Among the most famous wins in motorsports history is Mazda's->ke53 1991 win at the 24 Hours of Le Mans. The 1991 Mazda 787B racecar claimed the first, and still only win for a Japanese manufacturer at Le Mans->ke1591, as well as the only win from a car with a rotary engine. But there was another car that paved the way for the 787B, another rotary-engined car that won a 24-hour endurance race a full decade before Mazda's win at Le Mans, and that car is an RX-7->ke344 belonging to Tom Walkinshaw Racing.

In 1981, the RX-7 was still a pretty new car, having only just debuted in 1979. It wasn't completely new to motorsports, and had even grabbed a class win at the 1979 24 Hours of Daytona, similar to the kind of success enjoyed by earlier Mazda rotary racing cars. But in 1980, Mazda and Tom Walkinshaw entered the 24 Hours of Spa Francorchamps. It wasn't an impressive year for the RX-7s at Spa, but the lessons learned were put to good use, and in 1981, TWR grabbed an overall win at Spa, finally providing really solid evidence of the performance potential of the Wankel rotary engine.

Continue reading to learn more about the 1981 Mazda RX-7 TWR Race Car.

Exterior

From the outside, the TWR RX-7 looks a lot like the road-going version of the car. Spa is, after all, a GT3 event, and all of the cars participating are based heavily on street machines. Like the road car, the RX-7 is smaller than you'd probably expect, and this is true for all generations of the car. That's because Japanese tax regulations for cars go off not only engine displacement but also the overall dimensions of the car. Since the RX-7's small engine displacement qualified it for the small vehicle class, Mazda was sure to make it fit the sizing regulations as well. This helped the car a lot in Japan->ke138, since it meant much lower taxes on the RX-7 than on competing sports cars.

Interior

Technically, there is an inside part of this car, but it isn't exactly what you'd call an interior. This is a race car, so anything that wasn't absolutely necessary for going fast was stripped out. As for the road-going version of the first-gen RX-7, the interior was nice enough for a car from the late '70s. And if the previous sentence made you think about velour upholstery then you're thinking along the right lines. It is surprisingly roomy for such a small car, but it's the automotive equivalent of a sardine can compared to what a lot of other manufacturers were putting out in 1979.

Drivetrain

The 1981 RX-7 had a 1.1-liter Wankel twin-rotor engine. This put out 105 horsepower originally, but was bumped up to 115 horsepower for 1981. In racing form, the engine made 225 horsepower, and this created a problem for racing officials. Since the rotary was able to produce far more power than any of the piston engines with a similar displacement, the RX-7 had to be run in a higher class, with cars that had 2.5-liter engines. Not that this ended up mattering much, since the RX-7 took an overall win anyway. There were some other advantages to having such a small engine that racing officials didn't have a way to counteract. The main one was that the engine could be mounted much further back, making this a front-mid engine layout, which worked out better for balance and handling. The car was also incredibly light, even in road-going form, and this more than made up for the power disadvantage it had in comparison to the other cars in the race.

Competition

Ford Capri

The Capri->ke3126 was dreamed up by Ford as a relative of the Ford Mustang->ke428, but for the European market. It had similar styling but was smaller and offered a wider variety of smaller engines, though V-8s were available at points. There was no V-8 for 1981 though, and Ford went racing with a 3.0-liter V-6 in the Capri. It won Spa for three consecutive years before Mazda's win. It was a very capable car and Ford->ke31 sold them in huge numbers.

BMW E28 5 Series

New for 1981, the E28 was a big success for BMW->ke178, especially when it came to motorsports, and it would be this generation of the 5 Series that would give birth to the M5->ke2922. That wouldn't be until a few years after it was introduced though, and at first BMW would go racing with the 528i. This is the car that won Spa in 1982, giving BMW the experience to dominate the race for most of the rest of the '80s, first with the 635 CSi and then the M3.

Conclusion

This car and its 1981 Spa victory are two very important items on the long list of reasons why RX-7 fans love these cars so much. In beating so many established motorsports heavyweights, Mazda finally showed that there really was something to rotary technology. The RX-7 would go on to become an even more amazing machine, and so would Mazda's rotary flagship, the 1967 - 1972 Mazda Cosmo. It's a little-known piece of history that was hugely important for this particular niche.