In our first blog on the cute and cool Mazda MX-5, we examined the design and development that went into creating the prototype. Once the decision to put a world-changing sports car into production had been made and the basic design concept had ended up becoming public knowledge (to some extent at least), Mazda had to do the difficult part; develop a car that didn’t quite fit into the corporate plan.
That one running prototype that had caused such a sensation on the roads of Santa Barbara in California, V-705, had been built in the UK by IAD.
IAD had effectively, and quite logically, copied the construction and layout of what some would argue was the greatest roadster ever made, the Lotus Elan. Thus, it featured a bespoke backbone chassis and fibreglass body, with RX-7 Mk1 front suspension, the rear suspension of a 929 and the 1.4-litre OHC engine and gearbox from a 323.
The V-705 prototype is in testing.
IAD had effectively, and quite logically, copied the construction and layout of what some would argue was the greatest roadster ever made, the Lotus Elan. Thus, it featured a bespoke backbone chassis and fibreglass body, with RX-7 Mk1 front suspension, the rear suspension of a 929 and the 1.4-litre OHC engine and gearbox from a 323.
Lotus Elans in production at Hethel, Norfolk, in the early 1970s.
The influence of the Elan was key to the first MX-5’s development and affected nearly every area, from styling to structure and driving dynamics, but it shouldn’t be overstated because they were very different cars. For all its handling poise, beauty and sheer magnetism, the car made famous as Emma Peel’s wheels were created 27 years earlier to sell at a different price point in a different market segment. It was also designed to be almost hand-built in relatively tiny numbers. Amazingly, it was only Lotus’ second-ever proper road car, the 1957 Elite being the first. It was a huge success for the fledgling Lotus company with over 12,000 being produced between 1962 and 1973. That success gave Lotus the income it needed to open a new factory in Norfolk and expand rapidly. Mazda, on the other hand, would be defining the success of the MX-5 by very different parameters. The company commenced the MX-5’s development expecting to make the volume Lotus had made in 11 years in a matter of months and needed to design a car that met modern safety legislation and was as reliable as a Mazda hatchback. Mazda was, effectively, aiming to produce a new MGB with the Elan’s dynamics and that, many would argue, is the perfect attainable sportscar.
MG produced well over half a million MGBs in 18 years of production from 1962, making it the best-selling sports car of all time at that time.
Mazda produced their millionth MX-5 in 2017 but were by then on their fourth all-new version of the car.
The styling and experimental phase of the new car was frozen in late October 1985 and so 1986 was an important year in the life of project P729, as it had now become known. Toshihiko Hirai was made Product Programme Manager after volunteering to switch from his role on the 323 and he was assisted by two planners, Kazayuki Mitate and Hideaki Tanaka. They knew the car would have to be a steel monocoque to meet the volume and crashworthiness required and a structure was engineered that would prove rigid enough to justify the car being fitted with double wishbone suspension, which gives a better handling/ride compromise but only works properly when mounted to a rigid structure. Modern computer-aided design meant this structure was also lighter than previous monocoque convertibles. This was a double win and was aided by a nod to the Lotus Elan’s backbone chassis as the engineers developed the power plant frame or PPF. The PPF was a frame which ran along the side of the prop shaft, eliminating the axle tramp quite common on older sports cars by stiffening the link between the gearbox and driven axle.
Mazda’s North American styling team, led by Tom Matano, started working on a third full-size clay model which got quite close to the final style. That was worked on by Mazda’s Chief Designer Shunji Tanaka in Hiroshima who set about trimming what he saw as excess flab from the design. He ruthlessly skimmed 35mm off the top of the scuttle and 13mm from the wheelbase, which involved moving the battery to the boot, and arrived at the final shape.
The Final prototype form after Tanaka’s slimming down.
At the same time, engineers were modifying the existing 1.6-litre B6 engine from the higher performance version of the 323 into the B6-ZE, which revved higher (up to 7,200rrpm) thanks to a low-inertia flywheel, a stiffer crankshaft and wider overlap valve timing. Famously they even engineered the 5-speed gearbox to have a shorter and more precise throw (less than 45mm) which ended with a distinctive ‘clack’ courtesy of a metal end-stop, put there to emulate the feel of classic British sportscars. Ironically of course this was copying a piece of crude engineering the original 1950s UK engineers would probably have removed given the technology and budget Mazda had but their research had shown drivers loved the feeling of interaction it gave so it was faithfully copied. There is now a thriving trade in fitting various classic cars, including Elans and MGBs, with the reliable and now plentiful MX-5 5-speed gearbox…
This sectional view of the car’s layout clearly shows the engine is mounted almost entirely behind the front axle line for good handling and the fuel tank is buried in a much safer location than of old, ahead of the rear axle so it’s less likely to burst on rear impact.
The MX-5 went into production in the company’s Hiroshima plant and made its debut at the 1989 Chicago Auto Show, only 4 years after that original fibreglass prototype had been driven around Santa Barbara to gauge the public’s reaction. The finished car received an even more rapturous reception worldwide and has proven to be as reliable as it is attractive. During the launch, it was said to have been conceived and executed under a tightly focused design credo, Jinba Ittai (人馬一体), meaning “oneness of horse and rider”.
The launch at the 1989 Chicago Auto Show.
Despite Mazda’s concentration on the American market, the MX-5 was rolled out to world sales quite quickly and exceeded expectations in every market. It was a superbly executed product; attractive, fun to drive, good value and easy to use with a soft top that was more watertight and could be raised and lowered far more quickly than anything that came out of Abingdon in the 1970s.
Now in its fourth generation, the MX-5, ironically, looks likely to have a longer life on sale than the British Roadsters that inspired it, even though Mazda still refer to it as ‘their British sports car’.
Don’t forget, that we at Peter James know the Mazda MX-5 very well indeed. We have an insurance package specifically designed for Mazda MX-5 owners, tailored by our partners, the MX-5 Owners Club. So, give us a call and have your membership number at the ready!
Read our other blog on the MX-5 as a prototype here.
Or view the history of the MX-5 as a brief timeline here.
