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|Submitted by SuperUser on Friday, November 15, 2002 - 9:45am||
Today, Nov 15th, Mazda lifts the press embargo on publishing stories on the RX-8. Although a few places jumped the gun, we should see more and more stories on the RX-8.
These previews don't necessarily contain any new information to us, but they do give us a good idea of what to expect once the RX-8 hits the streets mid-next year.
Archive of Article Text!
There are more than a few automobiles that have, over the years, become interchangeable, even synonymous with a particular automaker. Porsche’s 911 is only the first of several to come to mind. But it’s rare when a marque becomes linked more to an engine than an automobile.
It’s been more than seven years since Mazda pulled its RX-7 off the American market (though it has remained a low-volume fixture in Japan). Sure, there’s the Miata, but since the demise of the bigger, faster and more iconic RX-7, Mazda has clearly lost much of its identity. Yet one could make a good argument that it wasn’t the RX-7 that so symbolized the Japanese automaker, as the engine its hood.
There was a time, 30 years back, when the Wankel rotary was being hailed as a revolution in the making. Incredibly small and bafflingly simple, it was also surprisingly powerful. No wonder automakers as diverse as General Motors and Germany’s old NSU began laying plans to make the rotary engine a centerpiece of their powertrain operations.
But like so many other over-hyped alternatives to the piston engine, the Wankel couldn’t live up to initial expectations. It proved low on mileage, high on emissions and, as Mazda catastrophically discovered with early rotary-powered cars like the RX-2 sedan, the engine was prone to early, catastrophic failures. It nearly drove the automaker into bankruptcy—one of the reasons why Ford Motor Co. now owns a controlling stake in Mazda.
Japanese engineers eventually resolved the problem, and though the rotary would never again vie for mass market status, it made a phoenix-like comeback, the primary reason why the original RX-7 developed a cult-like following. Spinning at speeds that would strain a Formula One engine, the Wankel turned out gobs of power that street racers craved, and proved its mettle on the professional circuit by capturing the checkered flag at Le Mans in 1991.
Unfortunately, Mazda again made some fundamental mistakes, including the belief that the RX-7 could steadily move up-market. There’s no question the last-generation RX-7 was a fine piece of engineering--fast, stylish and sophisticated. But it was just too expensive and complex, and fell flat on its face, forcing Mazda to pull it from the market in 1995.
Cult of speed
All this as a long prelude to the centerpiece of this story: the return of the rotary, and the RX sports car. An all-new version of the engine, dubbed “Renesis,” provides the heart and soul of the new RX-8. A modest though justifiable change in nomenclature hints at some significant differences in the sport car’s fundamental design. And if Mazda planners are right, these changes may generate significantly higher demand, especially from diehard fans who otherwise could not justify the functional compromises of a 2-seater or 2+2.
Prototypes of the RX-8 have been making the rounds of the global auto show circuit for several years now, so the basic shape is going to come as no surprise. It’s actually a good bit more refined than the early show cars, a sleek reinterpretation of the classic RX theme.
Though it weighs in at around 2900 pounds—a bit less than the last-generation RX-7, the new car is slightly taller and wider, its wheelbase stretched 275 millimeters, to 2700 mm. The wheels are also pushed much further out towards the corners, while the powertrain has been moved 140 mm rearward, and lowered 40 mm. That only gives the new RX-8 a 50/50 weight balance, but a much lower center of gravity, despite the added headroom.
The added dimensions serve a precise purpose, turning the car into a functional four-seater. But that wasn’t enough for Mazda designers. They wanted this car to function more like a sedan than coupe. Leaving aside the Renesis rotary for the moment, the centerpiece of the car’s design is what Mazda has dubbed the “Freestyle Door System.”
That’s certainly more appealing a term than “suicide doors,” especially with Mazda promoting the idea of finally being able to provide the usable space of a family sedan without sacrificing the performance of a sports car. Designed to operate only after the front doors are opened, these slightly downsized access hatches are an integral part of the overall body structure. That’s critical because there are no center, or “B,” pillars in the RX-8, which would normally help to absorb and distribute the forces from a side impact.
Mazda compensates by creating a “virtual pillar in the rear door,” explains safety engineer Hikoaki Takeshita. Each door has side impact beams that effectively latch onto this virtual pillar when the vehicle is closed up. A reinforcing steel pipe connects to the body through strengthened door latches, and catcher pins at the bottom of the door maintain structural integrity and positioning. Mazda officials insist the design is so effective, it doubles the rigidity of the RX-7. The automaker expects the RX-8 to achieve top government crash ratings in Europe, Japan and the U.S.
The RX-8 has significantly more rear seat and leg room than a traditional 2+2. That’s critical, according to Product Development Director Joseph Bakaj, for the new Mazda aims to attract the type of buyers who’d love to own a sports car but until now couldn’t, perhaps because they had a family and needed more usable space.
The recently-introduced Mazda6 has been generating quite a buzz, particularly for the refined quality of its interior. The RX-8 takes that several steps beyond. The exterior theme reaches into the passenger compartment, starting with a center “power bulge” that sweeps through the cabin in the form of a functional center console that extends into the back seat. It features several useful storage compartments, as well as cupholders. Indeed, Mazda put a premium on functionality. There’s a spot for a tissue box, another for your sunglasses. And the center of the rear seat provides a trunk pass-through.
And that trunk, by the way, is big enough for two golf bags. But at least in the Japanese version, there’ll be no standard spare tire. At the moment, Mazda is debating whether one will be provided in the U.S.
There’s enough room for a six-footer, though it would prove a bit cramped for a long journey, especially with the undersized back windows—which do not roll down. We’d also like to see Mazda make the front seats slide forward, as they do in most coupes, for even easier access to the rear.
The RX-8 we spent most of our time with at the Mazda test track outside Hiroshima was painted an appropriate “Velocity Red” mica. The interior featured what might be called a saddle shoe mix of black and burgundy, a handsome and elegant blend.
While automakers, in general, have been getting better at coloring and graining plastics, Mazda goes one better with the tasteful use of lacquered, or piano black, accents. The most obvious touch is the audio system, designed in the shape of a CD. It sounds good, and it looks as nice as anything from Bang & Olufson.
The gauges are large and easy to read, though some might take fault with the decision to go with a digital speedometer display. Everything else is analog.
But let’s face it, the RX-8 is all about rotary power. And the Renesis is an intriguing update of the Wankel design.
Early problems with the rotary seals have been resolved. But in developing the RX-8, Mazda faced a number of other challenges. For one thing, it had to drive down cost, one of the reasons it chose not to turbocharge the new engine.
Emissions and fuel economy were even more challenging. A major issue was the fundamental design of the valveless rotary, since for a brief interval, the rotor would leave open both the intake and exhaust ports. With the new, 2-rotor Renesis, the three exhaust ports have been moved to the side rotor housings, so they can be completely closed when the intake port is opened. That eliminates unintentional exhausting of unburnt hydrocarbons.
And earlier rotary designs tended to produce inefficient burns because they operated at lower temperatures. The Renesis has been designed to capture unburnt hydrocarbons and carry them over to the next cycle. The carmaker claims the new engine will be able to meet both the tough new Euro-4 and U.S. LEV-II emissions standards.
Mileage, meanwhile, is expected to come in at 18-19 mpg in the U.S. city cycle, and 23 to 24 mpg on the highway.
For potential customers, what is likely to matter most is performance, and the top-line version of the normally-aspirated Renesis (the only version coming to the U.S.) produces 250 horsepower, the same as the turbocharged rotary in the last RX-7. On paper, that isn’t all that much these days, not when you consider Honda is pumping 240 hp out of the new Accord V-6. But the lighter engine, mated to a short-throw six-speed manual, gets the car going in a hurry. The one drawback is that power tends to come on at fairly high rpm, so drivers will want to keep the engine revving above 4000 rpm if they want maximum performance. Renesis’s redline is a full 10,000 rpm, so the car flies when it gets going, but it’s no rocket off the line.
Our long trip to Japan brought all too brief a run behind the wheel. We’ll have to wait until early next year to put the RX-8 through a more thorough road test. But the Mazda test track did offer a variety of surfaces, plenty of turns and some reasonable elevation changes, enough to get a feel for both engine, body and suspension.
The virtual B-pillar design clearly works. This car shows absolutely no body flex. The suspension keeps body roll to an absolute minimum, yet it is reasonably good at filtering out road harshness. The steering literally snaps the car through tight turns.
The new RX-8 will hit the streets in Japan before year’s end, but won’t make export markets until sometime in early 2003 as a 2004 model. By then there could be a few more changes, but the car we experienced doesn’t need much work. We’d like to see a little more low-end torque—which Mazda officials admit they’re also studying ways to deliver. But the new RX-8 has succeeded admirably in its mandate of blending both sports car performance with the functionality of a sedan. It’s a sleek and sexy package with a unique powertrain that’s going to continue to appeal to a rotary cult. We expect the RX-8 to be welcomed heartily when it finally hits the streets.
2004 Mazda RX-8
Base price: $25,000 (est.)
Engine: RENESIS 1.3-liter rotary, 250 hp/159 lb-ft
Drivetrain: Six-speed manual transmission, rear-wheel drive
Length x width x height (mm): 4435 x 1770 x 1340
Wheelbase: 2700 mm
Curb weight: 2900 lb (est.)
EPA City/Hwy: 18/23 mpg (est.)
Safety equipment: Four-wheel anti-lock brake system, Electronic Brake Force Distribution, Dynamic Stability Control. Dual-stage deployment SRS airbag on the driver's side and standard SRS airbag system on the passenger's side, intrusion-minimizing brake pedal, tire pressure monitor
Major standard equipment: AM/FM/CD/cassette, power windows/doors locks, tilt/telescopic steering wheel, 18-inch aluminum alloy wheels
Warranty: Four years/50,000 miles
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