A crankpin or crank journal is a journal in an engine or mechanical device. That is, the part of a axle that rests on bearings. In a reciprocating engine, the crankpin is the part of a crankshaft where the lower end of a connecting rod attaches. In a beam engine, a single crankpin is mounted on the flywheel. A crankpin is separated from its axle by a bearing; these are bushings or plain bearings, but less may be roller bearings. In a multi-cylinder engine, a crankpin can serve one or many cylinders, for example: In a in-line or opposed engine, each crankpin serves just one cylinder. In a V engine, each crankpin may serves two cylinders, depending on the design. In a radial engine, each crankpin serves an entire row of cylinders. There are three common configurations in crankpin design: If a crankpin serves only one cylinder the big end is a simple design, accommodating only one connecting rod; this design is the cheapest to produce, is used in: All single-cylinder engines. Most straight engines. All boxer engines.
Some V-twin engines. If a crankpin serves more than one cylinder the corresponding cylinders may have an offset, or may be articulated, to simplify the design of the big end bearing; this design is used in most V engines. If more than one cylinder is served by a single crankpin but there is no offset some or all of the connecting rods must be forked at the big end, or be articulated; this design provides better engine balance than designs with an offset, but requires extra complexity and cost in both design and manufacture, more weight or closer manufacturing tolerances to achieve the same strength and reliability. Any extra weight added to the big end itself carries a penalty of adding vibration and reducing balance; as the number of cylinders grows, the effect of the offset on balance becomes less important, forked connecting rods become less common. They are used in V-twin engines, notably including motorcycle engines, but in the past were found on a number of automobile and aero engines, such as the famous Rolls-Royce Merlin aero engine of the WWII era.
Articulated rods were used in older or exotic Vee engines, consist of rods that have a single master connecting rod attached to the crank pin, with the opposing connecting rod instead using a smaller bearing machined into the big end of the main connecting rod, instead of two dedicated crank journals. A similar but more complex design is used in radial engines, which have a master/slave connecting rod, with a single "master" connecting rod attached to the single crankpin, smaller bearings for each of the corresponding cylinders machined into the big end of the master rod. For more detail see the article on radial engines. Connecting rod Crankshaft Crankshaft deep rolling
Cisitalia Grand Prix
The Cisitalia Grand Prix is a single-seater car for the postwar 1.5-litre supercharged Grand Prix class, built by Italian sports car manufacturer Cisitalia and introduced in 1949. It was designed on behalf of Cisitalia by Porsche between 1946–47, is therefore known by its Porsche project number, Typ 360. An advanced design, it proved too complex to build for the small Italian firm—leading to a lengthy development and to the financial downfall of the company. Between Cisitalia's 1949 liquidation and the fact that supercharged engines were banned for the 1952 Formula One season, the car never raced; the car was commissioned by Piero Dusio in 1946. Dusio paid a large sum of money up front, part of, used to free Ferdinand Porsche from the French prison in which he was being held for ransom. Dusio gave Porsche only 16 months to complete the car which proved too short a time to sort out the advanced design; the Dr. Porsche designed unraced 1939 1,482.56 cc 2-stage Roots supercharged flat-12 Auto-Union had been projected to deliver 327 bhp at 9,000 rpm.
This provided the basis of the Cisitalia 360 car, built in Italy by Cisitalia personnel with help from former Porsche employee Robert Eberan von Eberhorst around a mid mounted supercharged 1,492.58 cc flat 12 engine giving a conservative 300 hp at 8,500 rpm and a top speed of 300 km/h. A enclosed streamlined body for fast circuits was planned giving over 200 mph. Bench tests showed about 385 bhp at 10,500 rpm; the chassis was of chromoly tubing and featured on/off four wheel drive with a sequential gear-shift and a rear-mounted transaxle sending power through a driveshaft to a front differential. Suspension was trailing arm in front De Dion tube in the rear. Porsche's experience with the pre-war Auto Union Grand Prix cars showed through in the layout and design of the Cisitalia to the extent that it has been referred to as the "E Type". By the time the only prototype was finished; the car languished in development until 1951, at one point being shipped off to Argentina to try to persuade president Juan Perón to invest in the company.
By 1952 Formula One rules had changed and while Dusio attempted to source a 2-liter motor for the car a lack of funds relegated one of the most advanced Grand Prix cars of its day to a few Formula Libre events and quick retirement. The car is on display in the Porsche Museum in Stuttgart. 8W The rear-engined revolution: Horses pushing the cart Cisitalia Museum
The Porsche 917 is a sports prototype race car developed by German manufacturer Porsche. The 917 gave Porsche its first overall wins at the 24 Hours of Le Mans in 1970 and 1971. Powered by the Type 912 flat-12 engine of 4.5, 4.9, or 5 litres, the 917/30 Can-Am variant was capable of a 0-62 mph time of 2.3 seconds, 0–124 mph in 5.3 seconds, a test track top speed of up to 240 mph. In 1971 the car featured in the Steve McQueen film Le Mans. In 2017 the car driven by McQueen in the film was sold at auction for $14m, a record price for a Porsche. For the 40th anniversary of the 917 in 2009 Porsche held a special celebration at the Goodwood Festival of Speed. In an effort to reduce the speeds generated at Le Mans and other fast circuits of the day by the unlimited capacity Group 6 prototypes the Commission Sportive Internationale announced that the International Championship of Makes would be run for three-litre Group 6 prototypes for four years from 1968 through 1971; this capacity reduction would serve to entice manufacturers who were building three-litre Formula One engines into endurance racing.
Well aware that few manufacturers were ready to take up the challenge the CSI allowed the participation of five-litre Group 4 sports cars, of which a minimum of 50 units had to be manufactured. This targeted existing cars like the aging Ford GT40 Mk. I and the newer Lola T70 coupe. In April 1968, facing few entrants in races, the CSI announced that the minimum production figure to compete in the sport category of the International Championship of Makes was reduced from 50 to 25, starting in 1969 through the planned end of the rules in 1971. With Ferrari absent in 1968 Porsche 908s and Ford P68s were entered there, with the Ford being a total failure; as a result, old 2.2-litre Porsche 907s won that category, with John Wyer's 4.7-litre Ford GT40 Mk. I taking wins at faster tracks. Starting in July 1968, Porsche made a surprising and expensive effort to take advantage of this rule; as they were rebuilding race cars with new chassis every race or two anyway, selling the used cars to customers, they decided to conceive and build 25 versions of a whole new car with 4.5-litre for the sport category with one underlying goal: to win its first overall victory in the 24 Hours of Le Mans on May 14, 1970.
In only ten months the Porsche 917 was developed, based on the Porsche 908. When Porsche was first visited by the CSI inspectors only three cars were completed, while 18 were being assembled and seven additional sets of parts were present. Porsche argued that if they assembled the cars they would have to take them apart again to prepare the cars for racing; the inspectors asked to see 25 assembled and working cars. On March 12, 1969, a 917 was displayed at the Geneva Motor Show, painted white with a green nose and a black No. 917. Brief literature on the car detailed a cash price of DM 140,000 £16,000 at period exchange rates, or the price of about ten Porsche 911s; this price did not cover the costs of development. On April 20 Porsche's head of motorsports Ferdinand Piëch displayed 25 917s parked in front of the Porsche factory to the CSI inspectors. Piëch offered the opportunity to drive any of the cars, declined; the car was designed by chief engineer Hans Mezger under the leadership of Ferdinand Piëch and Helmuth Bott.
The car was built around a light spaceframe chassis, permanently pressurised with gas to detect cracks in the welded structure. Power came from a new 4.5-litre air-cooled engine designed by Mezger, a combination of 2 of Porsche's 2.25L flat-6 engines used in previous racing cars. The'Type 912' engine featured a 180° flat-12 cylinder layout, twin overhead camshafts driven from centrally mounted gears and twin spark plugs fed from two distributors; the large horizontally mounted cooling fan was driven from centrally mounted gears. The longitudinally mounted gearbox was designed to take a set of five gears. To keep the car compact despite the large engine, the driving position was so far forward that the feet of the driver were beyond the front wheel axle; the car had remarkable technology. It was Porsche’s first 12-cylinder engine and used many components made of titanium and exotic alloys, developed for lightweight "Bergspider" hill climb racers. Other methods of weight reduction were rather simple, such as making the gear shift knob out of birch wood, some methods were not simple, such as using the tubular frame itself as oil piping to the front oil cooler.
There are at least eleven variants of the 917. The original version had a removable long tail/medium tail with active rear wing flaps, but had considerable handling problems at high speed because of significant rear lift; the handling problems were investigated at a joint test at the Österreichring by the factory engineers and their new race team partners John Wyer Engineering and after exhaustive experimentation by both groups, a shorter, more upswept tail was found to give the car more aerodynamic stability at speed. The changes were adopted into the 917K for Kurzheck, or "short-tail". In 1971, a variant of the 917K appeared with a less upswept tail and vertical fins, featured the concave rear deck that had proved so effective on the 1970 version of the 917L; the fins kept the clean downforce-inducing air on the top of the tail and allowed the angle of the deck to be reduced, reducing the drag in direct proportion. The result was a more attractive looking car that maintained down force for less drag and higher top speed.
Panhard was a French motor vehicle manufacturer that began as one of the first makers of automobiles. It was last a manufacturer of light military vehicles, its final incarnation, now owned by Renault Trucks Defense, was formed by the acquisition of Panhard by Auverland in 2005, by Renault in 2012. In 2018 Renault Trucks Defense and Panhard combined under a single brand called Arquus. Panhard was called Panhard et Levassor, was established as an automobile manufacturing concern by René Panhard and Émile Levassor in 1887. Panhard et Levassor sold their first automobile based on a Daimler engine license. Levassor obtained his licence from Paris lawyer Edouard Sarazin, a friend and representative of Gottlieb Daimler's interests in France. Following Sarazin's 1887 death, Daimler commissioned Sarazin's widow Louise to carry on her late husband's agency; the Panhard et Levassor license was finalised by Louise, who married Levassor in 1890. Daimler and Levassor became fast friends, shared improvements with one another.
These first vehicles set many modern standards. They used a clutch pedal to operate a chain-driven gearbox; the vehicle featured a front-mounted radiator. An 1895 Panhard et Levassor is credited with the first modern transmission. For the 1894 Paris–Rouen Rally, Alfred Vacheron equipped his 4 horsepower with a steering wheel, believed to be one of the earliest employments of the principle. In 1891, the company built its first all-Levassor design, a "state of the art" model: the Système Panhard consisted of four wheels, a front-mounted engine with rear wheel drive, a crude sliding-gear transmission, sold at 3500 francs; this was to become the standard layout for automobiles for most of the next century. The same year, Panhard et Levassor shared their Daimler engine license with bicycle maker Armand Peugeot, who formed his own car company. In 1895, 1,205 cc Panhard et Levassor vehicles finished first and second in the Paris–Bordeaux–Paris race, one piloted solo by Levassor, for 48¾hr. However, during the 1896 Paris–Marseille–Paris race, Levassor was fatally injured due to a crash while trying to avoid hitting a dog, died in Paris the following year.
Arthur Krebs succeeded Levassor as General Manager in 1897, held the job until 1916. He turned the Panhard et Levassor Company into one of the largest and most profitable manufacturers of automobiles before World War I. Panhards won numerous races from 1895 to 1903. Panhard et Levassor developed the Panhard rod, which came to be used in many other types of automobiles as well. From 1910 Panhard worked to develop engines without conventional valves, using under license the sleeve valve technology, patented by the American Charles Yale Knight. Between 1910 and 1924 the Panhard & Levassor catalogue listed plenty of models with conventional valve engines, but these were offered alongside cars powered by sleeve valve power units. Following various detailed improvements to the sleeve valve technology by Panhard's own engineering department, from 1924 till 1940 all Panhard cars used sleeve valve engines. Under the presidency of Raymond Poincaré, which ran from 1913 till 1920, Panhard & Levassor's 18CV and 20CV models were the official presidential cars.
During the war Panhard, like other leading automobile producers, concentrated on war production, including large numbers of military trucks, V12-cylinder aero-engines, gun components, large 75 and 105 diameter shells. The military were keen on the sleeve valve engined Panhard 20HP. General Joffre himself used two 35HP Panhard Type X35s with massive 4-cylinder 7,360 cc engines for his personal transport, these were to be seen by Parisians carrying military leaders between the front-line and the Élysée Palace. Following the return to peace in 1918, Panhard resumed passenger car production in March 1919 with the 10HP Panhard Type X19, which used a 4-cylinder 2,140 cc engine; this was followed three months by three more 4-cylinder models which will have been familiar to any customers whose memories pre-dated the war, but they now incorporated ungraded electrics and a number of other modifications. For the 15th Paris Motor Show, in October 1919, Panhard were displaying four models, all with four cylinder engines, as follows: Panhard Type X19 2,150 cc / 10 HP Panhard Type X31 2,275 cc / 12 HPPanhard Type X28 3,175 cc / 16 HP Panhard Type X29 4,850 cc / 20 HPBy 1925, all Panhard's cars were powered by Knight sleeve valve engines that used steel sleeves.
The steel sleeves were thinner and lighter than the cast iron ones, fitted in Panhard sleeve valve engines since 1910, this gave rise to an improved friction coefficient permitting engines to run at higher speeds. To reduce further the risk of engines jamming, the outer sleeves, which are less thermally stressed than the inner sleeves, were coated on their inner sides with an anti-friction material, employing a patented technique with which Panhard engineers had been working since 1923; this was one of several improvements applied by Panhard engineers to the basic Knight sleeve-valve engine concept. In 1925 a 4,800 cc model set the world record for an average of 185.51 km/h. A surprise appeared on the Panhard stand at the 20th Paris Motor Show in October 1926, in the shape of the manufacturer's first six-cylinder model since before the war; the new Panhard 16CV "Six" sat on a 3,540 mm wheelbase. At the show it was priced, at 58,000 francs. Of the nine models displayed for the 1927 mo
The Ferrari 158 was a Formula One racing car made by Ferrari in 1964 as a successor to the V6-powered Ferrari 156 F1. It was equipped with a bore and stroke of 67.0 mm × 52.8 mm. The 158 was the first Ferrari Formula One car to use a monocoque chassis. John Surtees drove the Ferrari 158 to win his only Formula One Drivers' World Championship, in 1964. Ferrari won the 1964 Formula One World Championship by competing in the last two races in cars painted not in the traditional Rosso corsa but in white and blue; these cars were entered by the factory-supported but unofficial NART team, rather than the Scuderia Ferrari factory team. This was done as a protest concerning arguments between Ferrari and the Automobile Club d'Italia regarding the homologation of a new mid-engined Ferrari race car. Ferrari built a flat-12 powered Formula One car using same chassis as the 158, designated the Ferrari 1512 or Ferrari 512 F1; the flat-12 engine was designed by Mauro Forghieri and displaced 1,489.63 cc with a bore and stroke of 56.0 mm × 50.4 mm.
This engine developed 220 bhp @ 12,000 rpm compared to the 210 bhp @ 11,000 rpm of the 158's V8 engine. This power output made it one of the most powerful 1.5-litre Formula One engines, second to Honda's RA271 V12. A total of three 1512 chassis were produced, numbered 0007, 0008 and 0009; the 1512, with its larger, more powerful engine, was designed to be competitive on the longest, fastest circuits of the Formula One season, such as Reims and Monza. In this role it complemented the lighter, nimbler V8-powered 158, more competitive on small, twisty circuits; the 1512 made its racing debut at the 1964 US Grand Prix at Watkins Glen, raced alongside the 158 during the remainder of 1964 and into 1965. Official website
Alfa Romeo Tipo 33
The Alfa Romeo Tipo 33 was a sports racing prototype raced by the Alfa Romeo factory-backed team between 1967 and 1977. These cars took part for Sport Cars World Championship, Nordic Challenge Cup and CanAm series. A small number of road going cars were derived from it in 1967, called Alfa Romeo 33 Stradale. With the 33TT12 Alfa Romeo won the 1975 World Championship for Makes, with the 33SC12 the 1977 World Championship for Sports Cars, taking the first place in all eight of the championship races. Alfa Romeo started development of the Tipo 33 in the early 1960s, with the first car being built in 1965, it was sent for additional changes to be made. It used an Alfa Romeo TZ2 straight-4 engine; the 2000 cc Tipo 33 mid-engined prototype debuted on 12 March 1967 at the Belgian hillclimbing event at Fléron, with Teodoro Zeccoli winning. The first version was named as “periscope” because it had characteristic air inlet, it was powered with a large-diameter tube frame. The original T33 proved unreliable and uncompetitive in the 1967 World Sportscar Championship season, its best result a 5th at the Nürburgring 1000, co-driven by Zeccoli and Roberto Bussinello.
In 1968, Alfa's subsidiary, created an evolution model called 33/2. A road version, dubbed Alfa Romeo 33 Stradale, was introduced. At the 24 Hours of Daytona, the Porsche 907 with 2.2L engines were dominating the overall race, but Alfa took the 2-litre class win, with Udo Schütz and Nino Vaccarella. Win was repeated at the Targa Florio, where Nanni Galli and Ignazio Giunti took second place overall, followed by teammates Lucien Bianchi and Mario Casoni. Galli and Giunti won the class at the Nürburgring 1000 km, where the 2.5L version finished for the first time, 4th place in the 3.0L class with Schütz and Bianchi. However, in most races, the Alfa drivers were outclassed by their Porsche rivals which used bigger engines. In 1968, the car was used by privateers, winning its class in the 1000km Monza, Targa Florio and Nürburgring races. At the end of season Alfa Romeo had finished third in the 1968 International Championship for Makes. A total of 28 cars were built during 1968, allowing the 33/2 to be homologated as a Group 4 Sports Car for 1969.
The Alfa Romeo 33/3 made its debut in 1969 at the 12 Hours of Sebring. The engine was enlarged to 2998 cc with 400 hp, which put the 33/3 in the same class as the Porsche 908 and the Ferrari 312P; the chassis was now a monocoque. The new car did poorly at Sebring and Alfa did not take part in Le Mans after Lucien Bianchi's death in a practice session; the car took a couple of wins in smaller competitions but overall the 1969 season was not a successful one, Alfa Romeo was placed seventh in the 1969 International Championship for Makes. In 1970 the bigger 5.0L Porsche 917 and Ferrari 512 dominated, yet Toine Hezemans and Masten Gregory took third overall at Sebring, Andrea De Adamich and Henri Pescarolo won their class in the 1000km Zeltweg, finishing second overall. In 1970, an Alfa T 33/3 was one of the "actors" of Steve McQueen's movie Le Mans, released in 1971. In 1971 the Alfa Romeo racing effort was successful. Rolf Stommelen and Nanni Galli won their class at the 1000km Buenos Aires, before taking another class win at Sebring.
De Adamich and Pescarolo won outright at the 1000km Brands Hatch, a significant result against the "invincible" 917s. They took a class win at Monza and another one at Spa. At the Targa Florio and Hezemans won outright, followed by teammates De Adamich and Gijs Van Lennep. Hezemans and Vaccarella won their class at Zeltweg, De Adamich and Ronnie Peterson won overall at Watkins Glen. Alfa Romeo finished the season second place in the championship. In 1972 the 5 litre Group 5 Sports Cars were banned and the 3 litre cars of Alfa Romeo and Matra, redesignated as Group 5 Sports Cars, competed together for outright victories. A 4 litre version was entered to 1972 and 1974 CanAm series by Otto Zipper, the driver was Scooter Patrick. Autodelta was one of entrants with T33/4 in season 1974; the T33/3 version was used in the CanAm series earlier. The 33 TT 12 appeared in 1973 with the Carlo Chiti-designed 12 cylinder 3.0L flat engine. The 1973 season was more or less development time and in 1974 the car won at Monza 1000 km and finished the season with second place in the championship.
It wasn’t until 1975 that, after years of trying, Alfa Romeo won the 1975 World Championship for Makes. The season was one of total domination with seven wins in eight races. Winning drivers were: Arturo Merzario, Vittorio Brambilla, Jacques Laffite, Henri Pescarolo, Derek Bell and Jochen Mass. For 1976 Autodelta was concentrating on other things and the car was used in competitions; the successor of the 33TT12 1976 was SC referring to SCatolato, a boxed chassis. The 3.0 L flat-12 engine now produced 520 bhp. With this car Alfa Romeo won the 1977 World Championship for Sports Cars, the 33SC12s driven by Arturo Merzario, Jean-Pierre Jarier and Vittorio Brambilla having won every race in the series. At the Salzburgring the car reached an average speed of 203.82 km/h. The SC12 Turbo was Alfa's first twin turbocharged 12 cylinder engine and it was introduced around the same time as Renault's Formula One turbo engine. In the Alfa Romeo engine e
Endurance racing (motorsport)
Endurance racing is a form of motorsport racing, meant to test the durability of equipment and endurance of participants. Teams of multiple drivers attempt to cover a large distance in a single event, with participants given a break with the ability to change during the race. Endurance races can be run either to cover a set distance in laps as as possible, or to cover as much distance as possible over a preset amount of time. One of the more common lengths of endurance races has been running for 1,000 kilometres, or six hours. Longer races can run for 1,000 miles, 12 hours, or 24 hours. Teams can consist of anywhere from two to four drivers per event, dependent on the driver's endurance abilities, length of the race, or the rules for each event. Coppa Florio was an Italian car race started in 1900, renamed in 1905 when Vincenzo Florio offered the initial 50 000 Lira and a cup designed by Polak of Paris; the Brescia race visited the route Brescia-Cremona-Mantova-Brescia. In 1908, the race used the Circuito di Bologna: Bologna-Castelfranco Emilia-Sant'Agata Bolognese-San Giovanni in Persiceto-Bologna.
Since 1914 most of the Coppa Florio was co-organized with the Targa Florio near Palermo, running four or five laps, 108 km each. The Targa Florio was an open road endurance automobile race founded in 1906- the track length of the last decades was limited to the 72 kilometres of the Circuito Piccolo delle Madonie, lapped 11 times; the Mille Miglia was an open-road endurance race which took place in Italy 24 times from 1927 to 1957. The world's first organized 24-hour automobile race event was held on a 1-mile oval track at Driving Park, Ohio on July 3–4, 1905. Beginning on the afternoon of July 3, four cars from Frayer-Miller, Pope-Toledo and White Steamer raced for a $500 silver trophy; the winning Pope-Toledo car covered 828.5 miles. A protest was filed by the Frayer-Miller and Peerless teams, alleging the Pope-Toledo was not owned by the driver, instead sent from the factory with an engine built for racing; the first 24-hour race to take place at a dedicated motorsport venue was at Brooklands, eleven days after its opening in 1907.
This would lead to the Double Twelve race. This format meant the race took place for 12 hours each between 8am to 8pm and between it, the cars were locked up overnight to prevent maintenance work from being performed on them; the 2001 Dakar Rally saw competitors cover a distance of 10,739 kilometres with a winning time of 70 hours over 20 days with three classes of cars and trucks. The 1992 Paris–Cape Town Rally covered a distance of 12,427 km; the 1994 edition saw competitors return for a distance of 13,379 km. The Expedition Trophy, first held in 2005, runs from Murmansk to Vladivostok, for a total distance of 12,500 km; the 1908 New York to Paris Race covered a distance of over 16,000 km, taking 169 days from February 12 to July 30. In the beginning of formalised endurance racing, the races tended to be for sports cars while the Grand Prix cars of the era began to evolve into the open wheel racing cars of today and ran over shorter distances. Over time sports cars began to evolve away from their roots as a production based alternative to pure-bred racing machines of Grand Prix cars, which led to the creation of GT and touring car racing classes, these classes continued to embrace the endurance format.
Multiple drivers per car was an early adaptation as the rigors of endurance racing overcome the abilities of most racing drivers to compete solo, although solo attempts on 24 hour races like Le Mans would continue into the 1950s. The various endurance formats were appealing to manufacturers, not only as alternatives to the expense of Grand Prix racing, but because of its increased relevance to road going models. In automobile endurance racing, three events have come to form a Triple Crown, they are considered three of the most challenging endurance races over the decades: the 24 Hours of Daytona, 12 Hours of Sebring, 24 Hours of Le Mans. Phil Hill was the first in 1964 to win the three races, Timo Bernhard the most recent. No driver has won the three events in the same year. Bold on year indicate. Strong spectator figures, media interest and television coverage of endurance racing's Triple Crown events has led to the establishment of several endurance racing series — thereby giving teams the opportunity of running their cars in Championship events throughout the year.
The FIA World Endurance Championship is an international sports car racing series organized by both the Automobile Club de l'Ouest and the Fédération Internationale de l'Automobile. It supersedes the Intercontinental Le Mans Cup run in 2010 and 2011, uses similar rules to the ALMS/USCC and ELMS below; the series features both Le Mans GT cars. The 24 Hours of Le Mans is included as a feature race; the other races are 6 hours long and take place in countries all over the world such as Bahrain, Brazil and the United States. The WEC is considered a revival of the defunct World Sportscar Championship which ended in 1992. An early championship was the Australian Endurance Championship, held since 1981; the WeatherTech SportsCar Championship is a US sports car racing series organized by the International Motor Sports Association. The season begins with