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A New Legend: Early Development Of The Mazda Miata, Part I Of Iii In The "miata Trilogy"


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Orignally posted by "Duncan"

 

One tends to forget about a vehicle’s impact on the market when it’s been a sales success for over ten years. But then that’s the power of the Mazda MX-5 Miata, a design and concept that’s basically broken down all the barriers for compact sports cars worldwide. And it would be easy to think that something as simple and elemental as the MX-5 could be easily whipped together in just a few months, ready to be handed off to a waiting world. But it took quite a bit of time and planning before Mazda realized that what they were working on could be something really special.

 

The genesis of the Miata could be said to have begun nearly a decade before the car’s actual introduction with a visit to Hiroshima from American journalist Bob Hall in the spring of 1979. Hall had come to interview Mazda's managing director Kenichi Yamamoto about the company in general, as well as its future plans beyond the new RX-7. Yamamoto turned around the interview a little bit and inquired of Hall as to what kind of car he would like to see Mazda build. Hall, an enthusiastic sports car fan, went so far as to borrow a nearby blackboard and sketch out a rough rendering of a lightweight and low-cost roadster that could be built upon rear-drive 323 running gear.

 

Yamamoto didn’t show too much interest in the idea at first, considering that the company had just released the original RX-7 – which was still very much a low-cost, rear-drive sports car – at that time. And preliminary planning work was already progressing on the second-generation RX-7, not to mention other projects (like the important new front-drive 323 and 626 models). The company was growing every year and budgets were getting tighter, so it seemed that yet another sports car was out of the question. But then Yamamoto was asked by one of the company’s development testers if he wouldn’t mind driving a Triumph Spitfire they had just received. Curious, Yamamoto took up the offer and was impressed with the little Triumph’s sporting qualities. After that point, the possibilities for a lightweight sports car stayed with him.

 

I should speak briefly about the RX-7 here, as some may be asking why Mazda couldn’t just have stayed with one sports car. The company’s planners realized as early as the fall of 1980 that, given the ever-accelerating pace of vehicle development, the original RX-7 would only remain a viable vehicle through the early 1980s. Additionally, the RX-7’s triumphs in performance and styling made Mazda realize that they were quite capable of competing with the best cars in the world if they so chose. And it was decided by 1981 that the next RX-7 – coded P747 – would jump to the next echelon of performance to take on luminaries like the Porsche 911 and Nissan’s Fairlady Z (300ZX). Along with that would come a jump in technology and – perhaps most importantly to this story – price.

 

Flash forward to 1983, and another meeting between Mazda management and the motoring press. This time, the conference was strictly devoted to future plans for the next few years. Inevitably, the subject of sports cars came up, at which point someone asked about the apparent gap in price between the soon-to-come “upgraded” RX-7 and the previous model. It was an obvious problem, as not all of the current RX-7 owners could have been (or even should have been) expected to make the leap from a basic sports car up to its advanced successor. And while this loose planning session was underway, Mazda stylist Shunji Tanaka was in California, conducting a development drive in an early P747 prototype. Along with him for part of the trip was none other than Bob Hall, now working for the Mazda North America (MANA) product research and development team. As if by fate, Tanaka asked what car Hall might like to see Mazda build next – and Hall let loose with his old scheme for a low-cost, rear-drive sports car. Other executives caught wind of the American’s ideas later on, and were intrigued enough that the seed finally took hold.

 

The LWS (LightWeight Sports Car) movement gained a following this time around for two reasons. The first was the aforementioned gap in the line for a low-cost sports car under the RX-7; the second was a new emphasis within the company upon “outside-the-box” thinking. This last was spurred on by a new program begun in November of 1983 and called, curiously, “Offline Go Go”. The idea behind OGG was to keep designers and engineers fresh by encouraging them to break away from their usual conservative core projects (323, 626, 929, and B-series) and work on more exciting concepts of their own for a while. Some ideas to arise from this included a tiny “pocket” sports car, a modern off-road buggy and several studies on the traditional LWS ideal. Michinori Yamanouchi, leader of the OGG team, selected the LWS designs for further research. Though no one knew it at the time, great things would come from this humble beginning.

 

Yamanouchi appointed Masakatsu Kato as the director for project P729, and Kato requested theme sketches from both the Tokyo and MANA (California) studios to be presented in April of 1984. The Tokyo staff (under Yoichi Sato and Hideki Suzuki) chose to develop both a practical front-drive “FF” runabout and a more sporting mid-engine “MR” coupe, while the MANA team (led by former General Motors designers Tom Matano and Mark Jordan) stuck resolutely with a classic “FR” rear-drive roadster theme. Upon initial impressions of each studio’s work, it appeared that the Tokyo efforts clearly held the upper hand where raw styling was concerned. But there was still the matter of full-size clay models, which were due to be presented at the main Hiroshima studios in August of 1984. This time around, MANA’s clean Duo-101 design (markedly different in character from their Italian-inspired early drawings) was the hit of the show – though Tokyo’s mid-engine coupe was also an odds-on favorite.

 

Then the review process began. Although stunning to look at, the MR coupe was actually ruled out first. This outcome was based on an internal feasibility study from the Tokyo team (carried out by converting a 323 to the mid-engine layout) that proved such a design would be unduly noisy and rough riding unless the suspension was softened. And since no one wanted to compromise the sharp-handling layout, MR development was voluntarily ceased. This left the FF and FR proposals, both of which would be easy to engineer (based on either new or old 323 parts) and sufficiently comfortable for the majority of potential buyers. What sealed the deal for Mazda’s Hiroshima design board, however, was a video production created by the American design team extolling the virtues and mystique of the legendary rear-drive sports car layout – no doubt helped by the realization that the car’s primary market would definitely be the USA. In the end, the FR design won out and P729 would be a classic rear-drive roadster.

 

(As a side note, the FF coupe proposal did not expire but merely lay dormant for a little while. Updated with sleeker “organic” styling, a more practical four-seat hatchback body and the availability of Mazda’s unique 1.8-liter V6 engine, the MX-3 arrived for 1992 to high praise, being hailed in some circles as the true successor to Honda’s discontinued CRX.)

 

Rough engineering work on P729 began in September 1984, not long after the FR design had been selected. An independent British engineering company called IAD (International Automotive Design) was selected to build a running prototype of the American design, codenamed V705. After testing a wide variety of classic sports cars and noting their particular characteristics, IAD got to work on creating their own legend. In keeping with the original brief, off-the-shelf Mazda parts were used as much as possible – the 1.4-liter engine from a UK-market 323, front suspension from an RX-7 and rear suspension from the Japanese Luce (929) sedan. Hand-laid fiberglass panels were used to minimize IAD’s tooling costs, though Mazda engineers never seriously considered the material for mass production. It should be noted that IAD was selected for the prototype job mainly because Mazda wanted the car to have the feel of a classic British sports car, and apparently they succeeded when their creation was finally unveiled in August of 1985. On a trial test in California (pitted against an RX-7 and Yamamoto’s beloved Triumph Spitfire for general comparison), the public seemed to be immensely interested in the prospect of a new “old” sports car.

 

It was now October of 1985. With the design phase nearly complete (the American team had begun to make some last-minute refinements to its clay model) and the prototype’s engineering mostly sorted out, the LWS project was ready for final approval by the board of directors. But as always in a big company, there were more pressing issues to deal with and the idea went on hold for a while. The problems were, in fact, twofold.

 

The first issue was a conflict in available development resources between the proposed sports car and a more profitable Kei (light) car for the Japanese market, an area that Mazda had been basically absent from for some time. In short, the board believed that a new Kei car would be a sure-fire sales success, while a second sports car would only tie up a production line and produce minimal profit. Luckily, the company decided to partner up with Suzuki and let that company focus on Kei development, leaving Mazda free to tackle more impressive projects while borrowing Kei designs from Suzuki for sale as Mazda models. (This arrangement continues today.) The second issue, having very little to do with automobiles in a direct sense, dealt with the currency exchange rate between Japan and the United States – in effect, Japanese-built vehicles ended up being too expensive when their value in yen was converted to the weak dollar of the 1980s. Seeking a resolution, Mazda strengthened an already amicable relationship with Ford by splitting the costs of a new shared assembly plant in Michigan for production of the MX-6 and 626 lines (the company would also make extra profits from Ford’s purchase of Mazda components for the Probe coupe). This way, the money saved by using cheaper American labor would allow lower prices for all of Mazda’s offerings in the USA and free up more capital for further development on new vehicles.

 

Prospects for P729 were still shaky, but the LWS team felt strongly enough about the viability of both the car and the financial situation by December of 1985 to make a case for production to the Mazda board. And in January of 1986, the board – led by early proponent Kenichi Yamamoto – was finally swayed. The LWS project was set to go.

 

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Sources for this segment (gleaned from my local library):

 

Long, Brian. Mazda Miata: Renaissance Sportscar. 1998: Veloce, Dorchester, UK. (Now available in an American release from Motorbooks. Amazon.com's price is a reasonable $17.47.)

 

Yamaguchi, Jack and Thompson, Jonathan. Mazda MX-5 Miata. 1989: St. Martin's Press, New York. (Out of print, but supposedly available from Amazon.com for $22.00. And for a set of two beautiful hardcovers, that's not too bad.)

 

Yamaguchi, Jack. The New Mazda RX-7 and Mazda Rotary Engine Sports Cars. 1985: St. Martin's Press, New York. (I thought it was out of print, but it's apparently available from Amazon.com for the low, low price of just $65.50 either new or used. That may be worth it, though, because it does contain a great amount of extra history on Mazda's rotary development that I plan on sharing with you all later.)

 

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Once approval was attained for the basic P729 project, both the California team at MANA and the Japanese crew in Hiroshima – as well as the craftsmen at IAD in Worthing – were ready to get moving on the LWS design’s final form.

 

MANA began working on a definitive clay model during March of 1986, with lead designer Tom Matano looking to create a “Mazda face” – a unique, recognizable look that would identify the car as nothing else but a Mazda. But instead of going for a certain grille shape or front fascia style, Matano decided to craft an entire flowing, natural body language. (This was a concept repeated in multiple Mazda models over the next decade, the most notable being the third-generation RX-7 and the 1993 MX-6 coupe.) The final clay model, appearing very close in most details to what would eventually see the showrooms, was completed and sent to HQ at Hiroshima by July.

 

In the meantime, IAD had been working hard since May on both some rough engineering mules and a set of prototype steel body shells for evaluation. Some of these were even used to perform preliminary crash tests, proving (even at this still-early stage) that the car would be structurally sound. IAD staff then made a trip to Japan with their findings, in an effort to help Mazda’s engineers and planners make a quicker transition to production.

 

So it was that in July of 1986, the Mazda engineering and styling team in Hiroshima was presented with the task of finishing off P729. The styling department, led by Shunji Tanaka, began poring over the final MANA model. The first task was to remove what Tanaka saw as an extra “layer of skin,” making the car look a bit lighter on its feet. But then it seemed too long, so the Hiroshima took a step back and shortened the wheelbase – this after the MANA team had lengthened it for the benefit of easier engineering. One big problem caused by this shift turned out to be a good move after all – the battery, formerly located behind the seats, was moved to the trunk. Engineers grumbled, but the new placement actually improved the car’s already stellar weight distribution.

 

Oh, yes. Did I mention there was engineering work going on all this time?

 

The first technical task to come under consideration – the engine – was actually the easiest (by comparison) to complete. MANA’s original design had been crafted with existing componentry in mind, specifically the rear-drive parts from the old GLC. However, the engine tooling was by now outdated in terms of what people expected from modern cars, and the GLC (323 Familia) series had long ago shifted to front-wheel drive. So some conversion work was required.

 

In 1986, the hottest engine offered in the Familia line was the B6-DOHC, a twin-cam 1.6-liter unit used in the zippy Familia GT sedan. Since this was the most suitable powerplant available at Mazda (the 626 used a 2.0-liter four that was seen as too big), the B6 became the focus of chief powertrain engineer Kazuo Tominaga.

 

First task was to convert the engine to a longitudinal layout for the new rear-drive application. Then came the need to make the B6 rev higher, since the Familia GT had been tuned mainly for low-end torque. In the end, Tominaga and his crew were able to bump the redline up to 7200rpm – and most MX-5 drivers will tell you that’s where the 1.6-liter engine should stay most of the time.

 

Finally, there was a subtle concession to styling: oddly enough, the powertrain team felt that a car with such a classic layout deserved a classic look to its engine. Since they couldn’t use a set of twin carburetors thanks to modern emissions laws, they did the next best thing and shaped a beautiful new cam cover that evoked memories of Alfa and Lotus twin-cam motors. Even the oil pan was styled, with a set of cast-in cooling fins just like classic Italian race engines.

 

At the same time, a joint effort was occurring where the driveline was concerned. Originally, the plan had been to simply craft a basic sports suspension setup with independent double-wishbone front and rear layouts. This was done, and done very well, but another idea cropped up during development that would be a revolution for small sports cars. Noting that the inherently short drivetrain of a rear-drive roadster was generally prone to problems with axle windup and wheel hop on acceleration, engineers experimented with a way of stabilizing the whole assembly. On a hunch, one engineer built a simple frame out of aluminum plate and bolted it between the transmission up front and the axle at the rear. This worked very well in testing, providing a noticeable reduction in wheel movements under acceleration – along with the improved throttle response that comes naturally from a better grip on the road. With some refinements, the new idea became known as the Power Plant Frame (PPF) and was a major contributor to P729’s superb handling.

 

Other parts of the drivetrain were simpler to figure out. The standard five-speed manual transmission was borrowed from the RX-7, but engineers (among others within the company) agonized over how the shifter should feel. Eventually, they settled on the overall feel of a worn-in BMW gearbox, with just a touch of Ferrari’s characteristic “click” added for good measure. (Seriously, I’m not making this up.) In addition, the throws were shortened considerably – there’s just two inches of shifter travel between each gear.

 

Like the engine, brake and steering components were borrowed from the Familia line and suitably modified. Four-wheel discs were used, though rear drums had been briefly considered. And the manual steering rack gained a lighter ratio (power steering units would also be made available). Finally, stylist Tanaka crafted a beautiful eight-spoke alloy wheel design in the shape of the classic Minilite, but weight requirements imposed by the engineering staff meant that one spoke had to be knocked off – thus, the origin of the MX-5’s unique wheels.

 

Finally, with the major engineering work completed and Tanaka’s design finalized, the time had come to get the public’s opinion. Tanaka sent his clay model off to Pasadena, California in March of 1987 for a customer clinic. Of the 240 people polled, the majority liked the car’s look and basic concept. Mazda’s board was once again pleased, with the few remaining dissenters in the group agreeing that perhaps the frivolous little roadster project had some merit. Never mind the fact that the North American sales organization was practically salivating at the prospect of another great sports car to sell. With final approval in hand, final details had to be worked out.

 

Masakatsu Kato, the original planning director for the P729 project, had decided very early on that IAD’s prototypical fiberglass body and backbone chassis – effective as they were – would not be practical for mass production. So it had to be a conventional steel unibody, but numerous refinements and weight reduction measures were undertaken to bring the LWS down to the bare minimum. For instance, the hood was built from aluminum in order to lower the weight over the front end – likewise, the decklid was built of thin-gauge steel to achieve the same result in the back. The bumpers were also made out of lightweight materials, even going so far as to use polycarbonate mounting brackets rather than heavier aluminum or steel.

 

Also well underway was interior design, this being something of a secondary concern to the LWS team. That is maybe the biggest reason for the MX-5’s simplistic dashboard and seating layout. In concept, the look was supposed to represent the classic look of European sports cars past: a basic straight dash top, with cowled instruments for the driver and a central stack for ancillaries like the ventilation controls and audio equipment. The shifter, a tiny toggle wrapped in a blanket of leather, sits close at the driver’s hand.

 

The final issues, then, were resolved by September 1987. But there were a few extra matters left to settle before Mazda could begin the promotion machine.

 

First was suspension tuning. It was decided that the shocks would be optimized for best performance at 60mph, allowing the great majority of drivers around the world to get a good experience on a regular basis. Pre-production testing around the world bore out the wisdom of this decision. Other important considerations included the car’s exhaust note (with tests conducted among the Japanese public to determine the ideal sports car sound), interior comfort (deemed to be cozy but not too confining), and open-air feel (including measurement of the “hairstyle-retention rate” after high-speed runs). It was also decided that not only would the basic soft-top be a simple one-handed affair, but that a hardtop for all-weather use should also be made available as an option.

 

And that was it. By the spring of 1988, Mazda was prepared to reveal its well-hidden surprise to the world.

 

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Sources for this second segment are the same as for the previous post.

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Originally posted by "MazKid"

 

One thing I can add, the Miata concept model in '87-'88 used, get this, '87 626 GT wheels! My bro has some of the late '80s early '90s Mazda salesman training tapes and 2 other ones about Mazda designing and stuff, and on one they show a quick clip of the Miata with the 626 wheels, and it looked pretty odd...

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