DAVID BATTLES GOLIATH - MAZDA'S 787B
During Japan’s pinnacle of economic strength through the late eighties and early nineties, various Japanese automakers achieved great victories in wide-ranging auto racing series around the world.
The engines by Honda dominated Formula One; the Skyline GT-R32 by Nissan controlled Group A races around the world; and Mitsubishi continued to conquer the Paris-Dakar. The only race that the Japanese automakers had yet to infiltrate was the Le Mans 24 Hours.
Since the eighties, Toyota, Nissan and Mazda were all active in the World Sportscar Championship, and the FIA categorised their cars as prototypes for Group C. These machines were pitted against many participating manufacturers, but most formidable were a handful of European motorsports giants, such as Porsche, Jaguar, Mercedes and Peugeot. If this collection of sports car entries were judged by their marques' domination of motor sport history and prestige, these European brands far overshadowed their challengers from the Orient... but there have been wonderful exceptions, and indeed, one special year, it was a new David who killed Goliath.
Le Mans history records this exception as the Mazda 787B, which won the 1991 Le Mans 24 Hours. But this exception, wasn’t a fluke. The durability of Mazda’s rotary engine was proven long before it earned its glory from Le Mans.
From the day when Toyo Kogyo, as Mazda used to be known, purchased the rotary technology from NSU Motorenwerke AG from West Germany, 1961, the automaker has actively sought to refine its power and durability through racing. One example would be the Cosmo Sport, which took on the 84-hour long endurance race, Marathon De La Route, in on the Nurburgring’s Nordschleife twice, finishing fourth once. Another outstanding example of Mazda’s rain history can be found in the early eighties, when famous English racers Tom Walkinshaw and Win Percy won at the Spa 24 Hours and the BTCC with the RX-7.
Yet, winning the 24 Hours of Le Mans would be challenge on a completely monumental level.
Mazda sent two of its 717C prototypes, each fitted with 2-rotor Wankel engines to compete in Group C at the 1983 Le Mans event. Mazda was the only Japanese entry, and the two cars finished twelfth and eighteenth. Encouraged, the automaker continued to participate in Le Mans in the following years which saw a steady performance evolution from the double rotor 717C through the 3-rotor 757, to eventually the 4-rotor 787/B. While Mazda's endurance participation saw them going respect, they were never seen as the strongest Japanese entrant. It was everyone’s consensus that the first Japanese automaker to win the Le Mans 24 Hour would be Toyota, or perhaps Nissan; Mazda wasn’t even considered. After all, Toyota and Nissan were the two largest automakers in Japan, and their funding and manpower in Group C were many multiples of yen compared to Mazda.
In 1991, Mazda brought their newly designed 787 to Le Mans. Similar to the previous prototype race car, the chassis of the 787 was created by British designer, Nigel Stroud. The monocoque was made in the UK, and later shipped to Japan, where it was assembled with the engine and other components at the Mazdaspeed racing headquarters. The whole chassis was constructed with carbon fibre under a honeycomb structure. For ’91, the suspension geometry was changed to accommodate larger and wider tires. In addition, carbon brake discs were implemented for the first time on a Mazda prototype car.
According to Nobuhiro Yamamoto, who was the chassis engineer for the Mazda 787B, and now the project manager for the MX-5 car series, the team had accumulated years of competition experience, particularly studying the data from the 1990 event. Through their careful analysis, they calculated that even under the most ideal circumstances, the 787 would only be able to finish 352 laps at the Circuit de la Sarthe, which was equivalent to the number of laps that the Alpha Racing Team’s Porsche 962C achieved as the second runner-up. In order for Mazda to win the 1991 Le Mans, they estimated they would need at least 367 laps.
The 1991 24 Hours Le Mans event came under new competition formula rules as FIA, the official race organiser, was actively pursuing an integration of the 3.5-liter naturally aspirated engine, in order for the race to also be in line with F1 regulations. Although TWR-Jaguar, Mercedes-Benz and Peugeot all built cars to the new regulations for the 1991 championship series, the amount of privateer teams was low and there was simply not enough of these new cars to fill the grid. The FIA allowed the first 10 spaces on the grid to be reserved for the fastest qualifying 3.5L cars from the World Sportscar Championship, while the rest of the field was made up of older formula Group C cars. At the same time, the new race formula enforced stricter fuel usage restrictions. So, along with the goal of enhancing horsepower and track modifications which reduced lap times by seven seconds, each team was also required to reduce fuel consumption.
The 13J 4-rotor engine used by the 767 race car in 1988 had a maximum 600 horsepower. The later modified 767B had a thirty horsepower upgrade, and the 787 in 1990 improved further. Yet, for 1991 Mazda believed they needed even more power, and attempted to increase the improved 787B’s R26B engine output by 100 more horsepower, to 750. It seemed an almost impossible mission, yet the engineers discovered modifications such as increasing the spark plugs per chamber from two to three, as well as implementing variable intake trumpets. While they failed to reach their 100 horsepower upgrade goal, in the later stages of the test, they found that the engine was able to safely output 700 horsepower. In order for the vehicle to survive for 24 hours, the engineers reduced the engine output to 650bhp, and capped engine rpm at 8, 500 rpm. According to the team's engineer, if engine durability was disregarded and the rpm limited removed the R26B could produce 930 horsepower at 10, 500rpm.
However, how could they make the 787B go seven seconds faster for each lap reliably? To find out, Mazda recruited Belgian racer Jacky Ickx , a six-time 24 Hour Le Mans champion, as their team consultant. Under his recommendation, the automaker partnered with the French Oreca team, as they prepared for the WSC European races, which also included the 24 Hours Le Mans. Ickx recommended Oreca because they provided trusted support for his Paris – Dakar victory. Prior to Le Mans, Oreca tested the 787B at the Paul Ricard circuit in France, and even before that, it managed to finish ninth at the Monza WSC round.
Mazda arrived at the 1991 24 Hours Le Mans with two 787Bs, as well as the older Japanese model 787 as backup. According to new race rules, the Mazda 787B / 787, Jaguar XJR-12 and Mercedes C11 were entered under old Group C rules, so they all belonged to Group C2. The new prototypes which used the 3.5-liter naturally aspirated engine such as the Peugeot 905, Mercedes C291, Jaguar XJR-14 and the Spice SE89C (a private car team model which was fitted with the Ford- Cosworth DFZ V8) belonged to Group C1. In order to compensate for the speed advantage of the faster C1 cars over the C2 cars, the C2 cars were gridded in the first ten grid spots. This is why, the number 6 car, which was Spice SE89C, despite finishing 39th in qualifying, started from the tenth position. On the other hand, the the number 3 Mercedes C11 car, in the hands of the emerging Michael Schumacher, was the fastest qualifier, but was gridded eleventh for the start. As a result, Mazda’s strongest 787B driver lineup of Volker Weidler, Johnny Herbert and Bertrand Gachot, in the number 55 car, was moved back from twelfth to nineteenth.
During the qualifying, the Mazda team had already discovered that the 787B was lapping five seconds faster than the 787, but in order to achieve better fuel consumption, Jacky Ickx instructed the drivers to concentrate on being smooth during acceleration and braking. To assist them, the cars were fitted with a bespoke fuel efficiency gauge so they could tailor their throttle applications to make full use of the engine's 95% maximum torque between 6, 000 to 9, 000 rpm while also achieving the fuel consumption target of 1.85 miles per one liter of petrol. Volker Weidler was best at interpreting Mazda’s tactic due to his rich experience with rotary race cars. He was even able to surpass the speeds of Yojiro Terada, who was known as Mazda's “Mr. Le Mans”. The team even arranged Weidler to tutor teammates Johnny Herbert, Bertrand Gachot and Stefan Johansson.
Mazda was able to be the first Japanese automaker to win 24 Hours Le Mans, because of their successful mathematical tactic. It should also be noted that the victory was due to the fortunate timing and good luck, since neither Toyota or Nissan participated in the 1991 tournament. During the race, the Jaguar XJR-12, which used a 7.4-liter V12-powered engine was forced to
reduce its speed to control fuel consumption, and both the Mercedes C11 and Peugeot 905 cars, which were much faster than the 787B, experienced accidents, mechanical failures and even a small fire. Indeed, while it sat during a pitstop, the winning 787B was able to “pass” the initial leader, the Mercedes C11, in the last two hours when the C11 experienced a mechanical failure and was forced to withdraw. Such is endurance racing.
In comparison, the 787B number 55 car, had a much smoother race. There were no major failures, and its use of the lighter graphite brake discs allowed the car to obtain quicker acceleration and braking responses. In order to properly control the temperature of the brake system, the engineers redesigned the suspension geometry. Expanding the rim diameter from the original size of 17-inch to 18-inch allowed better heat dissipation. During the race, the car only had a front brake disc replacement, and replaced just three front brake pads and one rear brake pad. Without the need to change the rear brake discs, as they lasted the entire 24 hours, time lost during pitstops were significantly reduced.
The number 55 Mazda 787B crossed the finish line with a two lap lead over the runner-up Jaguar XJR-12. Since the lead change of the race happened so unexpectedly, Technical Director Hiroki Namura, decided to change their tactics after discussing with Jacky Ickx. Johnny Herbert, who was most familiar with the track, was left in the car to finish the final three stints (each being 45 minutes long). According to Herbert, who lost 2kg during the race, his drinking water had already depleted during first stint out of the last three. With the sunny afternoon, the cockpit temperature was particularly high. As he returned to the pit after crossing the finish line, he fainted due to dehydration, and was immediately taken to the medical unit for treatment. Even though he made it to the post-race celebration party, he missed the Le Mans podium, which would have been his most glorious moment of the race.
Had Mazda been able to choose, perhaps they would have rather had car number 18 take the victory. After all, that car was painted in blue and white, Mazda’s corporate colours. On the other hand, car number 55 was sponsored by the Japanese clothing company RENOWN, so it was painted in orange and green instead.
The Mazda team traveled directly from their triumph at Le Mans to Mazda’s Hiroshima headquarters and were welcomed like heroes at the airport. The automaker initially prepared for a victory parade in the center of the city, but decided to cancel the festivities. Mazda was in the
midst of wrestling with the United States over the bilateral trade rules, and the company was deeply concerned about how their celebration would be viewed by Americans who were already wary about the Japanese automakers' massive output of quality, yet inexpensive automobiles. After all, the Mazda showrooms in America were once destroyed by anti-Japanese Americans.
After the winning 787B was shipped back to Japan, the engineers at Mazdaspeed took the car engine apart, and carefully examined each part in front of the Japanese media. They concluded that the condition of the R26B engine showed it would still able to cope with another 24 hour race without any maintenance.
By 1992, the rules of the Group C match completely changed, and Mazda could no longer compete with their rotary engines. In order to continue to participate in the WSC championship and return to the Le Mans to defend their title, Mazda had to develop a new car, the MXR-01. Since the new car had to use a 3.5-liter V10 engine, its power system was completely different from the previous winning R26B. To minimise their costs, Mazda decided to directly purchase the GV10 F1 engines from the British racing engine manufacturer, Judd. After they further improved it, they renamed it the MV 10. They also acquired the Jaguar XJR-14 chassis from Tom Walkinshaw Racing, who was in the process of exiting the WSC. At the 1992 Le Mans, Mazda sent over two MXR-01 cars; one which finished fourth, with the other a DNF. This was the final chapter for Group C prototypes, and with the end of the Group C era, Mazda's glorious achievement officially became history.
In the end, Mazda's fabulous victory became an eternal legend in Japanese motor racing history. The winning 787B (No. 787B-002) is still displayed inside of the museum at the Mazda factory in Hiroshima. The ACO (Automobile Club de l'Ouest), the official organiser of the 24 Hours Le Mans, has chosen the 787B as a 90's classic for the race, a replica of the 787B is also permanently exhibited in the museum in Le Mans.
Over the years, many loyal fans have been asking when Mazda will return to endurance races. As Nobuhiro Yamamoto says, the automaker has always been looking for an opportunity to return to the Le Mans. At the end of 2012, during the annual Mazda Festival at the Okayama track, the automaker even announced that it will enter the WEC (World Endurance Championship) as an engine supplier. They will compete in the 24 Hours Le Mans, providing private teams in the LMP2 category with 2.2-liter SKYACTIV-D diesel engines. Unfortunately, Mazda had to cancel their plans when the race rules changed, and the FIA prohibited diesel engines from taking part in LMP2 class.
Yet, in another perspective, Mazda had indeed returned to in 2011. Twenty years after their victory, Mazda brought back their 787B as a demonstration vehicle at Le Mans. On board was race winner, Johnny Herbert. At the Goodwood Festival of Speed last year, there was also a 787B on track, demonstrated by 7-time MOTO GP champion, Valentino Rossi. Luckily for Mazda, the car which crashed at Goodwood last year was a 767B, not a 787B.
TEXT | SOBE CHOW, JOYCE TSANG
PHOTOS | KIMIO NG, MAZDA MEDIA