Frankfurt: Mazda MX-5 Superlight

You’ve probably seen and read a bit about the Mazda MX-5 Superlight by now. If so, you’ve seen enough to know that, in pure performance terms, this car is a having bit of a laugh. It has bugger all power and as a result it’s quite slow. There’s a meagre 93kW on offer and that’s just enough to break 9 seconds for the 0-100 sprint.

Thing is, though, I reckon it is one of the best cars revealed at the Frankfurt Motor Show. Simply because I think it looks so damn cool. The long bonnet, the bespoke interior details (what’s left of it) and the rollover hoops complete a look that is pure sportscar.

I like the fact Mazda’s engineers have gone about producing a car with a sole focus. That they have looked at the overall car and taken the approach of removing stuff first, then thinking about what actually needs to be put back in.

“I’ve dreamed of building a Mazda MX-5 with this kind of radical form for a long time,” says Peter Birtwhistle, Mazda Motor Europe’s Chief Designer, referring to the project. “Now that weight reduction has become a dominant factor in automotive development, the time is ripe for it. We show how lightweight a car today can be.”

But, its not all beer and skittles. I am quite puzzled as to why the show car’s power has dropped by 22% from the 118kW that you get from an entry level MX-5. Also, the reality is that the Superlight’s strict weight loss program has only saved 134kg compared the soft top road car.

Lucky it looks so good. There’s a long press release from Mazda below along with a comprehensive photo gallery.

MX-5 Superlight version—Less is More

The world of automobiles and individual mobility is moving towards energy efficiency, environmental compatibility and uncompromised safety – along with dynamic attributes and driving fun. In its efforts to offer pure driving enjoyment, while meeting its ecological and social responsibilities, Mazda has been focusing on weight reduction as a core base technology. For 20 years, reducing weight has been a tradition with the MX-5. It provided the inspiration for the radical design of Mazda’s latest show car and its radical interpretation of the cult roadster.

This year Mazda celebrates the 20th anniversary of the first MX-5 roadster, which laid the cornerstone for its Zoom-Zoom brand philosophy – reason enough for Mazda designers to create a fully-drivable show car, the MX-5 Superlight version. There are no plans to build this car, but it demonstrates how individual mobility can be maintained in a way that uses fewer natural resources.

Mazda’s European R+D centre in Oberursel has created a show car that represents the essence of Mazda’s fun-to-drive aspect. Based on the brand icon Mazda MX-5 Roadster, the MX-5 Superlight version is a pure, uncompromising two-seat sports car meant to be affordable to just about anyone. The main challenge for the design team in creating this roadster was “to evolve the MX-5, developed to perfection during the last 20 years, to a higher and extreme level,” says Project Lead Designer Hasip Girgin. The result of their efforts is a roadster show car with an exciting design that is especially lightweight and distilled down to the very basics of sporty driving, that still manages to provide modern safety technologies. In an increasingly digitalized world, it creates a linear, direct bond between man and machine. Its conceptual purity means even better driving dynamics and fuel efficiency, which is accomplished by keeping the vehicle below the 1000 kg threshold. As a show car for lightweight construction and driving enjoyment, the MX-5 Superlight version is the ideal ambassador for Mazda’s brand values.

Exterior Design
“I’ve dreamed of building a Mazda MX-5 with this kind of radical form for a long time,” says Peter Birtwhistle, Mazda Motor Europe’s Chief Designer, referring to the project. “Now that weight reduction has become a dominant factor in automotive development, the time is ripe for it. We show how lightweight a car today can be.”

His design team reduced the MX-5 down to its core attributes to create a pure roadster. Development of the production model MX-5 focussed on the bond between driver and co-pilot to the roadster, the car’s driving dynamics and its open-top experience. The goal of the MX-5 Superlight version concept was to strengthen these bonds even further. By doing this without a windshield, the retractable top and its frame, designers achieved an important step in this direction. As the concept MX-5 Superlight version, the allweather production roadster has mutated into a driving machine that lets sports car enthusiasts enjoy the natural surroundings unfiltered and tangible. Not only does the wind blow unimpeded during driving, pilot and co-pilot can also experience the sounds, smells and temperature changes of their immediate surroundings. And finally, the show car’s intense bond between the driver and the technology of the vehicle gives it a unique closeness that can only be found in stronger form in the cockpit of a race car.

Mazda designers created special roll-over bars, not only because they are very sporty-looking, but also to contribute to aerodynamic efficiency. These also make it clear that roll-over protection is important in this concept. And they prevent wind turbulence around the heads of the passengers, from whom the law would require the wearing of helmets while driving.

By removing equipment not vital to driving, and by replacing vital things with components that support the unique concept of the vehicle, designers sharpened the character of the MX-5 Superlight version.

Because there is no windshield, for instance, there is obviously no need for wipers. The roadster show car’s completely open design makes the need for outer door handles, side windows and their openers unnecessary. A single, filigree aluminium, wide-angle mirror gives a good view of the road behind. It’s placed inside an extension of the bonnet. Front and rear lights are the same as those of the production model with additional LED lamps at the front, and brake lights at the back of each roll-over bar, which contribute to the roadster’s sporty look.

The lack of a windshield required an extension of the original aluminium bonnet into the cabin. The attached sheet here is made of lightweight carbon fibre and provides a hood for the dashboard frame.

This also changed the proportions of the body’s design, making the front of the car longer and the passengers seem like they are sitting further back towards the rear-drive axle, all of which is enhanced by the massive roll-over bars and their aerodynamic cladding. The MX-5 Superlight version translates the dramatic proportions of historical race cars into a very modern form.

Interior Design
The purity in design of the exterior also characterizes the interior design, which does not have aesthetics as ultimate goal, but was conceived to contribute to reducing vehicle weight. Driver and passenger of the MX-5 Superlight version are greeted by racing bucket seats made of ultra-lightweight carbon fibre. They are slide adjustable and upholstered with the same saddle coloured leather as the armrests, the steering wheel, and the lightweight aluminium shift lever and hand brake. Colour-coordinated four-point seatbelts hold the driver and passenger firmly in their seats.

The bonnet extension into the passenger cell provides a canopy for the dashboard, which makes the dashboard look smaller than the production MX-5. Made of lightweight plastic reinforced with fibreglass, it contains the same instruments as the production MX-5. These are held in place by a dashboard frame made of lightweight carbon fibre. Like a purebred race car, the MX-5 Superlight version has an ignition button in the centre of the dashboard, along with two emergency kill buttons for immediate fuel and electricity cut-off.

Supplying air and climate control to the open passenger compartment is only possible in limited form, so the show car has no air conditioning and no fans. Air-flow is increased when the roadster accelerates, and only small air vents are needed. The interior is made without any trim. Sound insulation mats and rugs do not meet the requirements of a purist roadster like this and are not used at all.

Also made of ultra-lightweight carbon fibre is the “floating-design” centre console with iPod® adaptor and the triangular reinforcements in the trimless doors. Driver and passenger can rest their arms here while driving.

Driving Dynamics
The Mazda MX-5 Superlight version show car is fully-drivable, but there are no plans to produce it in the near future. Under the bonnet is the cultivated and frugal MZR 1.8-litre four-cylinder engine paired to the production roadster’s five-speed manual transmission. It develops 93 kW/126 PS of maximum power at 6,500 rpm. For an appealing engine sound, there’s a Mazdaspeed cold-air intake made of polished and powder-coated aluminium and a Mazdaspeed exhaust system, both of them specific to the MX-5 Superlight version. These systems deliver more intake air-flow, and less exhaust-gas back pressure.

The engine sound is designed to suggest an engine with much higher displacement than the concept actually has. During charge cycles, a high-resonance bubbling sound in the muffler delivers the exciting sporty sound you expect from a very powerful engine.

The show car is designed to provide improved driving dynamics as well, and uses a four-piston, fixedcalliper brake system with perforated discs that, because of their size required an increase in track of 50 mm. A specially tuned chassis with a Bilstein® B16 coil-over suspension and Eibach® stabilisers give the body of the MX-5 Superlight version a ground clearance that is 30 mm lower than the production MX-5. Its sporty hydraulic power-assisted rack and pinion steering system is the same as that of the regular roadster. Its linear steering, coupled to a precise-shifting five-speed manual transmission with short shift travel, have contributed to the character of the world’s most successful roadster for years.

Also from the production model are the roadster’s 205/45 R17 original-equipment tyres and alloy wheels from the 2.0-litre version, which are some of the lightest on the market today at less than 8 kg.

Specifications – Mazda MX-5 Superlight version

• Body Type: Roadster Monocoque
• Seating capacity: 2

External Dimensions

• Overall length: 4,020mm
• Overall width: 1,720mm
• Overall height (unloaded): 1,110mm
• Wheelbase: 2,330mm
• Track (front/rear): 1,540/1,545mm
• Ground clearance: 106mm

Engine & chassis

• MZR 1.8-litre petrol
• Max. power: 93kW/126PS at 6,500 rpm
• Max. torque: 67Nm at 4,500 rpm
• Transmission: 5-speed manual
• Front/rear suspension: Double wishbone/Multi-link
• Damper (front/rear): Bilstein® monotube
• Tyre size: 205/45 R17
• Brake type (front/rear): Ventilated discs/Solid discs
• Brake diameter (front/rear): 300/280mm

Performance

• Acceleration 0-100 km/h: 8,9 seconds*
• Fuel consumption (combined): 6,3l/100km*
• CO2 emissions (combined): 150g/km*
• Min. kerb weight (without driver): 995kg

* Show car target value

Building the Show Car

The task sounded challenging and time was short. After the decision was made to present a radical Mazda MX-5 Superlight version show car at the IAA in 2009, Peter Birtwhistle had only three months to complete it. He quickly formed a five-person team – including Hasip Girgin, Luca Zollino, Nigel Ratcliffe, Maria Greger und Luciana Silvares – which began by designing the cockpit.

There was not enough time for small-scale modelling. The designers put their ideas to paper, decided which were best, then modelled these directly onto a full-scale clay model. The cockpit was created together with the interior door braces. All components were then digitalized. This data was sent to an external studio for prototype build, where the parts of fibreglass-reinforced plastic and carbon fibre were made and later fitted. This method was also used to create the centre console with gear shift lever and hand brake.

Parallel to this, a production MX-5 Roadster with an MZR 1.8-litre powertrain was stripped of all components that would later be replaced.

Under the leadership of Mazda’s design team and chassis engineers, a drivable “blank” of the MX-5 Superlight version was created that weighed well under 1,000 kg, while respecting the original roadster’s ideal 50/50 weight distribution. Mazda test drivers then drove the roadster around a closed track with experts from Bilstein® and Eibach®, in order to ascertain the feasibility of the project.

The results amazed even the most experienced engineers: with hardly any re-working, the “light” MX-5 version was an easy-to-control, safe-driving roadster that displayed agility, great driving dynamics and acoustical appeal.

Final assembly began with painting the body in white colour, and simply polishing the original MX-5 aluminium bonnet. Then the racing seats, steering wheel, gear shift lever and hand brake were upholstered in leather and installed in the show car. This was followed by the installation of all previously-built carbon fibre components. And at the end, Mazda designers installed the centre console, the dashboard and instruments, seatbelts and roll-over bars.

Weight Saving Measures in Detail
Less is more! This was the formal process that Mazda designers followed when building the MX-5 Lightweight version at Mazda R+D studios in Oberursel, Germany. All components that were not absolutely required for driving were put on the scales. Safety components were left untouched. Weight savings, by either elimination or replacement, were undertaken on the following components:

• Windshield with frame and wipers
• Retractable soft top and folding frame
• Side windows including window openers
• Outer door handles and side mirrors
• Audio system
• Interior trim, rugs and sound insulation
• Production-model seats
• Air conditioning system, heat exchanger and ventilation system
• Dashboard frame
• Centre console
• Gear shift lever
• Hand brake lever
• Armrest between the seats

History of Mazda MX-5 Concept Cars
The MX-5 has benefited from different concept cars throughout its 20 years history. In 2000, Mazda’s American design studio created the Miata Mono-Posto Concept for the SEMA show. An earlier step in the direction of a more radical MX-5 was taken by Mazdaspeed in Japan, which created the Roadster MPS Concept in 2001. This idea was reinterpreted in 2004 with the Mazda Roadster Coupe TS Concept, which had a classic Italian coupe shape based on the roadster.

And finally, in 2003 the design study Mazda Ibuki was built that hinted at the third-generation MX-5, which was launched two years later. Not only did Mazda Ibuki have extremely small overhangs and the more austere design language of the later production model, it also anticipated some major conceptual changes. For instance, the drive assembly of the concept was positioned lower and further toward the middle of the vehicle, for a lower centre of gravity and an equal weight distribution over both axles. The production car that appeared later would boast an ideal 50:50 weight distribution front and rear, and deliver excellent handling attributes.