How often do you hear the word ‘balance’ thrown around when people talk about car tuning? Often you see modified cars roaming the streets with tremendously powerful engines, yet other areas of the car go untouched and more often than not, these areas are usually the brakes, cooling ancillaries or even the driveline. Granted, factory parts are usually able to take decent power increases before failing, yet are they up to the standard of the other parts that have been upgraded in order to maintain good balance?
Well ‘balance’ is exactly what SuperAutobacs at Sunshine Wharf in Kobe have achieved with their FD3S Mazda RX-7 demo car. The most hardcore of three demo cars built by the Kobe branch, the FD3S’s most interesting feature is the fact that it has been tuned for maximum speed, while still being able to pass the notorious Japanese ‘shaken’ (vehicle roadworthy inspection). All parts are sold through SuperAutobacs various suppliers including RE Amemiya, TTperformance, RAYS and ARC so you could literally drive your own FD3S into SuperAutobacs Sunshine Kobe and ask for it to be modified in exactly the same way. Having said that, the components used to modify this RX-7 are only the best and the total engine and driveline tuning package weighs in at a hefty 1,380,150 yen, you can almost double that price if you want your FD3S to look like the SuperAutobacs RX-7 demo car…
Upon arriving at SuperAutobacs early one morning with Atsuko-chan (this months Kansai model) we were greeted by Takeda-san, with whom we organized our photo shoot and without waiting he led us to their prized Mazda. The first things that strike you when seeing the SuperAB RX-7 are the RE Amemiya GT-AD aero kit incorporating the renowned RE Amemiya AD FACER N1 front bumper and matching UNDER SWEEP front splitter. This kit has to be the undisputed champion of FD3S RX-7 body kits, as just about every issue of Option2 magazine has at least one photo of an RX-7 on a circuit with one. That shouldn’t detract from this cars ability to stand out, what with the almost ‘Nissan Bayside Blue’ like hue, the RAYS G-Games 77W wheels in gunmetal and the Voltex Type I GT wing. We can’t forget the RE Amemiya AD Hood-9 in wet carbon (painted), CRAFT Company rear carbon diffuser and the full carbon Ganador super mirrors which round out what is in my opinion, the best looking FD3S body kit to date. I would run out and buy the GT-AD kit today… only I don’t have an FD3S or the 276,000 yen lying around to buy it!
On the inside, components have been chosen to complement each other as carefully as the outside. The bright red RECARO SP/G seats grab your attention first and I can tell you from experience that they’re not easy to get into, but when you’re seated they provide excellent support… as should be expected. Actually, Atsuko gave the RECARO seats the thumbs down as she thought that they weren’t worth the trouble it took to get into them! She might change her mind after she’s experienced a flying lap at Central Circuit though. The Personal Competizione suede 350mm steering wheel complements the seats very well, as does the FEED heavyweight shift knob. TRUST/Greddy ‘SM Integrate’ meters incorporating Oil temp, Water temp and Fuel pressure as well as the obligatory boost gauge, letting the driver know what the HKS EVC 4 boost controller is doing. The fuel pressure gauge and the HKS EVC 4 are housed in a custom carbon-look plate that occupies the 2 DIN space where the audio unit should be. Finally a set of contrasting green TAKATA 4-point racing harnesses complete what is a nicely upgraded interior which isn’t overdone or lacking in any one area.
Earlier I mentioned the rather large price tag associated with the engine and driveline package, which ‘might’ seem reasonable if you factor in a new brand name turbo kit… which unfortunately this car doesn’t have! That’s right the SuperAutobacs Sunshine Kobe FD3S demo car still sports the factory twin turbo setup, which puts out 360ps at 0.9 bar boost and a respectable 42.3 kg/m peak torque figure which is up 10.3 kg/m from factory. Engine management has been upgraded with an HKS F-Con SA sub-computer with aftermarket digital display, which SuperAutobacs specialize in. HKS engine management systems seem to be more popular in Japan than A’pex, which might come as a surprise to some due to the popularity of Apex engine management systems overseas. Looking at the rest of the hardware, standard injectors and fuel pump are able to carry out their duties without too much trouble at the present power level, as do the engine internals. The spark plugs and spark plug cords have been swapped for NGK Racing items and a ‘Street Life’ static earthing system has been installed. HKS air filters with an HKS racing suction piping kit take care of the intake side of things and the hot boosted air is cooled by a full ARC intercooler kit complemented by a TRUST twin oil cooler kit. Engine temperatures are kept at decent levels by a ‘one off’ F-Win 3 core aluminum radiator. Waste gasses pass trough a standard exhaust manifold, RE Amemiya Power Expander EX front pipe, Knight Sports METALIT Pro catalytic converter and out into atmosphere through an RE Amemiya Dolphin Tail titanium muffler. As far as the engine goes, you could conclude that it has been upgraded to ‘mild circuit spec’, not overly powerful, yet balanced enough to net some impressive times at TI Circuit in Okayama prefecture, but I’ll go into that later.
The driveline in the FD3S is what you’d expect from a circuit driven sports car. Starting at the engine with an EXEDY Hyper semi-carbon multi plate clutch with a FEED ‘Big Release’ clutch pedal slave cylinder to make the clutch pedal easier on the left leg… in fact, if I hadn’t have known better, I would’ve thought it was the standard clutch. The standard 5-speed gearbox sends power back to a KAAZ Power Pot Basic 1.5 way LSD, which is held up by Mazdaspeed Diff mounting bushes. The modifications made to the driveline are almost bulletproof for handling 360ps, but as SuperAutobacs Sunshine Kobe say, “There is no end to the challenge of RX-7 tuning” so we might see this car with a lot more power to take advantage of the upgraded driveline in the not too distant future.
Lastly we have what the Japanese sometimes refer to as ‘footwork’, or suspension, brakes and wheels to you and me. What is possibly this cars most expensive single modification, other than the wheels and tires, is the TTperformance ‘Special Version’ fully adjustable coil over suspension kit. Based on Apex N1 adjustable dampers, TTperformance have used their own spring rates and bump and rebound settings to produce a set of coil over suspension which is comfortable enough for the street, while also allowing higher cornering speeds and greater traction on the circuit. Moving down to the brakes, genuine Mazda RX-7 ‘Spirit R’ 4-pot calipers have been used aswell as Project Mu SCR-Pro (313mm slotted front / 314mm slotted rear) brake rotors with Sumitomo SEI Type CS brake pads. This setup is marketed as a reasonable alternative to the ultra expensive caliper and brake disk sets from Endless, Project Mu and others. The RAYS G-Games 77W (19×9.0JJ front, 19×10.0JJ rear) wheels in gunmetal look fantastic against the medium blue paint and fill out the wide RE Amemiya guards beautifully. The wheels are wrapped in Yokohama ADVAN DNA GP 19 inch rubber.
So how does the SuperAutobacs RX-7 perform? Well Matsuura-san the Sports department Manager kindly allowed me to drive the FD3S around the streets surrounding Sunshine Wharf and although I didn’t get much past 70km/h, the car obviously had very good low range boost response due to the standard turbo setup. The car felt very agile even at sub-60km/h speeds, and the only way I can describe the brakes is ‘reassuring’ and I might mention again the weight of the clutch was almost normal thanks to the FEED Big Release slave cylinder. I’ve always had a soft spot for the FD3S RX-7, and today’s drive only reinforced to me what a brilliant sports car (with lots of potential) it is. The SuperAutobacs Sunshine Kobe RX-7 has also proven itself on the circuit posting a fastest lap time of 1:40.972 at Ti Circuit in Okayama prefecture. In the Circuit Challenge 2004 race at Ti, the FD3S came 2nd in class and posted a 1:47.231 lap time on a wet track in mock race conditions. It’s fair to say that the SuperAutobacs Sunshine Kobe RX-7 is more than just a demo car, it’s a track proven, roadworthy and street driven circuit racer.
Car: FD3S Mazda RX-7
Engine: 13B-REW Rotary twin turbo
Standard 13B-REW, standard twin turbo, HKS Racing Suction kit, Mazdaspeed engine mounts, HKS F-Con SA sub-computer, standard injectors, standard fuel pump, HKS EVC 4 boost controller (0.9bar), F-Win aluminum 3-core radiator, ARC full intercooler kit, Trust twin oil cooler kit, NGK sparkplug cords, NGK Racing sparkplugs, Street Life earthing system.
Standard 5-speed gearbox, Exedy Hyper multi plate semi-carbon clutch, FEED Big Release clutch slave cylinder, Kaaz Power Pot basic 1.5-way LSD, Mazdaspeed diff mounting bushes.
RE Amemiya AD-GT kit, RE Amemiya AD Facer N1 front bumper, RE Amemiya Under Sweep front splitter, RE Amemiya AD Hood-9 carbon bonnet, Voltex Type I GT Wing, Craft Company rear carbon diffuser, Ganador Super carbon mirrors.
Suspension and Braking Tune:
TTperformance fully adjustable coil over suspension, Mazda Spirit R 4-pot calipers, Project Mu 313/314mm slotted brake rotors, Sumitomo SEI Type CS brake pads, RE Amemiya stainless steel brake hoses.
Wheel and Tire Tune:
RAYS G-Games 77W (19×9.0JJ front, 19×10.0JJ rear) in gunmetal, Yokohama ADVAN DNA GP (235/35/ZR19 front, 265/30/ZR19 rear).
Yusuke Takeda and Kenji Matsuura at SuperAutobacs Sunshine Kobe for taking time out of the busy schedule to help me photograph the car and allowing me to drive it. Thanks guys!
Text and Photos: Justin Karow