A gear train or gear set is a machine element of a mechanical system formed by mounting two or more gears on a frame such that the teeth of the gears engage.
71-680: The Rolls-Royce–Bentley L-series V8 engine is an engine introduced in 1959. Built in Crewe , it was used on most Rolls-Royce and Bentley automobiles in the four decades after its introduction, with its final application being the Bentley Mulsanne which ended production in 2020. With BMW 's acquisition of the rights to use the Rolls-Royce name in 1998, Rolls-Royce Motor Cars began using BMW supplied V12 engines but Bentley under Volkswagen Group ownership continued to use highly modified versions of
142-629: A crate engine and its successor the GM LS engine is dynamically unrelated to it, the Rolls-Royce/Bentley V8 could through 2020 have been considered to be the engine with the longest production run in history that was still fitted to a vehicle from factory. The power output of the 6.75-litre over the 6.25-litre version was not very significant at the outset, the emphasis having been on increased torque. The plethora of revisions introduced throughout its life were primarily to comply with emissions; one of
213-531: A normally aspirated BMW V12 engine, which has no technical similarities with the L410 engine. The Rolls-Royce Ghost introduced in 2010 uses a 6.6-litre twin-turbo V12. Under Volkswagen Group, the Bentley Arnage's BMW engine was phased out from 2000 to 2002 and the L410 engine was reintroduced in highly redeveloped form. The Arnage-derived Brooklands uses the most powerful version of the engine yet. Those models and
284-400: A gear train has two gears. The input gear (also known as the drive gear or driver ) transmits power to the output gear (also known as the driven gear ). The input gear will typically be connected to a power source, such as a motor or engine. In such an example, the output of torque and rotational speed from the output (driven) gear depend on the ratio of the dimensions of the two gears or
355-464: A pitch circle radius of 2 in (51 mm), the angular speed ratio R A B {\displaystyle R_{AB}} is 2, which is sometimes written as 2:1. Gear A turns at twice the speed of gear B . For every complete revolution of gear A (360°), gear B makes half a revolution (180°). In addition, consider that in order to mesh smoothly and turn without slipping, these two gears A and B must have compatible teeth. Given
426-678: A series of new models. 2003's introduction of the Bentley Continental GT was nominally to replace the previous Rolls-Royce-based Continental R and T , but was the first Bentley-only developed vehicle since the merging of the brands in 1931. Equipped with a 5,998 cubic centimetres (366.0 cu in ) (6.0 litre) twin-turbocharged W12 engine , which produces a DIN -rated motive power output of 560 metric horsepower (412 kW ; 552 bhp ) at 6,100 rpm , and torque of 650 newton-metres (479 lbf⋅ft ) at 1,600 rpm. Torsen -based permanent four-wheel drive
497-472: Is according to director of engineering Dr Ulrich Eichhorn : Today’s V8 is a descendant of the 1959 engine but massively improved. It now has over 100 percent more power, over 100 percent more torque, 40 percent less fuel consumption and produces 99.5 percent fewer emissions. With the end of production of Rolls-Royce badged cars in 2002, the factory was redeveloped to allow an expansion of the Bentley brand through
568-697: Is also less common with American V8 engines. Rolls-Royce however did use General Motors transmissions in their vehicles, notably the Hydramatic in Silver Cloud and the Turbo-Hydramatic in the Silver Shadow . The marine version of the engine (LM 841) was sold directly as a "complete power pack". It was rated as being able to produce 220 bhp (164 kW) at 4000 rpm continuously for 12 hours, with peak power of 240 bhp (179 kW) at 4200 rpm. It
639-407: Is called an idler gear. Sometimes, a single idler gear is used to reverse the direction, in which case it may be referred to as a reverse idler . For instance, the typical automobile manual transmission engages reverse gear by means of inserting a reverse idler between two gears. Idler gears can also transmit rotation among distant shafts in situations where it would be impractical to simply make
710-476: Is equal to twice the thickness of a tooth, In the United States, the diametral pitch P {\displaystyle P} is the number of teeth on a gear divided by the pitch diameter; for SI countries, the module m {\displaystyle m} is the reciprocal of this value. For any gear, the relationship between the number of teeth, diametral pitch or module, and pitch diameter
781-440: Is equivalently determined by the ratio of the number of teeth: In other words, the [angular] speed ratio is inversely proportional to the radius of the pitch circle and the number of teeth of gear A , and directly proportional to the same values for gear B . The gear ratio also determines the transmitted torque. The torque ratio T R A B {\displaystyle {\mathrm {TR} }_{AB}} of
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#1732870029049852-405: Is given by This shows that if the output gear B has more teeth than the input gear A , then the gear train amplifies the input torque. In this case, the gear train is called a speed reducer and since the output gear must have more teeth than the input gear, the speed reducer amplifies the input torque. When the input gear rotates faster than the output gear, then the gear train amplifies
923-495: Is given by: Since the pitch diameter is related to circular pitch as this means Rearranging, we obtain a relationship between diametral pitch and circular pitch: For a pair of meshing gears, the angular speed ratio , also known as the gear ratio , can be computed from the ratio of the pitch radii or the ratio of the number of teeth on each gear. Define the angular speed ratio R A B {\displaystyle R_{AB}} of two meshed gears A and B as
994-458: Is indoors. In preparation for World War II , Rolls-Royce and the British government searched for a location for a shadow factory to ensure production of aero-engines. Crewe, with its excellent road and rail links, as well as being located in the northwest away from the aerial bombing starting in mainland Europe, was a logical choice. Crewe also had extensive open farming land. Construction of
1065-425: Is not connected directly to either the motor or the output shaft and only transmits power between the input and output gears. There is a third gear (Gear B ) partially shown in the upper-right corner of the photo. Assuming that gear is connected to the machine's output shaft, it is the output or driven gear. Considering only gears A and I , the gear ratio between the idler and the input gear can be calculated as if
1136-443: Is rounded up to describe it as the six and a quarter litre engine. When new, the Rolls-Royce/Bentley V8 was rumoured to be an American engine design licence-built, but it was developed in-house by Rolls-Royce and Bentley engineers. This can be seen in its design characteristics, with features like an aluminium alloy cylinder block with wet liners , gear-driven camshaft, (initially) outboard spark plugs and porting inspired by
1207-786: Is standard, allowing it to accelerate from 0 to 100 kilometres per hour (0.0 to 62.1 mph) in 4.8 seconds, and go on to reach a top speed of 318 kilometres per hour (197.6 mph). 2005 saw the introduction of the 4 door derived version, the Continental Flying Spur . Due to a lack of capacity at the Crewe upon the car's introduction, some Flying Spurs destined for markets other than the USA and UK were built at Volkswagen 's Transparent Factory in Dresden , Germany. This arrangement ended in 2006, when all assembly work reverted to Crewe. Unveiled at
1278-424: Is the diameter of a gear's pitch circle, measured through that gear's rotational centerline, and the pitch radius r {\displaystyle r} is the radius of the pitch circle. The distance between the rotational centerlines of two meshing gears is equal to the sum of their respective pitch radii. The circular pitch p {\displaystyle p} is the distance, measured along
1349-399: Is the gear ratio of the gear train, the input torque T A {\displaystyle T_{A}} applied to the input gear A and the output torque T B {\displaystyle T_{B}} on the output gear B are related by the same gear or speed ratio. The torque ratio of a gear train is also known as its mechanical advantage ; as demonstrated,
1420-465: The Rolls-Royce Merlin aircraft engine. The bore spacing of 4 + 3 ⁄ 4 in (120.7 mm) was unlike any American V8 engine, with the sole exceptions of Buick's big block V-8 and AMC American Motor's V-8 line which share the same identical 4.750 bore centers, and the firing order was 1-5-4-8-6-3-7-2 something uncommon in any period American OHV V8. The deep skirted crankcase design
1491-528: The 2009 Pebble Beach Concours d'Elegance , the Bentley Mulsanne is notable as the first flagship car to be independently designed by Bentley Motors in nearly 80 years; the last being W.O. Bentley 's iconic 8 litre model in 1930. Replacing the Arnage, and using a modified V8 to meet Euro V emissions regulations, the car went on sale during 2010. Since 2015, the Bentley Bentayga has been assembled at
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#17328700290491562-537: The 2020 twin-turbo 6.75-litre engine produced over 150% more motive power and torque than at the beginning of its life, had 40% better fuel economy , and produced 99.5% less exhaust emission . In the Brooklands and Mulsanne , the 6.75-litre engine produced 395 kW (537 PS; 530 bhp) and 1,050 N⋅m (774 lb⋅ft) of torque. The 6 + 3 ⁄ 4 litres (412 cu in) 512 PS (377 kW; 505 bhp) engine used in Bentley Mulsanne
1633-577: The 6.75-litre for the Bentley Arnage . BMW V8 engines were used exclusively in the Arnage from 1998 to 2000. Vickers plc placed the Rolls-Royce and Bentley car manufacturing business up for sale in 1997, shortly after the introduction of the new models, in order that they could focus on their core defence business. BMW were initially expected to agree to a purchase quickly given their existing engine and component supply contracts with Rolls-Royce and Bentley, together with their recent history of expansion in
1704-562: The Bentley R-Type and S-Type differed significantly from the corresponding Rolls-Royce models, the 1965 Bentley T-series / Rolls-Royce Silver Shadow differed only in badges and radiator grills. The Bentley models even used a Rolls-Royce badged engine. As a result, fewer Bentleys were sold, making them more valuable today. The Bentley T-series / Rolls-Royce Silver Shadow were the first models with monocoque construction and four-wheel disc brakes . The 1980 badge engineered Bentley Mulsanne
1775-532: The Bentley brand and the Crewe factory but not the Rolls-Royce brand which would return to Rolls-Royce Group in the event of a sale. BMW, Mercedes-Benz , and the Volkswagen Group expressed interest, but Volkswagen eventually outbid BMW, while Mercedes withdrew, instead deciding to revive the Maybach brand for their luxury cars. However, BMW did buy the Rolls-Royce brand name from Rolls-Royce. They also agreed with
1846-559: The L series on its Arnage , Azure , Brooklands and Mulsanne models, with VAG W-12 and V8 engines being used in its Continental GT , Flying Spur and Bentayga models. The first engine of V8 configuration was developed in 1904 by Léon Levavasseur in France and used for speedboat racing. Rolls-Royce premiered the world's first automobile production V8 engine in 1905 for the Rolls-Royce V-8 Legalimit – governed not to exceed
1917-542: The L410 continued in production powering Rolls-Royces up to 1998 and Bentleys into the 21st century. Bentley, under Volkswagen ownership since 1998, continues to develop the L410 for its range of cars. Rolls-Royce ceased using the L410 with the switch to BMW ownership of that brand in March 1998 and introduction of a BMW sourced V12 engine in the Rolls-Royce Silver Seraph . Since 1998 therefore, development and use of
1988-550: The L410 engine can be said to have been exclusively a Bentley enterprise. The factory nomenclature for the L-series V8 engines, in chronological order, is as follows: The engine was of an overhead valve (OHV) design, angled at 90 degrees, and featured a central camshaft and wedge -shaped combustion chambers . As initially released, the bore x stroke was 4.1 in × 3.6 in (104.14 mm × 91.44 mm) and displaced 6,230 cc (380 cu in), which
2059-522: The Renaissance scientist Georgius Agricola show gear trains with cylindrical teeth. The implementation of the involute tooth yielded a standard gear design that provides a constant speed ratio. The pitch circle of a given gear is determined by the tangent point contact between two meshing gears; for example, two spur gears mesh together when their pitch circles are tangent, as illustrated. The pitch diameter d {\displaystyle d}
2130-729: The Rolls-Royce V8 which it owned the rights to, resulting in the sub-division of the Bentley Arnage into the Green-label (powered by the BMW V8), and the Red-label (powered by the redeveloped RR V8). Very quickly the Red-label out sold the Green-label, and resulted in Volkswagen further developing the engine. Today's version shares no components with the original version used in the S1, but shares its lineage and
2201-400: The Rolls-Royce brand until the end of 2002, when Rolls-Royce Motors transferred to BMW control, leaving VW with the Bentley marque, the factory, and ownership of all current models (although production of the Rolls-Royce Silver Seraph was discontinued). BMW no longer owns the rights to produce any pre-2003 Rolls-Royce or Bentley engines. The Rolls-Royce Phantom VII and its derivatives use
Rolls-Royce–Bentley L-series V8 engine - Misplaced Pages Continue
2272-496: The UK, with the purchase of Rover Group . BMW would go on to warn Mayflower Corporation that it would cease to supply engines should they purchase Vickers or Rolls-Royce and Bentley, and that it considered itself the best buyer for the company in late 1997. BMW would reach an agreement with Vickers to acquire Rolls-Royce and Bentley Motor Cars on 31 April 1998 for £340m, but this was superseded by an agreement for Volkswagen Group to acquire
2343-527: The Volkswagen Group a handover plan, which would complete at the end of 2001. In 2000, BMW's new Rolls-Royce Motor Cars division announced that they would build a new manufacturing plant at the historic Goodwood Estate in West Sussex . Having been heavily underinvested for some time, Volkswagen Group invested £500M in the two years after its takeover of the Crewe plant. It also revived development on
2414-595: The aero engine manufacturer Rolls-Royce plc following the 1973 divestment of the car manufacturing business, and Rolls-Royce plc were not prepared to allow Volkswagen to license this crucial intellectual property. Three way negotiations between Volkswagen Group, BMW and Rolls-Royce plc resulted in BMW purchasing the rights to the Rolls-Royce brand and badge from Rolls-Royce plc for £40m. Rolls-Royce plc, who had been involved in an aero engine joint venture with BMW since 1990 consistently supported their long time business partner during
2485-437: The angular rotation of all the gears in the gear train are defined by the angle of the input gear. The input torque T A {\displaystyle T_{A}} acting on the input gear A is transformed by the gear train into the output torque T B {\displaystyle T_{B}} exerted by the output gear B . Let R A B {\displaystyle R_{AB}} be
2556-666: The bidding process for Rolls-Royce and Bentley Motors. German politicians brokered a deal between Volkswagen Group and BMW to ensure BMW would continue to supply engines, transmissions and key components for a five-year period, with BMW sub-licensing the necessary intellectual property to allow Volkswagen to build and sell the Rolls-Royce Silver Seraph. It was considered damaging to the German automotive industry for Volkswagen and BMW to engage in legal action against each other. The deal reached allowed Volkswagen Group to retain use of
2627-524: The business for £430m, which was announced eight days later, on 7 May 1998. The Volkswagen sale appeared to have collapsed later in May, with BMW being announced as the preferred buyer for the Rolls-Royce and Bentley business 1 June 1998, subject to shareholder approval. Such approval was not forthcoming and the BMW deal collapsed when Volkswagen subsidiary Audi agreed to buy Cosworth from Vickers for £120m only if Volkswagen Group's £430m bid for Rolls-Royce and Bentley
2698-716: The convertible Bentley Azure are produced alongside the Bentley Mulsanne and smaller Bentleys based on the Continental GT , which use the Volkswagen Group W-12 engine. Bentley Crewe Bentley Crewe , also named the Pyms Lane site after the street it is located on; is the headquarters and design and manufacturing centre of Bentley Motors Limited on the outskirts of Crewe , Cheshire , England . The site covers an area of 521,111 m (5,609,190 sq ft), of which 166,930 m (1,796,800 sq ft)
2769-466: The displacement to 4.9 litres, that engine being known as the B61. The need for a new engine was recognised by Rolls-Royce in the early 1950s and its development began in 1952, bearing no relation to the 1905 Rolls-Royce V8. The result was a series of V8 engines known as the L series, more specifically the "L410" for its bore size of 4.1 in (104.14 mm), in keeping with company practice. Developments of
2840-433: The distant gears larger to bring them together. Not only do larger gears occupy more space, the mass and rotational inertia ( moment of inertia ) of a gear is proportional to the square of its radius. Instead of idler gears, a toothed belt or chain can be used to transmit torque over distance. If a simple gear train has three gears, such that the input gear A meshes with an intermediate gear I which in turn meshes with
2911-419: The drive gear ( A ) must make 1.62 revolutions to turn the output gear ( I ) once. It also means that for every one revolution of the driver ( A ), the output gear ( I ) has made 13 ⁄ 21 = 1 ⁄ 1.62 , or 0.62, revolutions. The larger gear ( I ) turns slower. The third gear in the picture ( B ) has N B = 42 {\displaystyle N_{B}=42} teeth. Now consider
Rolls-Royce–Bentley L-series V8 engine - Misplaced Pages Continue
2982-403: The driver and driven gear. If the driver gear moves in the clockwise direction, then the driven gear also moves in the clockwise direction with the help of the idler gear. In the photo, assume the smallest gear (Gear A , in the lower right corner) is connected to the motor, which makes it the drive gear or input gear. The somewhat larger gear in the middle (Gear I ) is called an idler gear. It
3053-562: The engine capacity to 6,750 cc (412 cu in). Known as the Six and Three-Quarter Litre or simply the Six and Three-Quarter , it is the most widely produced and well known of all the versions. The Rolls-Royce/Bentley V8 is the engine with the longest production run in history, surpassing the Chevrolet Small-block V8 . As the Chevrolet small-block engine is now only available as
3124-473: The factory produced its first motor car, the Ivan Evernden designed Bentley Mark VI which was based on the short lived Bentley Mark V . It was the first Bentley (or Rolls-Royce) with a standard pressed-steel body rather than different bodies designed and made by bespoke coach builders. The Bentley Mark VI was the most successful Bentley ever manufactured: Crewe produced more than 5,000 Mark VIs, which equaled
3195-579: The factory started on a 60-acre area on the potato fields of Merrill's Farm in July 1938, with the first Rolls-Royce Merlin aero-engine rolling off the production line five months later. A total 25,000 Merlin engines were produced, employing 10,000 people at its peak in 1943. With the war in Europe over and the general move towards the then new jet engines , Rolls-Royce concentrated its aero engine operations at Derby and moved motor car operations to Crewe. In 1946
3266-541: The factory. Gear train Gear teeth are designed to ensure the pitch circles of engaging gears roll on each other without slipping, providing a smooth transmission of rotation from one gear to the next. Features of gears and gear trains include: The transmission of rotation between contacting toothed wheels can be traced back to the Antikythera mechanism of Greece and the south-pointing chariot of China. Illustrations by
3337-403: The gear ratio and speed ratio of a gear train also give its mechanical advantage. The mechanical advantage M A {\displaystyle \mathrm {MA} } of a pair of meshing gears for which the input gear A has N A {\displaystyle N_{A}} teeth and the output gear B has N B {\displaystyle N_{B}} teeth
3408-412: The gear ratio for the subset consisting of gears I and B , with the idler gear I serving as the input and third gear B serving as the output. The gear ratio between the idler ( I ) and third gear ( B ) R I B {\displaystyle R_{IB}} is thus or 2:1. The final gear ratio of the compound system is 1.62×2≈3.23. For every 3.23 revolutions of the smallest gear A ,
3479-415: The gear ratios of the two subsets are multiplied: Notice that this gear ratio is exactly the same as for the case when the gears A and B engage directly. The intermediate gear provides spacing but does not affect the gear ratio. For this reason it is called an idler gear. The same gear ratio is obtained for a sequence of idler gears and hence an idler gear is used to provide the same direction to rotate
3550-424: The gear train is defined as the ratio of its output torque to its input torque. Using the principle of virtual work , the gear train's torque ratio is equal to the gear ratio, or speed ratio, of the gear train. Again, assume we have two gears A and B , with subscripts designating each gear and gear A serving as the input gear. For this analysis, consider a gear train that has one degree of freedom, which means
3621-524: The gear train. The speed ratio R A B {\displaystyle R_{AB}} of the gear train can be rearranged to give the magnitude of angular velocity of the output gear in terms of the input gear velocity. Rewriting in terms of a common angular velocity, The principle of virtual work states the input force on gear A and the output force on gear B using applied torques will sum to zero: This can be rearranged to: Since R A B {\displaystyle R_{AB}}
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#17328700290493692-458: The gears will come into contact with every tooth on the other gear before encountering the same tooth again. This results in less wear and longer life of the mechanical parts. A non-hunting gear set is one where the teeth counts are insufficiently prime. In this case, some particular gear teeth will come into contact with particular opposing gear teeth more times than others, resulting in more wear on some teeth than others. The simplest example of
3763-437: The idler gear was the output gear. The input gear A in this two-gear subset has 13 teeth ( N A {\displaystyle N_{A}} ) and the idler gear I has 21 teeth ( N I {\displaystyle N_{I}} ). Therefore, the gear ratio for this subset R A I {\displaystyle R_{AI}} is This is approximately 1.62 or 1.62:1. At this ratio, it means
3834-468: The input torque. Conversely, if the output gear has fewer teeth than the input gear, then the gear train reduces the input torque; in other words, when the input gear rotates slower than the output gear, the gear train reduces the input torque. A hunting gear set is a set of gears where the gear teeth counts are relatively prime on each gear in an interfacing pair. Since the number of teeth on each gear have no common factors , then any tooth on one of
3905-459: The legal speed limit in Britain at the time of 20 mph (32 km/h). It was not a success, with only three made and just one sold, which was soon returned to the factory to be scrapped. It was another decade before Cadillac pioneered a mass production V8-engined automobile. Rolls-Royce acquired Bentley in 1931 and continued to use Bentley engines alongside their own for a time, although none
3976-440: The most notable changes was the new firing order of 1-5-4-8-6-3-7-2 introduced in 1987. With improved tuning and the addition of turbochargers, the 6.75-litre became one of the world's most powerful automobile engines and enormously enhanced the image of Bentley as a sporting car maker. The process of evolving the engine was gradual and continuous; by 2006 almost all the 1959-specification engine components had been upgraded, so that
4047-436: The number of teeth N {\displaystyle N} : The thickness t {\displaystyle t} of each tooth, measured through the pitch circle, is equal to the gap between neighboring teeth (also measured through the pitch circle) to ensure the teeth on adjacent gears, cut to the same tooth profile, can mesh without interference. This means the circular pitch p {\displaystyle p}
4118-490: The output gear B , then the pitch circle of the intermediate gear rolls without slipping on both the pitch circles of the input and output gears. This yields the two relations The speed ratio of the overall gear train is obtained by multiplying these two equations for each pair ( A / I and I / B ) to obtain This is because the number of idler gear teeth N I {\displaystyle N_{I}} cancels out when
4189-442: The pitch circle, between one tooth and the corresponding point on an adjacent tooth. The number of teeth N {\displaystyle N} per gear is an integer determined by the pitch circle and circular pitch. The circular pitch p {\displaystyle p} of a gear can be defined as the circumference of the pitch circle using its pitch radius r {\displaystyle r} divided by
4260-749: The ratio of the magnitude of their respective angular velocities: Here, subscripts are used to designate the gear, so gear A has a radius of r A {\displaystyle r_{A}} and angular velocity of ω A {\displaystyle \omega _{A}} with N A {\displaystyle N_{A}} teeth, which meshes with gear B which has corresponding values for radius r B {\displaystyle r_{B}} , angular velocity ω B {\displaystyle \omega _{B}} , and N B {\displaystyle N_{B}} teeth. When these two gears are meshed and turn without slipping,
4331-421: The ratio of the tooth counts. In a sequence of gears chained together, the ratio depends only on the number of teeth on the first and last gear. The intermediate gears, regardless of their size, do not alter the overall gear ratio of the chain. However, the addition of each intermediate gear reverses the direction of rotation of the final gear. An intermediate gear which does not drive a shaft to perform any work
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#17328700290494402-428: The same tooth and gap widths, they also must have the same circular pitch p {\displaystyle p} , which means This equation can be rearranged to show the ratio of the pitch circle radii of two meshing gears is equal to the ratio of their number of teeth: Since the angular speed ratio R A B {\displaystyle R_{AB}} depends on the ratio of pitch circle radii, it
4473-401: The speed ratio, then by definition Assuming the gears are rigid and there are no losses in the engagement of the gear teeth, then the principle of virtual work can be used to analyze the static equilibrium of the gear train. Because there is a single degree of freedom, the angle θ of the input gear completely determines the angle of the output gear and serves as the generalized coordinate of
4544-626: The total number of Bentleys made in the 20 years before World War II. The Derby designed Bentley R Type was produced until 1955 when it was succeeded by the Bentley S1 / Rolls-Royce Silver Cloud , the first car wholly designed, developed, and built at Crewe. It was also the last Bentley fitted with a six-cylinder engine. Its successor, the Bentley S2 , used the Crewe designed and developed 6.25-litre, all-aluminium, Rolls-Royce V8 engine , which has remained in production in various forms ever since. While
4615-422: The traditional wealthy. The result was a surge in Bentley sales, which by 1985, had over taken Rolls-Royce sales for the first time since car production moved to Crewe. 1998 brought the launch of the all-new Bentley Arnage / Rolls-Royce Silver Seraph , the last dual-brand model, powered by a BMW 4.4 litre twin-turbo V8 engine. The same year, Vickers announced its intention to sell its car division, which included
4686-462: The velocity v {\displaystyle v} of the tangent point where the two pitch circles come in contact is the same on both gears, and is given by: Rearranging, the ratio of angular velocity magnitudes is the inverse of the ratio of pitch circle radii: Therefore, the angular speed ratio can be determined from the respective pitch radii: For example, if gear A has a pitch circle radius of 1 in (25 mm) and gear B has
4757-656: Was a V8. Prior to World War II , Rolls-Royce had developed a 7.3-litre V-12 for the Phantom III , which was succeeded by the inlet-over-exhaust B60 straight-6 and B80 straight-8 series of engines. The B80 powered the Phantom IV limousine, whilst the 4.3-litre B60 was used until 1955 to power the Rolls-Royce Silver Wraith and Silver Dawn and the Bentley Mark VI . The B60's bore was enlarged in 1955, increasing
4828-435: Was accepted. Volkswagen's bid to purchase Rolls-Royce and Bentley Motors from Vickers was finally accepted, and a price of £479m was paid, but by the end of July 1998, it became apparent that they would be unable to market any vehicle under the Rolls-Royce brand or use the Rolls-Royce badge on any of their products, as they had not acquired the rights to the Rolls-Royce brand name or the Rolls-Royce badge, which were retained by
4899-449: Was available with either direction of crankshaft rotation to suit port or starboard propellers. Engine cooling was closed loop glycol with heat exchangers to pumped sea water. It was supplied complete with a BorgWarner "velvet drive" gearbox . Starting in 1970 for the 1971 model year, the stroke of the V8 engine was increased from 3.6 to 3.9 in (91.44 to 99.06 mm), thereby increasing
4970-478: Was built at Crewe plant, and took nearly 30 hours to build. The twin-turbo V8 engine was cast at Bridgnorth , Shropshire , England and fully machined and partially assembled at the company's machining facility in Telford , Shropshire, England. BMW began supplying Rolls-Royce and Bentley with engines in 1998, specifically a V12 engine for the Rolls-Royce Silver Seraph and a twin-turbo 4.4-litre V8 engine to replace
5041-660: Was the last Bentley to undersell its Rolls-Royce sister, in this case the Rolls-Royce Silver Spirit . When the Rolls-Royce Motor Car division was sold to Vickers plc in 1980, Bentley changed its image, resulting in the 140 miles per hour (230 km/h) Bentley Mulsanne Turbo , nicknamed the "Crewe missile", which accelerated faster than some Ferraris . After this point, while the two marques looked similar, Bentleys were designed to appeal typically to wealthy businessmen, while Rolls-Royce maintained their appeal to
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