Make no mistake about it--what you see here is not a street car. Sure, it is one of 68,589 FD3Ss that rolled off Mazda production lines for a decade beginning in 1992, and yes, it still retains its factory unibody core, five-lug hubs and DOT tires. But that's where the similarities between it and any other road-going RX-7 end. This car was re-born for one purpose only: to give Aoki-san of Garage Revolution recognition as the world's best rotary tuner.
Enter the world of Japanese time attack racing and its ground zero: Tsukuba Circuit. Priority number one for any rising JDM tuning shop is to prove they can hang with the best, and the most direct way to do that is by building a winning car for the track's annual Super Battle event. Placing at the top is such a prestige that six-figure builds have been commissioned for no other reason than to run on this day, only to be retired the next. Lap the course in under a minute and you're quick; in the 55-second range, and you're one of about three cars. The Tsukuba FR production chassis record stands at 55.350 seconds--naturally, this FD was built to go faster.
A built-at-the-last-minute show car this is not; winning in competition demands that every facet of a car compliment and make full use of the rest. Revolution spent months designing just the exterior of the FD, so that once the legendary RE Amemiya started building it, every square inch of 100 percent dry carbon fiber would be made to serve a purpose. Based on a GT300 car, the front bumper features an integrated splitter that limits airflow underneath the car to improve downforce, extends underneath the engine bay to reduce vacuum, and directs oncoming air into a V-mounted radiator and intercooler, all at once. Additional vents in the front bumper direct ambient air toward the brakes, where they're expelled via oversized front fenders that also vent underhood pressure (as does the car's vented hood), as well as allow for a widened wheelbase and lower stance for better lateral stability. Oversized Hankook Ventus RSS R-comp tires and ultra-light Volk RE30s reduce rotational mass while cutting corner weight, all while increasing grip and decreasing rolling resistance. Canards improve turn-in by adding additional downforce up front, while rear downforce is increased by a frame-mounted GT wing, aided by a complex rear diffuser featuring additional canards of its own.
Above the rear diffuser lies this FD's hallmark exterior modification: a one-piece rear end that replaces the rear bumper, hatch, rear glass and quarter panels with dry carbon fiber, matches the front fenders' dimensions, feeds airflow to an ARC differential cooler, and vents excess air from within the rear wheel wells. Carbon fiber construction remains constant in nearly every one of the FD's body panels, save for the roof; the doors have been swapped with lightweight carbon units, and beneath them, carbon side skirts that bridge the increased width of the front and rear fenders, and keep outside air from entering the underside of the car during operation, further decreasing lift. Craft Square replacement side mirrors were added to cut drag, much the same as Aoki-san's choice to replace the stock FD flip-up headlights with streamlined, flush-mount alternatives. Every little bit helps.
Equally intricately engineered is this FD's interior, where the form-follows-function rule was all but written. Aoki-san's first step was to completely gut the FD's interior down to the bare metal, and stitch weld every seam in its unibody to increase overall rigidity. Adding to it, and protecting the car and driver in the event of unforeseen off-track jaunts, is an incredibly complex rollcage that joins the FD's floor, roof, A-, B-, and C-pillars, and extends into the engine bay and trunk to tie in the strut towers, almost completely eliminating body flex. And if doing two jobs at once weren't enough, the cage was further modified to support a trunk-mounted fuel cell, and pressurized AP Racing air-jack system at each corner. Driver interface was limited to only what was needed: a Recaro carbon-Kevlar bucket, MOMO wheel, MoTeC LCD data screen, ECU and telemetry module, and a switch panel. Remember the full carbon replacement hatch? An LCD screen and rear-mounted camera replace the rear-view mirror and glass to allow the driver a view of what's going on behind his machine.
A fully track-prepped interior and exterior could only make sense combined with an equally suited suspension, and with such drastic changes made to the FD thus far, Revolution opted to completely scrap the stock components, and engineer one-off parts specific to their needs. Minding the FD's lower stance, increased girth, and necessary changes to geometry, a custom double wishbone setup was constructed from the ground up, consisting of custom-fabricated adjustable control arms, brackets and rose joints, and custom, CNC-machined replacement hubs that relocate control arm and tie-rod end mounting points for a modified steering radius, lowered stance, and ideal roll center, camber gain and scrub radius. Ultra-stiff Swift springs and custom-valved Revolution dampers keep the chassis elevated, and Project Mu big brakes with 999 race-spec pads round out corner modification for obvious reasons. Nothing was shared about spring rate or damper valving; this car is, after all, still in competition.
For all its radical modification thus far, that the heart of this competition monster remains surprisingly mild might come as a shock to some. Don't let it; posting fast laps has a lot to do with how much power a car produces, but more to do with how readily available it is to the driver. Aoki-san and the Revolution crew knew throttle response and area under the curve were priority number one and peak power number two, so they began by porting the 13B in an undisclosed manner that would flow high amounts of air from their HKS T04Z turbo, but more importantly, develop power predictably at full or partial throttle across a broad RPM range. A Hewland six-speed sequential gearbox was added to allow for full-throttle shifts, to further improve throttle response and decrease lag, and an ATS 1.5-way LSD with a shortened final drive keeps the FD's 13B high in the RPM range, and its wheels firmly planted on the tarmac. Boost is limited to 1.35 bar, to produce just over 540 whp, which, factoring in the car's 960 kg (2,116.4 lbs) weight, gives it the highest power-to-weight ratio of any known FD in competition.
With thousands invested, and their reputation on the line, Aoki-san and the Revolution crew charged the competition in the first event they could. In its shakedown runs at the '08 Tsukuba Super Battle (in rough weather), it completed the circuit in 56.094 seconds--fast enough to beat every other FR machine in competition, and finish Second overall, less than one second off the First Place spot. With the '09 Tsukuba season kicking off, will the Revolution crew be able to improve their FD's time by a mere .744 seconds, to topple a record thought by many to stand for years to come? You know where we're placing our bets!
Mazda FD3S RX-7
Hometown: Land Of The Rising Sun
Occupation: Building, Tuning And Racing Everything Rotary
Hobbies: DDR, Rock Band, Wii Fit, Billy Blanks Instructional Video
Build time: Two Years
Quote: "We are the gods of dance dance revolution!!"
Output: 538 HP
Engine: Garage Revolution cross porting, three-piece apex seals, 50mm exhaust manifold, 80mm front pipe, 80mm full titanium exhaust, custom airbox, custom cooling ducts for turbine; HKS T04Z turbo, GT-2 external wastegate, air filter; ARC V-mounted intercooler and radiator, oil cooler, differential cooler; Trust BOV; NGK plugs; Wako Technical plug wires; Sard FPR; Bosch fuel pumps (2), 850cc/min primary fuel injectors (2), 850cc/min (2) and 800cc/min (2) secondary injectors; MoTeC M2R ECU, boost control solenoid
Drivetrain: Hewland six-speed sequential transmission; ORC triple-plate clutch, lightweight flywheel; ATS carbon 1.5-way limited slip differential; 3.9 final drive
Suspension: Sprint springs 25 kg/mm (front) 16 kg/mm (rear); Revolution racing-spec dampers, custom front and rear double wishbone suspension, front and rear hubs, blade stabilizer, modified strut towers with strengthening bars, relocated steering column
Wheels/Tires: Volk Racing RE30 18x9.5 (front) 18x10.5 (rear) wheels; Hankook Ventus RSS 265/35 (front) 285/30 (rear) tires
Brakes: Revolution custom carbon brake cooling deflectors; Project Mu six-piston calipers and 355mm two-piece rotors (front), four-piston calipers and 332 mm two-piece rotors (rear), 999 brake pads
Exterior: RE Amemiya-built GT dry carbon fiber widebody: Revolution dry carbon fiber front bumper, rear one-piece bumper and quarter panels, front fenders, sideskirts, front and rear canards, rear diffuser, rear hatch, doors, hood and GT Wing; Craft Square dry carbon fiber side mirrors
Interior: Revolution race-spec chromoly roll cage, dry carbon fiber dash, center console, transmission tunnel and floor, custom gear selector and linkage, shift knob, reverse selector; AP Racing air jack kit, brake bias selector, adjustable pedal box; MoTeC LCD Data logger, telemetry module, intercom system, reverse camera and LCD screen; Odyssey lightweight battery.