#Focus – The Four Rotor Mazda 767B-003.

The first time Mazda used a four rotor engine in one of their sports prototype racers at Le Mans was in 1988 and this was achieved through the introduction of the almighty Mazda 767 and introduction of the 13J-M2 Wankel rotary unit.

But back to history, Mazda was no stranger to Le Mans or to motor sport with the Wankel rotary engine. Talking about the Le Mans 24 Hours, the first taste of the rotary sound was given back in 1970 with the Belgian and Levis International Racing Team entry of Yves Deprez and Julien Vernaeve through the use of a Chevron B16 and Mazda 10A two rotor equipped car. They failed to finish but they did set the benchmark.

Then came the Sigma MC74 equipped with the 12A two rotor engine and which scored the first ever finish for a rotary engine at Le Mans. Dead last, not even classified but it was the first time a full Japanese entry completed the 24 Hours. And this was followed in the 1980s with a couple of entries through the IMSA GTX class and the RX7. Mazda then decided it was time to get serious about the idea of Wankels at Le Mans and started the path in the prototype class with the 717C from 1983 and which took a 1-2 finish in the C2 class that same year at Le Mans.

From 1986, Mazda decided to jump for the IMSA GTP category which differed from the Group C by allowing fewer restrictions and Nigel Stroud was tasked with the build of a complete new car which resulted in the 757 model equipped with the three rotor unit for 1986 and 1987.

From then and for 1988, Stroud was tasked with the build of an even more competitive car. This entirely in-house creation was to be called the 767. The new model, apart from being far more advanced in terms of chassis and aerodynamics, introduced the first four-rotor Wankel rotary engine used by Mazda in competition. Displacing just 2.6 liters, the normally aspirated unit produced 580 hp in 1988 specification. The 767 was brought alongside two Mazda 757s with three rotor units, with the increased power output of 580 hp and thus 130 hp stronger than the units used in the older cars the new engine proved to be very reliable, however the 767 only became third of the Mazdas at Le Mans due to a higher fuel consumption.

Therefore Mazda endeavored to improve new engine for the following year. By adjusting the admission chambers and using ceramic tips for less wear and improved sealing, Mazda not only reduced the fuel consumption, but also again increased the power of the engine by 50 hp, which meant a total output for the 1989 season of 630 hp.

More globally speaking, the 767 would be updated into the 767B for the 1989 season, now sporting the more powerful engine unit among additional improvements in aerodynamics and architecture. The Mazda 767B known as chassis 003, is one of three cars built by Mazdaspeed for 1989.  According to entry listings for the 1989 24 Hours of Le Mans, 003 was entered as No. 203 and was driven by Yojiro Terada, Marc Duez, and Volker Weidler. The trio would bring the Mazda to a respectable third in the GTP class and 12th  overall. The Fuji 1000 Km would be the next outing for 003, where it scored a eleventh place finish overall and second in the GTP class.

For 1990 it received a new cooling system, a trellis mounted wing above the gearbox, a more rigid chassis with unchanged dimensions and a new bodywork with a shortened and more rounded rear. After almost two decades of development work Mazda finally reached the point of definitive competitiveness in endurance racing witch their rotary racing machines.

In 1990 Mazda continued it’s habit and brought two newly developed 787s, with the ultimate version of their four rotor engine called 26B, alongside one 767B in it’s final development phase to La Sarthe. Since both 787s failed to finish the sole 767B known as 767-003 came in 20th overall and first in the IMSA GTP class.  The final race for 003 as a factory Mazda entrant was another trip to Fuji for the 1000 Km, where it would place sixth overall and win the GTP class for the second race in a row.

And of course, the path was set for 1991 and the Mazda 787B R26B engine to conquer the Le Mans 24 Hours and set what still remains up to this day, the sole victory for a Japanese manufacturer and a Wankel rotary engine at La Sarthe.


The car, as raced during the 2014 Spa-Classic event in Spa-Francorchamps, Belgium by the Werner brothers.

And it’s up for sale here – Gooding & Company

 

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