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32767 view(s)  Mazda's 787B was the first and until now last car that won LeMans that was powered by a rotary engine. Moreover it was also the first Japanese victory at LeMans. The unique 4 rotor engine produced 700 bhp and it outran its competitors; the Porsches, Peugeots and Jaguars.
With this victory Mazda capped 18 years of effort at LeMans and added a new page to the Japanese automotive history books.
The drivers Bertrand Gachot, Johnny Herbert and Volker Weidler completed 4923.200 km (3,059.79 miles) at an average speed of 205.133 km/h (127.49 mph)
The Mazda 787/787B were prototype Group C racing cars built for the 24 Hours of Le Mans and World Sportscar Championship, replacing the 767B. It used a 4-rotor R26B Wankel engine which produced over 700 hp (522 kW). First in the 1990 24 Hours of Le Mans, and later in the All Japan Sports Prototype Championship, the initial 787 was plagued with problems. At Le Mans neither 787 was able to finish due to electronics and oil failures, although an older 767B was able to finish. For 1991, Mazda upgraded the car to the 787B, and for the first time entered into the full 1991 World Sportscar Championship season.
1990 24 Hours of Le Mans
In 1990, as the Le Mans had its Mulsanne straight cut into threes, the FISA and ACO entered into a row over financial rights over the event, as a result Le Mans became a non-championship round. Mercedes-Benz who won the race in previous year as Sauber, pulled out of the race as a protest over the dealing over the two organisations, preferring to concentrate on the WSPC. Mazda, as under the rule amended in 1989 which stated that in order to compete in Le Mans, a team is required to enter all rounds, like many did the opposite by pulling out of the series and entered three cars especially for that year's race with a 787 which was like the earlier 767, it was the same car, except it had the 26B. Also, the car also had a carbon composite monocoque chassis with carbon fibre body, which was becoming commonplace for racecars and used the same Porsche designed 5-speed gearbox.
Like all previous models after the 737, the 787 was built by Advanced Composite Technology based in Heanor, Derbyshire in Britain and was designed by Englishman Nigel Stroud. Incidentally, the cars resembled the Porsche 956 which he was commissioned to design a clone for Richard Lloyd Racing in 1984. The track width was reduced 50mm to improve aerodynamics and to accommodate the increased engine output, the disc brakes were increased to 360mm.
The biggest change was the engine, specifically developed for this race, the R26B was lighter, smaller and more economical than its processor. The R26B Wankel engine benefited from a variable intake system, optimizing air intake for certain vehicle speeds.
Two periscope-shaped air intakes were mounted ahead of the rear wing. Each intake assembly was mated to a telescoping-pulley system which was able to vary the height of the protruding periscopes through a stroke of approximately six inches. The extension and retraction of the intakes was governed by the car's ECU computer depending on vehicle speed.
At high speed, the intakes were retracted to decrease drag and smooth airflow over the rear wing, and to reduce the restrictions on the air flow into the engine. At lower speeds, the intakes were extended in order to provide maximum positive pressure to the charge entering the rotors.
Also, it benefited from an extra spark plug on each rotor from the 767’s two, making the car more economical and improving combustion. An oil cooler was mounted at the front and the car’s aerodynamics was improved at the sides and top of the bodywork. Like all previous engine, it featured Peripheral Porting in order to achieve the high levels of power from a naturally aspirated motor.
Engine speed (RPM's) were deliberately kept low for longevity under the extreme stresses incurred during a 24-hour endurance race.
The 787 was reported to have a redline around 9000rpm. However, interviews with Mazda's 787 race engineers revealed that the power of the quad-rotor increased dramatically above 9000rpm. One engineer stated that the car could develop more than 930hp with a redline around 10,500rpm. Engineers also commented that during the post-race inspection and tear-down of the quad-rotor engine they discovered that all aspects of the engine were still in excellent condition and could have run another 24-hour race.
Having no experience in the race, the car covered over 2900 miles during tests between April and May in Fuji, Silverstone and Estoril
Unlike the previous year, they found they are no longer the sole team entrant, having to face against a sole MOMO backed privateer Porsche 962, to improve their chances, in May that year, Mazda installed legendary six time winner Jacky Ickx as consultant, and for the race entered a sole 767 of the previous year, numbered 203, driven by three of its leading factory veterans in Japan Takashi Yorino, Yoshimi Katayama and Yojiro Terada and fielded a pair of 787s for the non-Japanese drivers, number 201 for Volker Weidler, Bertrand Gachot and Johnny Herbert and number 202 for Stefan Johansson, David Kennedy and Pierre Dieudonné.
Car #201 was painted in white dominated by the logos of their sponsor 0123 a Japanese removal company which goes by the official name Art Moving Center and Art Sports, a sister company specialising in luxury car imports. Car #203 and #202 had an outrageous bright orange and green scheme, sporting the logos of Renown, an apparel manufacturer and Charge, a sister company of Renown, specialising in sportswear.
The car #202 would start at grid 22nd with #201 behind it, outqualifying two works Nissans and a selection of privateer C1 cars and #203 at 34th, at the middle of that selection before the C2 cars.
During the night of the race, the Porsche which hold the lead in its category for the last four hours until it retired with gearbox failure at 2am, leaving the class win open to Mazda, but into the morning at 3 and 5am subsequently, the 787s would fall victim to oil leak and scorched electrical loom, leaving the win to an old 767, finishing at 20th, the highest for a non-C1 car.
Both mechanical failures were caused by lack of cooling causing the ceramic coating in the new R26B engine's side housing to peel off which scored the housing walls.
Mazda would then return for the following year with an improved version called the 787B and would find themselves in numerous changes in not just the car, also with the management and the regulation.
1991 Season
Having being used to taking class wins since 1987, although no superior to the C1 category cars that dominates the top ten position, the IMSA GTP category that they had became accustomed to in previous years was merged into the newly renamed Category 2 against the C1 cars, meaning that the race will be run as a two category race. Also that year, the FIA prioritised the new 3.5 liter atmo formula that was introduced in 1989, known as Category 1, meaning that the category which the 787B was entered in, were forced to start behind the notoriously unreliable Cat.1 cars.
Now being in a second priority category, the category was still run to a fuel consumption formula, rather than the unlimited fuel allocation formula the series became accustomed to back in the US. Teams were allotted a specific amount of fuel, which was to be used for the entire race event - practice, qualifying and the race itself, unlike Cat.1 which had unlimited fuel allocation.
Not to be deterred, to show how serious Mazda was at winning the race, Takayoshi Ohashi’s Mazdaspeed concern would brought out by the company, giving them a full factory backing.
With the extra financial freedom, Ickx replaced long time campaigner Alan Docking Racing with French outfit Oreca despite being their second outing and their first since 1981 as a privateer, taking from Ickx’s experience with the team when he won the Pharaohs Rally in a works backed Lada Samara ran by them and felt their fast adapting skills made them the most suitable.
Ickx felt the car was running on too much weight for a Cat.2 car, so Ohashi would make a visit in Paris at the FIA’s headquarter to persuade them to allow the car to run with 50kg less than previously. This meant the car would weigh 170kg less than the standard 1000kg required by the competitors.
Mazda also continued to use the old 787 and 787B for the World Sportscar Championship and the JSPC, who was run by Mazdaspeed. Mazda would build three 787B, chassis 001 and 003 to be used in the Japanese championship and 002 would be extensively tested at Paul Ricard and not be used until the Le Mans race.
In order to win the 1991 race, Mazda engineers and the 787B had some new and significant obstacles to overcome. First, a year prior, two new chicanes had been installed on the Hunaudières Straight, breaking the nearly 3-mile long straightaway into three shorter segments, thus reducing top speeds from over 240mph (370 km/h) to roughly 210mph (338 km/h). This increased stress and wear on the brakes, having to stop the car from more than 200mph three times instead of just once as on the old layout, but reduced the chances of a tire blowout which was the purpose of the chicanes. It was the first time the car was equipped with carbon brakes.
1991 24 Hours of Le Mans
The 59th 24 Hours of Le Mans which was round 4 of the Sportscar World Championship was the first time the race took place at the entirely new pit complex much to the pleasure of pit crews and drivers, after several years of having to use the notoriously cramped area, which became associated with the film of the same name.
Mazdaspeed entered three cars and a spare, one of them was a 787 from the previous year, numbered #56, driven by Dieudonné, Yorino and Terada and two brand new 787B. One of them was driven by Maurizio Sandro Sala who replaced the newly retired Katayama, Johansson and Kennedy numbered #18 (001) and the #55 (002) car of Weidler, Herbert and Gachot making its only appearance in its only race. Unlike the other two cars which was painted in their standard blue stripes on white livery, #55 had an outrageous bright orange and green scheme and retained its sponsor who had been with them since 1988.
Though, not expected to be the favourite to win, the Mazdas started on 19th for #55, 23rd for #18 and 30th for #56, despite being the 12th, 17th and 24th fastest qualifier respectively. On the day before the race, realising the reliability of the cars from the Paul Ricard tests, taking advantage of its fuel economy and the favouritism by rival teams of cat.1 cars which was disappearing by lap after lap, this encouraged Ohashi to drop his usual conservative strategy in previous races and encourage the drivers of #55 to drive as if it was a sprint race.
As the race was underway, the #55 car was at third place with the #18 car behind it with 2 laps down, the #18 had a lower gear ratio setup meaning the car took up more fuel and was 20km/h slower.
The #55 would by night, move into second place when the Mercedes-Benz C11 of Michael Schumacher who was driving then, Fritz Kreutzpointner and Karl Wendlinger would spin off and later pit in with a gearbox problem.
By the 22nd hour, the #55 car would finally take the lead after the C11 of Alain Ferte was force to pit in with mechanical problems. Toward the last hour, Herbert was made to perform an extra shift, leading him and his 787B to win the race, completing 362 laps and covering 4932.2km. Mazda put their disappointment behind when their two other cars finished in the top tens, sixth place for car #18 behind three Jaguar XJR-12s and a sole Mercedes and eighth for #56. Herbert became so worn out that he had to be assisted out of the car and was unable to make it to the podium, leaving Weidler and Gatchot to take up the celebrations. He later in a magazine interview blamed a “dodgy” spaghetti he ate before his shift{fact}. The race was run without a hitch apart from a blown bulb at the headlights and the precautionary drivetrain change which was the only delay for the car.
It was believed that the secret behind its win was, whilst rivals, Nissan and Toyota spent that era, adopting and dropping new concepts, suppliers, engine configurations, drivers and even teams, failing when its victory was within grasp, Mazda stuck to the same basic engine/chassis concept, even the drivers.
They moved up from the old Group 4 category during their early days to the GTP category at the latter stages, only to delay their plans for victory in 1984 when their experimentation in C1 category with larger twin turbo on a 13B powered March 84G went awry in a WEC round at Fuji.
Also much of it was their commitment to the race as they had being competing since Mazda provided a rotary engine to a Chevron B16 in 1970, becoming the first Japanese manufacturer to be involved in the French classic to their first semi-works backed entry in 1973 and the following year with a Sigma Group 6 car to the first of their consecutive entry at the end of the decade, when they failed to qualify with a RX-7.
source: Wikipedia
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Models for Mazda 787B
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| Manufacturer |
Model |
Scale |
Dimensions (LxWxH) |
Wheelbase |
Front spur |
Rear spur |
| Kyosho Mini Z |
787B LM 91 Renown |
1/25 |
0.0x78.0x0.0 |
99.9 |
78.0 |
78.0 |
| Tamiya |
787B LM91 Renown |
1/24 |
99.9x83.0x40.0 |
99.9 |
78.2 |
80.0 |
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