one-cylinder De Dion-Bouton of 4.5 or 9 hp. Like other early carmakers, Delage participated in racing, entering the Coupe de Voiturettes held at Rambouillet in November 1906 with a 9 hp racer. In 1907 the factory moved to the Rue Baudin Levallois, where a 4,000 m2 workshop allowed it to grow, the two-cylinder Delages were no match for the competition this year at the Coupe des Voiturettes.
In 1908, the success enabled the development of the factory and entry into more Grand Prix races and that year, racing success returned, Delage won the Grand Prix des Voiturettes held 6 July. This event, six laps of the 47.74 mi Dieppe Grand Prix circuit, saw 47 starters. Delage fielded three cars, a pair with 1,242 cc De Dion-Bouton twins, driven by Thomas and Lucas-Bonnard, Guyot won at an average 49.8 mph, not needing to stop for fuel. All three Delages finished this time, Thomas the quickest of the cars, while the team took home the regularity prize. These good results contributed to total sales exceeding 300 cars for the year, Delage converted to four-cylinder engines in 1909, at first provided by De Dion and Edouard Ballot, the company were producing their own sidevalve fours, too. After an increase in sales, the facilities were too small, so in 1910 the factory moved to a new facility at 138 Boulevard de Verdun. The following year saw the creation of advanced bodywork, by 1912,350 workers were producing over 1000 cars annually, and offered four- and six-cylinder sidevalve engines.
During the First World War, Delage produced munitions, production of passenger cars virtually stopped, with the exception of some fabrication for the Army. But the Delage factories were running full support for the war effort, when the war concluded, Delage moved away from small cars and made its reputation with larger cars. First up was the CO, with a 4,524 cc fixed-head sidevalve six producing 20 hp, the CO plans had been drawn up during the conflict, this was the first passenger car with front brakes. It was joined by the DO with a 3-liter four, the 1920s were really the first Golden Age of Delage. The most famous were the DE and DI,4 cylinders of about 2 liters and 11 hp, Delage attempted to compete with Hispano-Suiza, with the GL of 30 hp and 5954 cc, with some success
Bentley Motors Limited is a British manufacturer and marketer of luxury cars and SUVs—and a subsidiary of Volkswagen AG since 1998. The joining and eventual separation of Bentley and Rolls-Royce follows a series of mergers and acquisitions, beginning with the 1931 purchase by Rolls-Royce of Bentley, Rolls-Royce Motors was subsequently sold to engineering conglomerate, Vickers and in 1998, Vickers sold Rolls-Royce to Volkswagen AG. The aerospace company, Rolls-Royce Plc, ultimately sold both to BMW AG, at the DFP factory, in 1913, he noticed an aluminum paperweight and thought that aluminum might be a suitable replacement for cast iron to fabricate lighter pistons. The first Bentley aluminum pistons were fitted to Sopwith Camel aero engines during World War I, in August 1919, W. O. registered Bentley Motors Ltd. and in October he exhibited a car chassis, with dummy engine, at the London Motor Show. Ex–Royal Flying Corps officer Clive Gallop designed an innovative 4 valves per cylinder engine for the chassis, by December the engine was built and running.
Delivery of the first cars was scheduled for June 1920, the durability of the first Bentley cars earned widespread acclaim and they competed in hill climbs and raced at Brooklands. Bentleys first major event was the 1922 Indianapolis 500, a race dominated by specialized cars with Duesenberg racing chassis and they entered a modified road car driven by works driver, Douglas Hawkes, accompanied by riding mechanic, H. S. Bertie Browning. Hawkes completed the full 500 miles and finished 13th with an speed of 74.95 mph after starting in 19th position. The team was rushed back to England to compete in the 1922 RAC Tourist Trophy. In ironic reference to his heavyweight boxers stature, Captain Woolf Barnato was nicknamed Babe, in 1925, he acquired his first Bentley, a 3-litre. With this car he won numerous Brooklands races, just a year he acquired the Bentley business itself. The Bentley enterprise was always underfunded, but inspired by the 1924 Le Mans win by John Duff and Frank Clement, Barnato had incorporated Baromans Ltd in 1922, which existed as his finance and investment vehicle.
Via Baromans, Barnato initially invested in excess of £100,000, saving the business, a financial reorganisation of the original Bentley company was carried out and all existing creditors paid off for £75,000. Existing shares were devalued from £1 each to just 1 shilling, Barnato held 149,500 of the new shares giving him control of the company and he became chairman. Barnato injected further cash into the business, £35,000 secured by debenture in July 1927, £40,000 in 1928, with renewed financial input, W. O. Bentley was able to design another generation of cars. The Bentley Boys were a group of British motoring enthusiasts that included Woolf Barnato, Sir Henry Tim Birkin, steeple chaser George Duller, aviator Glen Kidston, sammy Davis, and Dr Dudley Benjafield. The Bentley Boys, favored Bentley cars, many were independently wealthy and often had a military background. They kept the reputation for high performance alive, Bentley was noted for its four consecutive victories at the 24 Hours of Le Mans from 1927 to 1930
Brooklands was a 2. 75-mile motor racing circuit and aerodrome built near Weybridge in Surrey, United Kingdom. It opened in 1907 and was the worlds first purpose-built motor racing circuit as well as one of Britains first airfields, the Brooklands motor circuit was the brainchild of Hugh F. Locke King, and was the first purpose-built banked motor race circuit in the world. Apparently drawing inspiration from the development at Brooklands, the Indianapolis Motor Speedway was built soon afterwards, requirements of speed and spectator visibility led to the Brooklands track being built as a 100 ft wide,2.75 miles long, banked oval. The banking was nearly 30 feet high in places, in addition to the oval, a bisecting Finishing Straight was built, increasing the track length to 3.25 miles, of which 1.25 miles was banked. It could host up to 287,000 spectators in its heyday, owing to the complications of laying tarmacadam on banking, and the expense of laying asphalt, the track was built in uncoated concrete.
This led in years to a bumpy ride, as the surface suffered differential settlement over time. Along the centre of the track ran a black line. By driving over the line, a driver could take the banked corners without having to use the steering wheel. The Brooklands Mountain Circuit was a section of the track giving a lap 1¼ miles long, running from the Fork to the rear of Members Hill. It was created in 1930 using movable barriers, on 28–29 June 1907, eleven days after the circuit opened, it played host to the worlds first 24-hour motor event, with Selwyn Edge leading three specially converted Napier cars around the circuit. A statement of intent had been made in 1906, and Selwyn Edge entered into a training program to prepare for the event. His car,804 was extensively modified, having a fuel tank, bodywork removed. Over 300 red railway lamps were used to light the track during the night, flares were used to mark the upper boundary of the track. Edge drove his car for the duration, with the drivers of the other two cars taking the more familiar shift approach.
During the event Edge covered a distance of 1,581.74 mi at an speed of 65.91 mph. Women were not allowed to compete for several years, edges leading driver, was refused entry despite having been the first English-woman to compete in a motor race in 1903, and holding the Ladies World Land Speed Record. Edge completed 2,545 km at an average 106.06 km/h, the first standard race meeting would be held the next week, on 6 July. George E. Stanley broke the record at Brooklands race track on a Singer motorcycle in 1912
A supercharger is an air compressor that increases the pressure or density of air supplied to an internal combustion engine. This gives each intake cycle of the more oxygen, letting it burn more fuel and do more work. Power for the supercharger can be provided mechanically by means of a belt, shaft, when power is provided by a turbine powered by exhaust gas, a supercharger is known as a turbosupercharger – typically referred to simply as a turbocharger or just turbo. Common usage restricts the term supercharger to mechanically driven units, in 1848 or 1849 G. Jones of Birmingham, England brought out a Roots-style compressor. The worlds first functional, actually tested engine supercharger was made by Dugald Clerk, gottlieb Daimler received a German patent for supercharging an internal combustion engine in 1885. Louis Renault patented a centrifugal supercharger in France in 1902, an early supercharged race car was built by Lee Chadwick of Pottstown, Pennsylvania in 1908 which reportedly reached a speed of 100 mph.
The worlds first series-produced cars with superchargers were Mercedes 6/25/40 hp, both models were introduced in 1921 and had Roots superchargers. They were distinguished as Kompressor models, the origin of the Mercedes-Benz badging which continues today, on March 24,1878 Heinrich Krigar of Germany obtained patent #4121, patenting the first ever screw-type compressor. Later that same year on August 16 he obtained patent #7116 after modifying and improving his original designs and his designs show a two-lobe rotor assembly with each rotor having the same shape as the other. Although the design resembled the Roots style compressor, the screws were clearly shown with 180 degrees of twist along their length, the technology of the time was not sufficient to produce such a unit, and Heinrich made no further progress with the screw compressor. Nearly half a century later, in 1935, Alf Lysholm and he patented the method for machining the compressor rotors. There are two types of superchargers defined according to the method of gas transfer, positive displacement.
Positive displacement blowers and compressors deliver an almost constant level of pressure increase at all engine speeds, dynamic compressors do not deliver pressure at low speeds, above a threshold speed, pressure increases with engine speed. Positive-displacement pumps deliver a nearly fixed volume of air per revolution at all speeds, Roots superchargers are external compression only. External compression refers to pumps that transfer air at ambient pressure into the engine, if the engine is running under boost conditions, the pressure in the intake manifold is higher than that coming from the supercharger. That causes a backflow from the engine into the supercharger until the two reach equilibrium and it is the backflow that actually compresses the incoming gas. This is an inefficient process and the factor in the lack of efficiency of Roots superchargers when used at high boost levels. The lower the boost level the smaller is this loss, and Roots blowers are very efficient at moving air at low pressure differentials, all the other types have some degree of internal compression
Hertfordshire is a county in southern England, bordered by Bedfordshire to the north, Cambridgeshire to the north-east, Essex to the east, Buckinghamshire to the west and Greater London to the south. For government statistical purposes, it is placed in the East of England region, in 2013, the county had a population of 1,140,700 living in an area of 634 square miles. Four towns have between 50,000 and 100,000 residents, Hemel Hempstead, Watford and St Albans. Hertford, once the market town for the medieval agricultural county derives its name from a hart. Elevations are high for the region in the north and west and these reach over 240m in the western projection around Tring which is in the Chilterns. The countys borders are approximately the watersheds of the Colne and Lea, hertfordshires undeveloped land is mainly agricultural and much is protected by green belt. The countys landmarks span many centuries, ranging from the Six Hills in the new town of Stevenage built by local inhabitants during the Roman period, Leavesden filmed much of the UK-based $7.7 Bn box office Harry Potter film series and has the countrys studio tour.
Saint Alban, a Romano-British soldier, took the place of a Christian priest and was beheaded on Holywell Hill and his martyrs cross of a yellow saltire on a blue background is reflected in the flag and coat of arms of Hertfordshire. Hertfordshire is well-served with motorways and railways, providing access to London. The largest sector of the economy of the county is in services, Hertfordshire was the area assigned to a fortress constructed at Hertford under the rule of Edward the Elder in 913. Hertford is derived from the Anglo-Saxon heort ford, meaning deer crossing, the name Hertfordshire is first recorded in the Anglo-Saxon Chronicle in 1011. Deer feature in many county emblems, there is evidence of humans living in Hertfordshire from the Mesolithic period. It was first farmed during the Neolithic period and permanent habitation appeared at the beginning of the Bronze Age and this was followed by tribes settling in the area during the Iron Age. 293 the first recorded British martyrdom is believed to have taken place.
Saint Alban, a Romano-British soldier, took the place of a Christian priest and was beheaded on Holywell Hill. His martyrs cross of a saltire on a blue background is reflected in the flag. He is the Patron Saint of Hertfordshire, with the departure of the Roman Legions in the early 5th century, the now unprotected territory was invaded and colonised by the Anglo-Saxons. By the 6th century the majority of the county was part of the East Saxon kingdom