Mazda RX-8 on display at the 2006 Washington Auto Show.
The RX-8 was designed as a front mid-mounted, rear-wheel drive 2+2 coupe. The car has a near 50/50 weight distribution, achieved by mounting the engine behind the front axle and the gas tank ahead of the rear axle. Weight is trimmed through the use of materials such as aluminum (hood, trunk, roof, and rear doors), fiberglass for the body panels and a carbon fiber composite drive shaft.
The car features a pair of rear-hinged “freestyle” doors (similar to suicide doors) in order to provide easier access to the rear seats. The RX-8 has no B-pillar between the front and rear doors, with the leading edge of the rear door acting as a ‘virtual pillar’ to maintain structural rigidity. Because of the overlapping design, the rear doors can only be opened when the front doors are open.
The RX-8 is powered by a 1.3 L (1,308 cc) naturally-aspirated RENESIS 13B Wankel-type rotary engine, which features newly designed side intake and exhaust ports. The engine is smaller and lighter than previous rotaries, primarily due to the lack of a turbocharger and associated parts. Though the engine is only 1.3 L, it is rated to get 18 mpg in the city.
The engine is designed in various configurations for different models, but in its most powerful setup develops 250 PS (247 hp, 184 kW) at 8500 rpm with a sustained red line at 8500 rpm, peak red line of 9000 rpm and fuel rev limit/cut-off at 9500 rpm. It won the International Engine of the Year and Best New Engine awards in 2003 and holds the “2.5 to 3 liter” size award for 2003 and 2004.
The power is delivered to the rear wheels via a five- or six-speed manual gearbox or a four-speed automatic through a torque sensitive limited slip differential which is standard with manual shift transmission & optional for the automatic models. With model year 2006, a 6-speed automatic transmission was introduced to replace the 4-speed automatic.
In late 2003 Mazda issued a press release stating that the actual horsepower of the RX-8 could be up to 5% less than previously advertised. Mazda offered to buy back any of the affected vehicles sold in the United States. Those who chose to keep the cars were given other incentives such as free maintenance, parts, and accessories.
In August 2006, Mazda announced that a miscalculation with oil metering had led to the engines in a few RX-8s to experience problems with severe power loss and rough idle. Mazda voluntarily recalled all 2004 and 2005 and some 2006 models to test for this problem, and all engines that failed a vacuum test were replaced at no charge, even if the car was out of warranty. The catalytic converter and leading spark plugs were also checked and replaced as needed. Mazda extended all recalled vehicles’ drivetrain warranty to 5 years/60,000 miles. Most affected vehicles were in hotter climates, and were exposed to high traffic, low rpm driving and long idle periods. Mazda estimated that less than 1% of engines needed to be replaced. For vehicles that did not require an engine replacement, Mazda updated the PCM to provide more oil injection at idle and under low rpm driving.
The RX-8 is available in various models in different markets around the world. Standard models include:
* 6-speed manual “High Power” with an output of between 170 kW (228 hp) and 177 kW (237 hp) and a 9000 rpm redline (Japanese models produce 184 kW (255 hp) due to the availability of higher octane fuel)
* 5-speed manual “Standard Power” tuned to 141 kW (189 hp) with the redline reduced to 7500 rpm. The 2006 models have been beefed up with close to 200bhp (The exact power needs to be clarified).
* 4-speed automatic tuned to 141 kW (189 hp) in some markets, while the U.S. automatic is claimed at 197 SAE net hp (158 kW)
* 6-speed automatic (available in the U.S. market as of 2006) developing 212 hp (170 kW) with a redline at 7500 rpm.
Shinka/Evolve/Sports Prestige Limited
Mazda introduced a special Shinka edition to the U.S. market in 2005, and to the UK market in 2006 where it was branded as the Evolve. New features included Shinka badges on the B-pillar, new paint colors (Black Cherry Mica, Copper Red and Phantom Blue), re-styled mirrors, alcantara-trimmed leather seats, updated component materials, and enhanced chassis and suspension tuning. Power output remained unchanged from the standard models. This model was also offered in Japan as the Sports Prestige Limited RX-8.
In May 2006, for the UK market, Mazda released the RX-8 PZ, a version developed jointly with the famous motorsports company Prodrive. Only available in six-speed manual, it features custom wheels, mirrors, and spoiler, with significant revisions to the suspension which improve the handling. Only 800 were made at an MSRP of £25,995 including 17.5% VAT. It is available in two colours, Galaxy Grey and Brilliant Black.
At the 2004 North American International Auto Show, Mazda unveiled the RX-8 Hydrogen RE concept car, designed to run on either hydrogen or gasoline. In February 2006, Mazda revealed that it would start leasing a dual-fuel RX-8 to commercial customers in Japan, and in March 2006 announced its first two customers, claiming the first fleet deliveries of a dual hydrogen/gasoline production car.
Mazda had initially planned to release a two-seat coupe version of the RX-8, but the development costs were deemed too expensive and the model was canceled. The standard RX-8 is due for a redesign in 2009, and will be launched as a 2010 model.
As of October 2006 the RX-8 has won at least 37 international motoring awards including the 2003 Japanese Car of the Year, Australia’s Wheels magazine’s Car of the Year for 2003, the 2004 Singapore Car of the Year, the 2004 US Best Sports Car, and several UK Best Car Awards. It was also named on Car and Driver magazine’s Ten Best list for 2004, 2005, and 2006.
The car is used in the Formula Woman racing series in the United Kingdom which started in 2004, Mazda uses one of its car to compete in the Britcar championship. Drag racer Abel Ibarra uses a 4-rotor powered spaceframe version of the RX-8 to compete in the NHRA Sports Compact series and is used in drifting events by Kouichi Yamashita and Rod Millen for the D1 Grand Prix and Formula D series.