Alloy wheels are wheels that are made from an alloy of aluminium or magnesium. Alloys are mixtures of a metal and other elements and they generally provide greater strength over pure metals, which are usually much softer and more ductile. Alloys of aluminium or magnesium are typically lighter for the strength, provide better heat conduction. Although steel, the most common used in wheel production, is an alloy of iron and carbon. The earliest light-alloy wheels were made of magnesium alloys, although they lost favor on common vehicles, they remained popular through the 1960s, albeit in very limited numbers. In the mid-to-late 1960s, aluminum-casting refinements allowed the manufacture of safer wheels that were not as brittle, until this time, most aluminum wheels suffered from low ductility, usually ranging from 2-3% elongation. Once these aluminum casting improvements were widely adopted, the aluminum wheel took the place of magnesium as low cost. Reduction in overall vehicle mass can help to fuel consumption.
Alloy wheels are purchased for cosmetic purposes although the cheaper alloys used are usually not corrosion-resistant, alloys allow the use of attractive bare-metal finishes, but these need to be sealed with paint or wheel covers. Even if so protected the wheels in use will start to corrode after 3 to 5 years. The manufacturing processes allow intricate, bold designs, in contrast, steel wheels are usually pressed from sheet metal, and welded together and must be painted to avoid corrosion and/or hidden with wheel covers/hub caps. Alloy wheels are prone to corrosion, which can cause the tires to leak air if appropriate preventive measures are not taken. Also, alloy wheels are more difficult to repair than steel wheels when bent, alloy wheels have long been included as standard equipment on higher-priced luxury or sports cars, with larger-sized or exclusive alloy wheels being options. The high cost of alloy wheels makes them attractive to thieves, to counter this, most alloy wheels are manufactured using casting, but some are forged.
Forged wheels are lighter, but much more expensive than cast wheels. There are two types of forged wheels, one piece and modular, Modular forged wheels may feature two- or three-piece design. Typical multi-piece wheels consist of the inner rim base, outer rim lip, all parts of a modular wheel are held with bolts. BBS RS is one of the most famous three-piece modular forged wheels, a sizable selection of alloy wheels are available to automobile owners who want lighter, more visually appealing, and/or larger wheels on their cars
Leather is a durable and flexible material created by tanning animal rawhide and skin, often cattle hide. It can be produced at manufacturing scales ranging from cottage industry to heavy industry, people use leather to make various goods—including clothing, leather wallpaper, and as a furniture covering. It is produced in a variety of types and styles. Several tanning processes transform hides and skins into leather, Chrome-tanned leather, invented in 1858, is tanned using chromium sulfate and it is more supple and pliable than vegetable-tanned leather and does not discolor or lose shape as drastically in water as vegetable-tanned. It is known as wet-blue for its color derived from the chromium, more exotic colors are possible when using chrome tanning. The chrome tanning method usually only takes a day to finish, and it is reported that chrome-tanned leather adds up to 80% of the global leather supply. Vegetable-tanned leather is tanned using tannins and other found in different vegetable matter, such as tree bark prepared in bark mills, leaves, fruits.
It is supple and brown in color, with the exact shade depending on the mix of chemicals and it is the only form of leather suitable for use in leather carving or stamping. Vegetable-tanned leather is not stable in water, it tends to discolor, so if left to soak and dried it shrinks, in hot water, it shrinks drastically and partly congeals—becoming rigid, and eventually brittle. Boiled leather is an example of this, where the leather has been hardened by being immersed in hot water, historically, it was occasionally used as armour after hardening, and it has been used for book binding. Aldehyde-tanned leather is tanned using glutaraldehyde or oxazolidine compounds and this is the leather that most tanners refer to as wet-white leather due to its pale cream or white color. It is the type of chrome-free leather, often seen in shoes for infants. Formaldehyde tanning is another aldehyde tanning method, brain-tanned leathers fall into this category, and are exceptionally water absorbent. Brain tanned leathers are made by a process that uses emulsified oils, often those of animal brains such as deer, cattle.
They are known for their softness and washability. Chamois leather falls into the category of aldehyde tanning, and like brain tanning, produces a porous, chamois leather is made using marine oils that oxidize easily to produce the aldehydes that tan the leather to color it. Rose-tanned leather is a variation of oil tanning and brain tanning. Rose-tanned leather tanned leaves a powerful rose fragrance even years from when it is manufactured and it has been called the most valuable leather on earth, but this is mostly due to the high cost of rose otto and its labor-intensive tanning process
Differential (mechanical device)
In automobiles and other wheeled vehicles, the differential allows the outer drive wheel to rotate faster than the inner drive wheel during a turn. This is necessary when the vehicle turns, making the wheel that is traveling around the outside of the turning curve roll farther and faster than the other, the average of the rotational speed of the two driving wheels equals the input rotational speed of the drive shaft. An increase in the speed of one wheel is balanced by a decrease in the speed of the other, when used in this way, a differential couples the input shaft to the pinion, which in turn runs on the ring gear of the differential. This works as reduction gearing, on rear wheel drive vehicles the differential may connect to half-shafts inside an axle housing, or drive shafts that connect to the rear driving wheels. Front wheel drive tend to have the pinion on the end of the main-shaft of the gearbox. There are individual drive-shafts to each wheel, non-automotive uses of differentials include performing analog arithmetic.
The ball was painted black and white in hemispheres, and graphically showed the phase of the moon at a point in time. See the Chinese South-pointing chariot, an equation clock that used a differential for addition was made in 1720. In the 20th Century, large assemblies of many differentials were used as analog computers, for example, the development of electronic digital computers has made these uses of differentials obsolete. Practically all the differentials that are now made are used in automobiles, there are many claims to the invention of the differential gear, but it is possible that it was known, at least in some places, in ancient times. Some historical milestones of the include,100 BC–70 BC. Some such chariots may have used differential gears,658,666 AD, two Chinese Buddhist monks and engineers create south-pointing chariots for Emperor Tenji of Japan. 1720, Joseph Williamson uses a gear in a clock. 1810, Rudolph Ackermann of Germany invents a four-wheel steering system for carriages,1827, modern automotive differential patented by watchmaker Onésiphore Pecqueur of the Conservatoire National des Arts et Métiers in France for use on a steam wagon.
1832, Richard Roberts of England patents gear of compensation, a differential for road locomotives,1874, Aveling and Porter of Rochester, Kent list a crane locomotive in their catalogue fitted with their patent differential gear on the rear axle. 1876, James Starley of Coventry invents chain-drive differential for use on bicycles,1897, first use of differential on an Australian steam car by David Shearer. 1958, Vernon Gleasman patents the Torsen dual-drive differential, a type of differential that relies solely on the action of gearing, instead of a combination of clutches. An epicyclic differential can use epicyclic gearing to split and apportion torque asymmetrically between the front and rear axles, an epicyclic differential is at the heart of the Toyota Prius automotive drive train, where it interconnects the engine, motor-generators, and the drive wheels
A grand tourer is a performance and luxury automobile capable of high speed and long-distance driving. The most common format is a two-door coupé with either a two-seat or a 2+2 arrangement, the grand touring concept is eurocentric, the definition implies material differences in performance at speed and amenities between elite automobiles and those of ordinary motorists. In post-war United States, the Interstate Highway System and wide availability of powerful Straight-six, European GTs did find success penetrating the American personal luxury car market, notably the Mercedes-Benz SL-Class. Grand touring car design evolved from vintage and pre-World War II fast touring cars, italy developed the first gran turismo cars. The small, light-weight and aerodynamic coupé, named the Berlinetta, independent carrozzeria provided light and flexible fabric coachwork for powerful short-wheelbase fast-touring chassis by manufacturers such as Alfa Romeo. Later, Carrozzeria Touring of Milan would pioneer sophisticated Superleggera aluminium bodywork, the additional comfort of an enclosed cabin was beneficial for the Mille Miglia road-race held in Italys often wintry north.
An improved and supercharged version, the 6C1750 GTC Gran Turismo Compressore, from the basic Fiat 508 Balilla touring chassis came the SIATA and Fiat aerodynamic gran turismo-style Berlinetta Mille Miglias of 1933 and 1935. The first recognised motor race for gran turismo cars was the 1949 Coppa Inter-Europa held at Monza, the Fiat based 1100 cc four-cylinder Cisitaila was no match on the race track for Ferraris new hand-built 2000 cc V12, and Ferrari dominated, taking the first three places. An 1100 cc class was created, but not in time to save Cisitalias business fortunes—the companys bankrupt owner Piero Dusio had already decamped to Argentina. The Maserati A61500 won the 1500 cc class at the 1949 Coppa-Europa and it was driven by Franco Bordoni, former fighter ace of the Regia Aeronautica who had debuted as a pilota da corsa at the 1949 Mille Miglia. The body of the A61500 was an elegant two-door fast-back coupe body, the first car constructed in Ferraris name, the V12125 S, a racing sports car, debuted in 1947 at the Piacenza racing circuit.
The Ferrari 166 Inter S coupé model won the 1949 Coppa Inter-Europa, regulations stipulated body form and dimensions but did not at this time specify a minimum production quantity. The car was driven by Bruno Sterzi, and is recognized as the first Ferrari gran turismo, Ferraris response for the new Gran Tursimo championship was the road/race Ferrari 212. All versions came with the standard Ferrari five-speed non-synchromesh gearbox and hydraulic drum brakes, all 1951 Ferraris shared a double tube frame chassis design evolved from the 166. Double-wishbone front suspension with leaf spring, and live rear axle with semi-elliptic leaf springs. Even more impressive than the new Ferrari in 1951 was the debut of Lancias Aurelia B20 GT. Lancia had begun production in 1950 of their technically advanced Aurelia sedan, at the 1951 Turin Motor Show, the Pinin Farina-bodied Gran Tursimo B20 Coupé version was unveiled to an enthusiastic motoring public. In the B20 are elements of the Cistalia of 1947, coupés which Pinin undertook on a 6C Alfa Romeo and Maserati in 1948, in addition the B20 had a shorter wheelbase and a higher rear axle ratio, making it a 100 mph car
An engine or motor is a machine designed to convert one form of energy into mechanical energy. Heat engines burn a fuel to heat, which is used to create a force. Electric motors convert electrical energy into motion, pneumatic motors use compressed air. In biological systems, molecular motors, like myosins in muscles, use energy to create forces. The word engine derives from Old French engin, from the Latin ingenium–the root of the word ingenious. Pre-industrial weapons of war, such as catapults and battering rams, were called siege engines, the word gin, as in cotton gin, is short for engine. Most mechanical devices invented during the revolution were described as engines—the steam engine being a notable example. However, the steam engines, such as those by Thomas Savery, were not mechanical engines. In this manner, an engine in its original form was merely a water pump. Devices converting heat energy into motion are commonly referred to simply as engines, examples of engines which exert a torque include the familiar automobile gasoline and diesel engines, as well as turboshafts.
Examples of engines which produce thrust include turbofans and rockets, the term motor derives from the Latin verb moto which means to set in motion, or maintain motion. Thus a motor is a device that imparts motion and engine came to be used largely interchangeably in casual discourse. However, the two words have different meanings, rocketry uses the term rocket motor, even though they consume fuel. A heat engine may serve as a prime mover—a component that transforms the flow or changes in pressure of a fluid into mechanical energy. An automobile powered by a combustion engine may make use of various motors and pumps. Another way of looking at it is that a motor receives power from an external source, simple machines, such as the club and oar, are prehistoric. More complex engines using human power, animal power, water power, wind power and these were used in cranes and aboard ships in Ancient Greece, as well as in mines, water pumps and siege engines in Ancient Rome. The writers of those times, including Vitruvius and Pliny the Elder, treat these engines as commonplace, by the 1st century AD, cattle and horses were used in mills, driving machines similar to those powered by humans in earlier times
Hidden headlamps first appeared on the Cord 810 in 1936. Each unit had a crank on its side of the dashboard, powered hidden headlamps were pioneered in GMs Buick Y-Job concept car of 1938 and were used briefly on Chrysler Corporations 1942 production DeSoto. The features popularity has waxed and waned over time, hidden headlamps regained popularity in the late 1960s, particularly in the US market where aerodynamic headlamps were not permitted. A relatively large variety of cars incorporated hidden headlamps in the 1970s, 1980s, hidden headlamps are out of favour. US laws now permit aerodynamic headlamps, relative to which hidden headlamps represent added cost, the last time pop-up headlamps appeared on a volume-production car was in 2004 when both the Lotus Esprit and C5 Corvette ended production
An anti-roll bar is a part of many automobile suspensions that helps reduce the body roll of a vehicle during fast cornering or over road irregularities. It connects opposite wheels together through short lever arms linked by a torsion spring, a sway bar increases the suspensions roll stiffness—its resistance to roll in turns, independent of its spring rate in the vertical direction. The first stabilizer bar patent was awarded to Canadian inventor Stephen Coleman of Fredericton, anti-roll bars were unusual on pre-war cars due to the generally much stiffer suspension and acceptance of body roll. From the 1950s, production cars were commonly fitted with anti-roll bars. With the bar removed, a vehicles wheels can tilt away by much larger distances. Although there are variations in design, a common function is to force the opposite wheels shock absorber, spring or suspension rod to lower, or rise. In a fast turn, a vehicle tends to drop closer onto the wheels. As a result, the vehicle tends to hug the road closer in a fast turn, where all wheels are closer to the body.
After the fast turn, the pressure is reduced. A vehicle that runs over several potholes scattered in the road tends to rock side-to-side, or waddle, a sway bar is usually a torsion spring that resists body roll motions. It is usually constructed out of a steel bar, formed into a U shape. If the left and right wheels move together, the bar rotates about its mounting points, if the wheels move relative to each other, the bar is subjected to torsion and forced to twist. Each end of the bar is connected to an end link through a flexible joint, the sway bar end link connects in turn to a spot near a wheel or axle, transferring forces from a heavily-loaded axle to the opposite side. The bar resists the torsion through its stiffness, the stiffness of an anti-roll bar is proportional to the stiffness of the material, the fourth power of its radius, and the inverse of the length of the lever arms. Stiffness is related to the geometry of the mounting points, the stiffer the bar, the more force required to move the left and right wheels relative to each other.
This increases the amount of required to make the body roll. In a turn the sprung mass of the body produces a lateral force at the centre of gravity. Because the CG is usually not on the axis, the lateral force creates a moment about the roll axis that tends to roll the body
Modena is a city and comune on the south side of the Po Valley, in the Province of Modena in the Emilia-Romagna region of northern Italy. One of Ferraris cars, the 360 Modena, was named after the town itself, the University of Modena, founded in 1175 and expanded by Francesco II dEste in 1686, has traditional strengths in economics and law and is the second oldest athenaeum in Italy. Italian military officers are trained at the Military Academy of Modena, the Biblioteca Estense houses historical volumes and 3,000 manuscripts. The Cathedral of Modena, the Torre della Ghirlandina and Piazza Grande are a UNESCO World Heritage Site since 1997, Modena is known in culinary circles for its production of balsamic vinegar. Modena lies on the Pianura Padana, and is bounded by the two rivers Secchia and Panaro, both affluents of the Po River and their presence is symbolized by the Two Rivers Fountain in the citys center, by Giuseppe Graziosi. The city is connected to the Panaro by the Naviglio channel, the Apennines begin some 10 kilometres from the city, to the south.
The commune is divided into four circoscrizioni and these are, Centro storico Crocetta Buon Pastore San Faustino Modena has a humid subtropical climate, with an average annual precipitation of 809 millimetres. Summers are warm and winters are chilly and wetter, with the possibility of snowfall and this climate is described by the Köppen climate classification as Cfa. From 1945 to 1992, Modena had a consecutive series of Communist mayors. From the 1990s, the city has been governed by center-left coalitions, at the April 2006 elections, the city of Modena gave about 50% of its votes to the Democratic Party. The legislative body of the municipality is the City Council which is composed by 35 members elected every five years, Modenas executive body is the City Committee composed by 9 assessors, the deputy-mayor and the mayor. The current mayor of Modena is Giancarlo Muzzarelli, member of the Democratic Party of Italy, the territory around Modena was inhabited by the Villanovans in the Iron Age, and by Ligurian tribes and the Gaulish Boii.
Livy described it as a fortified citadel where Roman magistrates took shelter, the outcome of the siege is not known, but the city was most likely abandoned after Hannibals arrival. Mutina was refounded as a Roman colony in 183 BC, to be used as a base by Marcus Aemilius Lepidus. In the 1st century BC Mutina was besieged twice, the first siege was by Pompey in 78 BC, when Mutina was defended by Marcus Junius Brutus. The city eventually surrendered out of hunger, and Brutus fled, in the civil war following Caesars assassination, the city was besieged again, this time by Mark Antony, in 44 BC, and defended by Decimus Junius Brutus. Octavian relieved the city with the help of the Senate, cicero called it Mutina splendidissima in his Philippics. It is said that Mutina was never sacked by Attila, for a dense fog hid it, as of December 2008, Italian researchers have discovered the pottery center where the oil lamps that lit the ancient Roman empire were made
They are made of an elastic material formed into the shape of a helix which returns to its natural length when unloaded. Under tension or compression, the material of a coil spring undergoes torsion, the spring characteristics therefore depend on the shear modulus, not Youngs Modulus. A coil spring may be used as a torsion spring, the material of the spring is thereby subjected to a bending moment, either reducing or increasing the helical radius. In this mode, it is the Youngs Modulus of the material determines the spring characteristics. Metal coil springs are made by winding a wire around a shaped former - a cylinder is used to form cylindrical coil springs, types of coil spring are, Tension/extension coil springs, designed to resist stretching. They usually have a hook or eye form at each end for attachment, compression coil springs, designed to resist being compressed. A typical use for compression coil springs is in car suspension systems, volute springs are used as heavy load compression springs. A strip of plate is rolled into the shape of both a helix and a spiral, when compressed, the strip is stiffer edge-on than a wire coil, but the spiral arrangement allows the turns to overlap rather than bottoming out on each other.
Torsion springs, designed to resist twisting actions, often associated to clothes pegs or up-and-over garage doors. Spring Helical Spring by Sándor Kabai at The Wolfram Demonstrations Project, Institute of Spring Technology Spring Manufacturers Institute, tutorial by Dave Silberstein. You Spring From Morning To Night, April 1949, Popular Science article on the basics of steel coil springs manufacturing
Italy, officially the Italian Republic, is a unitary parliamentary republic in Europe. Located in the heart of the Mediterranean Sea, Italy shares open land borders with France, Austria, San Marino, Italy covers an area of 301,338 km2 and has a largely temperate seasonal climate and Mediterranean climate. Due to its shape, it is referred to in Italy as lo Stivale. With 61 million inhabitants, it is the fourth most populous EU member state, the Italic tribe known as the Latins formed the Roman Kingdom, which eventually became a republic that conquered and assimilated other nearby civilisations. The legacy of the Roman Empire is widespread and can be observed in the distribution of civilian law, republican governments, Christianity. The Renaissance began in Italy and spread to the rest of Europe, bringing a renewed interest in humanism, exploration, Italian culture flourished at this time, producing famous scholars and polymaths such as Leonardo da Vinci, Galileo and Machiavelli. The weakened sovereigns soon fell victim to conquest by European powers such as France and Austria.
Despite being one of the victors in World War I, Italy entered a period of economic crisis and social turmoil. The subsequent participation in World War II on the Axis side ended in defeat, economic destruction. Today, Italy has the third largest economy in the Eurozone and it has a very high level of human development and is ranked sixth in the world for life expectancy. The country plays a prominent role in regional and global economic, military and diplomatic affairs, as a reflection of its cultural wealth, Italy is home to 51 World Heritage Sites, the most in the world, and is the fifth most visited country. The assumptions on the etymology of the name Italia are very numerous, according to one of the more common explanations, the term Italia, from Latin, was borrowed through Greek from the Oscan Víteliú, meaning land of young cattle. The bull was a symbol of the southern Italic tribes and was often depicted goring the Roman wolf as a defiant symbol of free Italy during the Social War. Greek historian Dionysius of Halicarnassus states this account together with the legend that Italy was named after Italus, mentioned by Aristotle and Thucydides.
The name Italia originally applied only to a part of what is now Southern Italy – according to Antiochus of Syracuse, but by his time Oenotria and Italy had become synonymous, and the name applied to most of Lucania as well. The Greeks gradually came to apply the name Italia to a larger region, excavations throughout Italy revealed a Neanderthal presence dating back to the Palaeolithic period, some 200,000 years ago, modern Humans arrived about 40,000 years ago. Other ancient Italian peoples of undetermined language families but of possible origins include the Rhaetian people and Cammuni. Also the Phoenicians established colonies on the coasts of Sardinia and Sicily, the Roman legacy has deeply influenced the Western civilisation, shaping most of the modern world
The Ferrari Daytona, officially designated the Ferrari 365 GTB/4, is a two-seat grand tourer produced by Ferrari from 1968 to 1973. It was introduced at the Paris Auto Salon in 1968 to replace the 275 GTB/4, the Daytona was succeeded by the mid-engined 365 GT4 Berlinetta Boxer in 1973. To this day, Ferrari itself only rarely refers to the 365 as the Daytona, unlike Lamborghinis then-new, mid-engined Miura, the Daytona was a traditional front-engined, rear-drive car. At a compression ratio of 9.3,1, it produced 357 PS, 0-60 mph acceleration was just 5.4 seconds. The five-speed manual transmission was mounted in the rear for optimal weight distribution, although a Pininfarina design, as with many previous Ferrari road cars styled by Leonardo Fioravanti, the 365 GTB/4 was radically different. Its sharp-edged styling resembled a Lamborghini more than a traditional Pininfarina Ferrari, early Daytonas featured fixed headlights behind an acrylic glass cover. A new U. S. safety regulation banning headlights behind covers resulted in retractable pop-up twin headlights in 1971, the generally accepted total number of Daytonas from the Ferrari club historians is 1,406 over the life of the model.
This figure includes 156 UK right-hand-drive coupés,122 factory-made spyders, all bodies except the first Pininfarina prototype were produced by Italian coachbuilder Scaglietti, which at the time already had a reputable record of working with Ferrari. Historically, and especially since the mid-1980s and early 1990s, there has mostly been a market price difference between a real berlinetta and a real spyder. Many berlinettas were turned into spyders by aftermarket mechanics, often to increase the monetary value or simply because of the owners preference for an open car. Differences in value have typically remained, even after the most skillful conversions, no Berlinettas were converted into Spyders by Scaglietti, Ferrari would not allow this, or now. The first racing version of the 365GTB/4 was prepared in 1969, Ferrari did not produce an official competition car until late in 1970. The official cars were built in three batches of five each, in 1970-1,1972 and 1973. They all featured a lightweight body making use of aluminium and fibreglass panels, the engine was unchanged from the road car in the first batch of competition cars, but tuned in the latter two batches.
The cars were not raced by the official Scuderia Ferrari team and they enjoyed particular success in the 24 Hours of Le Mans, with results including a 5th overall in 1971, followed by GT class wins in 1972,1973 and 1974. In 1972 Ferrari 365 GTB/4s took the first 5 places of the GT class, the final major success of the car was in 1979, when a 1973 car achieved a class victory in the 24 Hours of Daytona. In 1971, the Daytona gained fame when one was driven by Dan Gurney and Brock Yates in the inaugural Cannonball Baker Sea-To-Shining-Sea Memorial Trophy Dash. Showcasing the cars potential for sustained high speed travel, the pair won with an speed of 80.1 miles per hour