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RX-8: 2004 to Present

The 2004 RX-8 is both a return to the RX-7's roots and a completely different sort of sports car. "It would be easy to simply think of the RX-8 as the latest version of Mazda's halo car — an heir to the sports car throne left vacant since the last U.S.-spec RX-7 was sold here almost a decade ago," Karl Brauer wrote after's first encounter with the new RX-8. "While the RX-8 will be all of those things, its redesigned rotary engine, reverse-opening rear doors and room for four adults make it far more."

A key element in the RX-8's mix is the newly designed, naturally aspirated "Renesis" version of the good, old 13B rotary. "The most important Renesis change relates to the location of the intake and exhaust ports," Brauer reported. "Because a rotary engine has no valvetrain, the location of these ports is crucial to the engine's performance. In the previous engine, these ports were located on the outer edge of the rotary housing, but in Renesis they are on the side of the rotary chamber. Unlike the previous design, this location allows engineers to completely close the exhaust port before the intake port opens, and vice versa. It also allows them to use 30-percent larger intake ports than before, along with a variable intake system that optimizes air flow." What that all means is that, even without a turbo or any other forced induction scheme, the Renesis 13B in the RX-8 makes a stellar 238 hp at 8,500 rpm when mated to a six-speed manual gearbox and 197 hp at 7,200 rpm when ahead of a four-speed automatic transmission. The redline was now up at a stratospheric 9,000 rpm.

But just as important as the newly optimized engine, the RX-8 is a true four-seater with access to the rearward accommodations through a set of rear-hinged doors. And it's a four-seater that still has a sports car's balance thanks to 50/50 weight distribution (the Renesis engine sits back in its chassis just like the 12A did in the first RX-7) and a supple chassis with double-wishbones up front and a multilink independent system in the rear. It feels, in many ways, like a civilized and livable version of the chassis in the last RX-7. Naturally, four-wheel disc brakes with ABS and rack and pinion steering are also part of the package. And beyond all that, the RX-8 weighs in at just 3,029 pounds in manual transmission form.

"There is nothing like the RX-8 currently available," Brauer concluded on its introduction, "so when they say competitive we aren't sure where to look (which, going back to the idea of creating a unique and compelling vehicle, is great for Mazda). We'll assume that the new Nissan 350Z is among the car's potential competitors simply because Mazda's own people were quoting curb weight comparisons."

Naturally, at the first opportunity we pitted the RX-8 against the new 350Z in a comparison test late in 2003. "Whether our conclusion meshes with your idea of the perfect sports car depends on what you're looking for," wrote Ed Hellwig in that test, "but rest assured that either car delivers outstanding performance, eye-catching looks and enough features to keep you comfortable. We may have picked a winner, but when you have a choice of two sports cars this good at these prices, nobody loses."

That "nobody loses" may be true, but picked the RX-8 as the winner. "Generating 238 horsepower from a measly 1.3 liters, the RX-8's rotary engine is a marvel of efficiency and smoothness," Hellwig reported. "Its small size and minimal weight allow a more advantageous placement within the car, giving it an almost midengined feel. Its power peaks at a lofty 8,500 rpm (redline is 9,000), but the real surge begins around 5 grand so you're not completely left out in the cold at midrange speeds. As you might expect, low-end power is notably absent, a trait that's magnified after a drive in the torque-rich 350Z that never exhibits a weak spot.

"Track testing yielded a best 0-to-60-mph time of 6.6 seconds and a quarter-mile run of 15.1 seconds. Without much off-the-line torque, the RX isn't much of a stoplight king, but once underway it makes up ground quickly. Its quarter-mile speed of just over 92 mph puts the Mazda about 5 miles per hour behind the Nissan. The numbers don't lie, if you're looking to dust off local high schoolers, the RX-8 isn't the car to do it with."

But the car's compensating virtues were manifest. "Unlike the Z that hammers its way through bends," we said then, "the RX-8 glides through them in a manner that's far less intimidating. Its moderate body roll gives you a better sense of how hard the car is working compared to the ultrastiff 350Z, and when the grip does finally run out, it does so in a more progressive and controllable fashion. Midcorner bumps are soaked up without a hitch, and even the stability control system stays out of the way until absolutely necessary. And all this despite the fact that it has none of the teeth-rattling tendencies of the Nissan."

Despite being separated by a full quarter century, what we wrote about the RX-8 isn't that much different than what Car and Driver concluded about the first RX-7. That old RX-7 and the new RX-8 may be different in every detail, but they're really just two expressions of one idea. And it's still a very good idea.


Mazda unveiled the RX-8 at the 2001 Tokyo Motor Show.

Mazda exhibited the RX-EVOLV at 1999 Tokyo Motor Show, as a proposal for a new sports car with an innovative packaging concept based on the next-generation rotary engine. Mazda received a favorable response for the concept car from customers all over the world. At the 2001 North American International Auto Show, Mazda also exhibited a design and engineering model of the RX-8, which was a result of our corporate desire to realize the potential that the RX-EVOLV showed.

In developing the RX-8, Mazda strove to realize conflicting goals: delivering a vehicle with striking, sporty styling with a superior blend of handling and performance, while providing ride comfort and the functionality for four adults. A key factor in achieving these goals is the RENESIS engine, the next-generation rotary powerplant, which is more compact and higher-powered than previous rotary engines, featuring a water cooled, two-rotor configuration. This delivers a maximum output of 184kW/8500rpm and 216Nm of torque at 7500rpm, while achieving improved fuel efficiency and cleaner emissions. The RX-8 incorporates both genuine sports car styling and an interior package spacious enough for four adults. It also includes a further refined front-midship layout as well as a freestyle, four-door configuration without a center pillar. Exceptional driving performance comes through 50:50 front/rear weight distribution and small yaw-inertia moment. With superior practicality, the RX-8 will meet the expectations of a wider range of customers, not only sports car fans.

The RX-8 is an entirely new sports car embodying Mazda's "Zoom-Zoom" brand message to the maximum, by pursuing "Distinctive design," "Exceptional functionality," and "Responsive handling and performance."

DISTINCTIVE DESIGN Unprecedented Sports Car Styling Encapsulating Space for Four Adults The form of a genuine sports classic Mazda has produced many sports cars with exciting styling that stand the test of time, such as the first-generation Cosmo Sport, the RX-7 and the MX-5/Miata/Roadster. Following this tradition, Mazda designers were determined to give the four-door, four-seater RX-8 unprecedented styling. They began by sculpting a body with a dynamic feeling of motion. Exciting surfaces run from the aggressive front air intake along the body to the trunk lid. The classic rear-wheel drive sports layout places visual emphasis on the rear tires. Short front and rear overhangs, and characteristic overfenders, underline the vehicle's look of stability. The styling is a classic statement of beauty in motion, reminiscent of a top athlete.

This is the perfect embodiment of Mazda's new design philosophy of "Emotion in Motion." The adoption of the freestyle door system, for four doors without center pillar, means the RX-8 is an unprecedented combination - the look and feel of a genuine sports car in a four-door vehicle. The shape of the rear pillars and rear window pay homage to the first-generation Cosmo Sport and RX-7, yet its innovative package provides enough space for four adults.

Low, dynamic front end Aggressive lines extending from the air intake along the low hood that only a rotary engine with its compact design can make possible; a power bulge in the center of the hood with a rotor as the motif; a bumper fascia emphasizing the "cubic" effect; and short front overhang all combine to create a dynamic sports car image and emotional atmosphere, enhancing the car's Zoom-Zoom spirit. In addition, the front fender wheel arches stand high and clear of the low hood to visually manifest the RX-8's power and provide the driver a clear view of the front corners of the vehicle.

Rear view with emotional and cool styling cues The rear view is designed to create a vivid impression as the car drives away - an important consideration for a sports car. This is partly achieved by the RX-8's short rear overhang. Rear combination lamps receive a mechanical touch through the addition of chrome accents, a rotor-shaped rear fog lamp is located low in the center of the bumper, and the dual exhaust pipes are placed to the left and right. Taken together, these elements create an impression that is simultaneously emotional and contemporary.

RESPONSIVE HANDLING AND PERFORMANCE High-mount backbone frame To give the RX-8 the rigidity a genuine sports car demands, a strong, high-mount backbone is located in the upper part of the transmission tunnel. This backbone runs from the front bulkhead through the cabin to the rear bulkhead and functions as the main frame of the chassis, enhancing rigidity and allowing reduction of body-panel thickness and weight. It also contributes to safety in the event of a collision.

Closed-section power plant frame (PPF) The lightweight closed-section PPF locks the entire powertrain - including the differential gear - into a single rigid unit. This mechanism enhances direct and linear acceleration feel and crisp shift operation with plenty of sports car driving pleasure.

One-piece, carbon-fiber propeller shaft Even with a 2,700mm wheelbase, the RX-8's front-midship layout drastically shortens the distance from the gearbox to the differential. This allowed engineers to install a one-piece propeller shaft made of carbon fiber, which further reduced weight.

Double-wishbone suspension at front and multi-link beam suspension at rear Long-arm double-wishbone suspension at the front and multi-link beam suspension at the rear provide ideal suspension geometry. Long arms and links achieve suspension linearity and roll control, while optimum roll-center height maximizes suspension stroke. Tires remain perpendicular to the road throughout the length of suspension travel for superior grip, even under the hardest cornering. The result is superb roadholding with no sacrifice in ride comfort. Thanks to the greatly reduced yaw-inertia moment (a result of the front-midship layout), optimum roll-center height and tire camber control, the RX-8 delivers a sharp response to steering inputs and enhanced controllability. This chassis and suspension design also allowed the adoption of large-diameter 18-inch aluminum wheels with high-grip 225/45ZR18 tires. Rack-and-pinion power steering gives accurate feedback on road conditions, while an electric power-steering pump delivers precisely the right amount of assist to match driving conditions. One further benefit of an electric power-steering pump is improved fuel economy, as electrically driven steering, as opposed to the typical belt-driven system, does not drain power from the engine. Large, 17-inch ventilated discs on all wheels give sure, positive braking in support of safe, sporty driving. Six-point rubber mounts on the rear subframe improve both driving stability and road noise.

GREATER SAFETY AND CONSIDERATION FOR THE ENVIRONMENT Improved performance to side-collisions Placing the RENESIS engine front midship realized a sufficiently large crushable zone between the engine and front bumper. This ensures improved impact absorption in head-on and offset frontal collisions. At the same time, the RX-8 also provides superior performance in side-impacts. It has a highly rigid body structure for a sports car, in spite of the pillar-less, wide-opening design. To achieve this, a large number of measures were adopted including a rigid underbody frame, the high-mount backbone running through the cabin, and carefully planned chassis reinforcements. A reinforcement structure forms a virtual center pillar built into the door frames, while top and bottom latches lock the rear door to the body. In addition, a safety lock mechanism allows the rear doors to open only if the front doors are open, too. Active-safety measures include large-diameter 17-inch ventilated disc brakes on each wheel, a 4W-ABS (four-wheel anti-lock braking system), and newly adopted DSC (dynamic stability control) that senses when the vehicle begins to skid or spin, and counters it by controlling engine torque and applying the brakes as needed.

Tackling environment problems Zero overlap between the intake and exhaust ports results in enhanced thermal efficiency for the RENESIS engine, allowing a much leaner air/fuel mixture for fuel efficiency when idling compared to the 13B-REW rotary engine in the RX-7. In addition, thanks to the efficiency inherent in the rotary engine, the RX-8 operates with a lean mixture even during high-speed high-load operation. A high compression ratio and newly developed ultra-fine fuel injectors make virtually perfect combustion possible across the engine's entire speed range. Rotary engines also have structural qualities that cause them to generate less NOx (nitrogen oxide) than conventional engines. RENESIS' side-exhaust layout retains unburned HC (hydrocarbons) for the next combustion cycle, further lowering emissions. In addition, a newly developed catalytic converter for the rotary engine is teamed with a double-skin exhaust manifold that maintains a high exhaust-gas temperature to improve catalyst activation on engine start, even in cold conditions.

Years Available: 2003-onwards Engine: 'RENESIS' 13B (1308cc) twin rotor (2 x 654cc) EFI Transmission: 6 Speed Clutchless Auto with paddles behind steering wheel Power (Approx.): 246 hp (184kw) @ 8500rpm Torque (Approx.): 159 Lb/Ft (216Nm) @ 7500rpm Weight (Approx.): N/A Chassis Prefix: N/A

Specification: N/A

Original Cost: Approx. $60000 AUD

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