While Pan Speed was looking to squeeze as much performance out of the Renesis engine as possible, Revolution has taken a completely different approach and created a custom, peripheral-ported 20B for this application. The car has so far only done one shakedown test and this is the first time it’s been shot by a magazine. Suck on that, Option! The idea behind the project was to get people more interested in the RX-8, a car that since it’s introduction back in 2003 hasn’t done much to get die-hard rotary heads away from their turbocharged vehicles. The highly strung and carefully engineered Renesis was developed to meet ever-stringent emissions regulations (and ever-tightening budgets) and thus just hasn’t responded well to aftermarket tuning. Forced induction has on average resulted in moderate power gains, and trying to extract more power from just intake and exhaust upgrades has at times achieved just the opposite.
Revolution’s Aoki-san knew there was only one way to get the required power levels he was shooting for without resorting to forced induction, and that was to get rid of the Renesis altogether and go for a naturally aspirated three-rotor 20B instead. In typical Revolution fashion, the build began much as a race team would approach the construction of a dedicated race car: with a full strip-down of the car to the bare chassis. At this point a custom rollcage was fabricated and welded in place, helping to boost rigidity particularly in the center of the car where—due to the ingenious way the rear doors open—there are no B-pillars. Hydraulic jacks were also welded in place, items that further exemplify just how serious Revolution is with these kinds of projects. The use of the slightly longer and heavier 20B required additional bracing in the engine bay, as well as custom mounting points that would move the engine as far back as possible for optimal weight distribution. A custom transmission tunnel was cut and finished off in dry carbon, ready to accept a Hewland six-speed sequential transmission. Custom Revolution adjustable dampers were then fitted and mated to stiff Swift springs, making the most of the neutral handling characteristics of the RX-8. AP Racing calipers all round take care of the braking, biting down on Project Mu slotted discs with matching pads.
Aoki-san wanted to keep the looks of the car relatively simple, and proceeded to change only what was going to have a direct benefit on performance. The front bumper remains but is joined by a very sturdy carbon-honeycomb composite under-panel, attached directly onto the chassis. You can put all your weight on the protruding front lip splitter without any problems, indicating the amount of aerodynamic downforce it could potentially generate. A vented carbon-fiber hood helps extract hot air from the engine bay and shed some weight from the front of the car. However, front and rear carbon doors provide the biggest weight reduction, the rears even doing away with the windows. More carbon can be found in the rear windshield, which replaces the standard glass window just like on Super GT cars. Rear downforce is generated via a high-mounted carbon spoiler, helping keep the rear of the car planted at higher speeds. Rays Engineering came into the project by supplying a lightweight set of Volk Racing RE30s, sporting a new type of finish called Hyper Bronze Premium. The 18x9.5-inch rims are shod with sticky Hankook Ventus Z221 tires—the same tires used on their FD3S time-attack car.
The donor 20B was taken apart and rebuilt using 13B housings and was peripheral ported to guarantee the highest performance from the setup. Special Revolution rotors were used to achieve a 9.7:1 compression ratio, and a complex exhaust manifold was created to help keep just the right amount of backpressure throughout the rpm range. Aoki-san chose to deliver oil via a dry sump for two reasons, the first being that it could be mounted low to keep a low center of gravity, therefore benefitting handling, and secondly, to make sure optimal oil circulation and pressure is maintained even through the most grueling conditions. The engine breathes via a custom triple-throttle setup, mounted inside a specially built airbox that’s fed by large tubing directly from the ram-air scoop at the front of the engine bay. Air is throttled through 50mm throttle ports and mixed with fuel supplied by 1,000cc/min injectors, ignited by six NGK spark plugs. Revolution had ARC create a custom radiator setup with extra-long aluminum piping as well as twin oil coolers to keep the high-revving engine cool. Engine management is taken care of by the Motec M4, which is joined by race-spec wiring and connectors. To mate the engine to the Hewland sequential, a custom adapter plate had to be made, along with a custom linkage for the shifter in the cabin. The driveline upgrades are completed with an ATS carbon LSD to handle all 414 hp the engine has to offer. Yes, again, that’s naturally aspirated.
Gently open the featherweight driver’s door and you’ll see that Revolution sourced a left-hand-drive car for better weight distribution. The race car attention to detail continues: The carbon dashboard retains only a skeletal shape of the standard item, with all switches and instruments completely eliminated. Due to the rearward-shifted driving position, the steering column has been extended and an adjustable pedal box allows the driver to set up the controls as he pleases. Even the pedals are made of carbon fiber. All switchgear has been positioned on the carbon transmission tunnel, around the tilted gear selector. The only instrumentation is the Motec LCD display, encased in a carbon-fiber box at the center of the steering wheel. With no view out of the back due to the carbon rear windshield, a small LCD screen replaces the rearview mirror, displaying the view from the rear back-up camera.
With its buzzing 414 hp and 2,500-pound curb weight, the Revolution RX-8 has the potential to record some stunning track times. The car has however been put on the back burner for a few months so that the Revolution team can prepare for another season of time-attack, where they will be trying to extract an even faster Tsukuba lap out of the RX-7, before (we suspect) carting it off to Australia once again for the World Time Attack Challenge. Maybe we’ll see a dual performance?
Behind The Build
Legit, in dog years
Greater Tokyo, Japan
Baywatch, Knight Rider
We aim be like Mitch Buchannon!
Mazda SE3P RX-8
414 hp / 289 lb-ft of torque
Engine 20B engine, 13B housings, 643cc 9.7:1-compression rotors, peripheral ported; Revolution custom dry-sump system, exhaust manifold, titanium exhaust system, carbon airbox, carbon ram-air scoop, 50mm individual throttles, high-pressure fuel pump, 1,000cc/min injectors; NGK Racing R6725 #11 plugs; ARC custom radiator with air-separator system, aluminum radiator piping, custom twin oil coolers; Motec M4 ECU
Drivetrain Hewland six-speed IGT-A sequential transmission; custom bellhousing adapter; ORC triple-plate Super GT clutch, 303 lightweight flywheel; ATS carbon LSD, 3.909:1 final-drive ratio
Suspension Garage Revolution racing dampers; Swift 18kg/mm front springs; 10kg/mm rear springs
Wheels/Tires Rays Engineering Volk Racing RE30 wheels (18x9.5-inch +40mm offset front and rear); Hankook Ventus Z221 265/35-18 tires
Brakes AP Racing six-piston front calipers, four-piston rear calipers; Project Mu 355mm two-piece slotted front rotors, 328mm two-piece slotted rear rotors, 999 brake pads
Exterior Garage Revolution carbon-fiber front under-panel, GT cooling hood, GT high-mount wing, front and rear doors, rear windscreen; Craft Square carbon-fiber mirrors
Interior Garage Revolution race-spec chromoly rollcage, bucket seats, steering wheel, custom reinforcement to front & rear, chassis spot welding, hydraulic jacks; Extended steering column with tilt-up Super GT style boss, adjustable pedal box with dry carbon pedals, dry carbon dashboard, transmission tunnel, selector console and switchgear, custom gear selector and linkage; Takata Racing harnesses
Electronics LCD screen for rear camera; Motec wheel-mounted data logger/display