FULL THROTTLE TOWARDS THE FUTURE

THE ROTARY ENGINE REIMAGINED

Innovative, smooth-running, challenging – the possibilities and limitations of the rotary engine have always fascinated the automotive industry. What better brand to make them a success than Mazda? With a past full of envelope-pushing rotary models under their belt, Mazda now takes the technology in a bold new direction. With the Mazda MX-30 R-EV, the first-ever PHEV with a rotary engine power generator.

‘A new era’, ‘the powertrain of the future’: These are some of the ways in which the trade media expressed their initial euphoria over the German invention of the Wankel engine. Incidentally, they could just as well be used to describe the latest innovation in rotary technology, the Mazda MX-30 R-EV. Premiered in 2023, the model marks the first return of this engine type to the brand’s production cars in eight years. In the form of a power generator, a 50l fuel tank recharges the battery of this PHEV while driving, extending the range to up to 680 kilometres without the need to charge or refuel. This latest breakthrough, however, is only the latest instalment in a decades-long history between Mazda and rotary engines – an infatuation that dates back as far as 1961.

On 4 July of that year, the Japanese government officially approved Mazda’s licensing agreement with Germany’s NSU Wankel GmbH regarding the use of the revolutionary rotary engine. Designed by inventor Felix Wankel, the engine requires neither pistons nor cylinders.

Instead, rotating discs replace the up-and-down motion of the pistons, resulting in low-vibration operation, minimal noise emissions, a space-saving design and reduced weight. This technological breakthrough prompted Mazda engineers to completely rethink the automobile. Not just to bring the rotary engine to production maturity, but also to develop ground-breaking vehicle designs in which the powertrain’s advantages could truly shineInstead, rotating discs replace the up-and-down motion of the pistons, resulting in low-vibration operation, minimal noise emissions, a space-saving design and reduced weight. This technological breakthrough prompted Mazda engineers to completely rethink the automobile. Not just to bring the rotary engine to production maturity, but also to develop ground-breaking vehicle designs in which the powertrain’s advantages could truly shine.

CHAL­LEN­GER SPI­RIT – MAZDA RE­INVENTS THE RO­TA­RY EN­GI­NE

 

Although ultimately it was the rotary engine models that first earned Mazda worldwide brand recognition, the road to get there was not an easy one. Rotary engines come with their own unique challenges, and the hurdles posed by the new technology caused almost all of the 30 or so other licensees to give up on the engine. 

Not so Mazda. At the 1964 Tokyo Motor Show, the company presented the futuristic Cosmo Sport 110 S, a prototype developed by the ‘Mazda Rotary Engine Research Department’. This research centre was headed by chief engineer (and later Mazda president) Kenichi Yamamoto who, within just two years and with a team of 47 engineers, optimised the production quality of the engine materials and made the engines themselves durable. 

Looking back, Yamamoto recalled, “Our team of engineers and technicians rose to the challenge with tireless effort, determination, and a fighting spirit.” The bold drive technology was paired with daring vehicle design and a dedication to Japanese aesthetics and craftsmanship that already expressed Mazda’s ‘Crafted in Japan’ mentality.  With an exceptional design, inspired by famous Italian sports car, the sleek two-seater stood at just 1.17 metres tall and was soon likened to an aerodynamic ‘Superbird’.

 

1967 MAZDA COS­MO SPORT 110 S


The Mazda Cosmo Sport 110 S went into production in May 1967 as the world’s first vehicle with a twin-disc rotary engine. Tsuneji Matsuda gave a vivid description of the driving experience in the racer: “It’s more like flying than driving a car.” From the outset, this rotary engine pioneer also featured impressive endurance: The Cosmo Sport 110 S secured a respectable fourth place in its very first race, the 84-hour Marathon de la Route at the Nürburgring. It was to be a prelude to over 200 victories for Mazda with rotary engines in touring car racing series – and, at the 14th attempt, a triumph in the most famous of all 24-hour races: Le Mans. In June 1991, it was the Mazda 787B, powered by a four-disc rotary engine, that outclassed the assembled competition from Mercedes, Jaguar, and Porsche, claiming the first overall victory for a Japanese team.

FROM THE RACE­TRACK TO MASS PRO­DUC­TI­ON

 

These initial forays into motorsport bolstered Mazda’s global profile and boosted sales of its production models. The pioneering Cosmo Sport 110 S was followed by 34 more rotary models, including such brand icons as the Gran Turismo Luce R130, Mazda Parkway, and RX-7. In the early 1970s, every second Mazda had a rotary engine under the bonnet. Coupés were the most common, but the brand also produced rotary sedan and station wagon models, as well as a rotary pickup. The height of rotary culture, however, took a hit during the first oil price crisis in 1974. Although Mazda rotary models served as benchmarks when it came to meeting strict emissions regulations, their fuel consumption figures still tended to be higher than those of conventionally powered competitor models.

To counter the sudden plummeting of sales figures, Mazda launched the ‘Phoenix’ project in 1974 under the leadership of Kenichi Yamamoto. The seemingly impossible became reality: Thanks to technical modifications, the fuel consumption of rotary models was reduced by 50 percent, as demonstrated by the Mazda RX-7, a Japanese style icon introduced in 1978 and running until 2003. In the 1990s, Mazda also showed what the rotary engine could do in the ultra-luxurious Gran Turismo segment, releasing the first serially produced three-disc rotary engine in the Eunos Cosmo. The last Mazda production car to feature a rotary engine was the RX-8, which was produced from 2003 to 2012  and reached a breath-taking revving ability up to 9,000 rpm. Characteristics that earned the model the prestigious ‘International Engine of the Year’ award.

A RO­TA­RY FU­TURE OF SUSTAI­NA­BI­LI­TY

Though ground-breaking in different ways, all Mazda rotary models share the almost perfect mechanical smoothness typical of this engine type. This driving pleasure is one of the reasons Mazda is looking towards rotary engines to once again power their production cars – as is their potential for cutting-edge sustainability. As early as 1991, Mazda demonstrated that the rotary engine is suitable for emission-free operation with hydrogen or battery electric drive technology. The concept of a rotary range extender was already introduced in 1970, and has finally been realised in the full-production electrically powered Mazda MX-30 R-EV. Unlike with any other PHEV, the model’s rotary ICE is not used to drive the wheels, but rather generates power to charge the electric battery. This makes for a uniquely electrified driving experience, sacrificing none of the joy of driving so essential to the band. As an important puzzle piece for Mazda’s multi-solution approach to powertrains, the MX-30 R-EV breathes new life into the rotary engine success story spanning more than 60 years. 

RO­TA­RY TH­ROUGH HISTO­RY: FA­MOUS MAZDA MO­DELS

1967. Cosmo Sport 110 S Mazda’s first dual-disc rotary engine production model delivered only 81 kW/110 hp, but could already reach 200 km/h in tests
1969. Luce R130 Coupé The Gran Turismo model marked Mazda’s entry into the luxury segment
1970. RX500 Concept car with a radically angular and streamlined design
1974. Parkway The first 26-seater rotary coach with rotary engine, the model is still beloved by Mazda fans today
1975. Roadpacer AP 

Exclusively sold in Japan, this statesmanlike limousine was aimed at government and industry higher-ups
1978. RX-7 The most-built rotary model of all time within its first generation, with exactly 471,018 units produced (more than 800,000 across three generations)
1990. Eunos Cosmo The first serially produced three-disc rotary engine
2003. RX-8 Following the widely successful RX-7, the model featured a revolutionary design with no B-pillars and was equipped with a newly developed, lightweight and efficient RENESIS two-disc rotary engine
2015. RX-Vision Celebrated as the `Most Beautiful Concept Car of the Year’ in 2016, this sports car concept featuring a Skyactiv R engine hailed the beginning of the Kodo design philosophy