The Tokyo Bay Aqualine is probably one of the most ambitious and expensive projects that has ever been undertaken by the Japanese, taking a total of 31 years to complete at an astronomical cost of $11 billion. It connects Kawasaki-city to the Chiba peninsula, taking drivers from the chaotic, bustling metropolitan area to the sticks in about 15 minutes. This tunnel/bridge combination is a godsend for car enthusiasts, allowing them to escape the stressful city traffic and find a few empty country roads to enjoy their cars on. This is precisely where we met up with Yoshi, the owner of this clean FC35 RX-7.
Yoshi is pretty much the definition of a car nut. Growing up close to some of the best driving areas that Hakone and Fuji have to offer, he has been fine-tuning his driving skills since he first got his license. This fanatical obsession with cars has led to a career working for one of Japan’s biggest car manufacturers (we can tell you it’s not Mazda), part of a team that has created key models we’re familiar with. So after a hard week’s work planning future vehicles, Yoshi likes to relax by driving his impressive collection of sports cars around his favorite mountain roads. But it isn’t expensive exotics he’s into, rather highly modified iconic Japanese models we all know and love. Over the last three years, he has created what has quickly become his favorite car, an old FC3S RX-7 that, although street legal, is bordering on full time attack spec.
On an early Sunday morning, there’s absolutely nothing that disturbs the tranquil surroundings of the Chiba countryside, until a flock of birds franticly take to the sky as an unnatural concoction of mechanical noises thunders through the hills. The 13B has been built by Prestige, a rotary specialist in Kyushu, and tuned for a savage power delivery, achieved by bridge-porting the intake section of the rotor housings. This gives it that unmistakable lumpy idle and a very distinct buzz at higher engine revolutions. Providing the forced induction is a Garrett T04R mounted on custom-built headers, and spent gases are dumped through a one-off exhaust. The triple core Trust intercooler helps cool the 22 psi of compressed intake charge, which is then channeled into the engine via a modified Trust inlet pipe and FD3S intake manifold. Fueling is handled by four Sard 1,000-cc/min injectors, which are kept topped up by the modified BNR32 in-tank fuel pump. Top Fuel Racing took care of the engine mapping, fitting and programming the F-Con V Pro ECU, resulting in 500 hp at 8000 rpm with almost instant boost response at anywhere above 3000 rpm.
Highly modified rotaries are known for overheating quickly, and Yoshi’s car isn’t any different. To keep this under control, a secondary FC3S stock oil cooler was fitted along with a triple core radiator. One small but necessary item is the HPI engine damper, which keeps the engine (along with the much stiffer MazdaSpeed mounts) from rocking too much when left to its intermittent pulses at idle. The ATS twin plate carbon clutch is mated to a lightweight flywheel to help reduce rotational masses, while the stock differential has been thrown out and replaced with a MazdaSpeed LSD, along with a shorter FD3S 4.3 final drive. Shortening the gears makes Yoshi’s RX-7 especially suited to tight mountain roads, where this car spends most of its time.
It’s actually pretty interesting how the eye-catching orange coloring came to be. A few years ago, Yoshi had a little incident on a very wet highway where the lightweight FC hydroplaned out of control. Most of the stock then gunmetal exterior got damaged, which for Yoshi, turned out to be the perfect opportunity to transform the looks. So on top of stripping the car down and fitting a full rollcage, the sills were spot-welded and injected with expanding foam to help stiffen up the aging shell.
But it didn’t end there. Autoexe member stiffening bars were added underneath the car, as well as a rare part Yoshi was especially happy with: Nagisa Auto Gacchiri supports. These are triangular stiffening bars added onto the chassis, underneath the front fenders to reinforce the front end and give more precise steering. A JIC carbon strut bar completes the front bracing upgrades while to firm up the rear end a Cusco strut bar was also added. Since a lot of the body panels needed replacing after the unexpected spin on the highway, Yoshi went for a Foresight front bumper, wider fenders and an aero hood. Pan Speed aero mirrors and an intake headlight cover are the final touches before the car was painted in the same orange as used on the Porsche 997 GT3 RS, for that true Club Sport feel. To keep the exterior clean, no big GT-wing is used. Instead, an RE-Amemiya carbon diffuser helps keep the rear end stable at speed. Up front Yoshi fitted a custom under-spoiler, fixed in position with metal lines. Gunmetal 17-inch Advan RS wrapped in 255/40R17 Toyo R1R tires help seal the time attack look to perfection.
The RX-7 sits low thanks to very stiff PCR custom set-up suspension, while braking is handled by large Endless 6-pot calipers at the front and larger diameter discs all around. There’s very little out there that can keep up with Yoshi and this car through tight mountain roads he’s now at one with his machine, able to extract its fullest potential. It is, as he puts it, Perfect! Functionality rules in the interior with a series of dash-mounted Defi gauges, electronically managed by the trick Defi Control Unit II. Knight Sports speedometer helps Yoshi tell when he accidently goes over the tight Japanese speed limits, while he sits comfortably strapped down in the Cobra bucket seats by the green Takata belts. The passenger side gets a slightly more comfortable FD3S bucket seat. Probably the least used addition in the interior is the audio system, there from a previous owner, something that just can’t be heard over the bridge-ported concerto.
Yoshi has covered a total of 10,000 miles or so with his current engine, but it’s in such an extreme state of tune that it will soon get replaced with a fresher motor, as 16,000 miles is pretty much as long as they can stay reliable for. This is his seventh engine, and the replacement is already sitting in his garage, a Dandy-built unit fitted with a Trust T88 turbine that was originally a back-up engine for their Bonneville Speed Trial RX7. Obviously, 500 hp isn’t enough anymore.
Specs & Details
'89 FC35 RX-7
Engine Bridge-ported 13B; MazdaSpeed engine mounts; HPI engine damper, air filter; custom-made T04R turbocharger; HKS external wastegate, F-Con V Pro ECU; custom-made exhaust system; custom intercooler piping; Trust triple core intercooler; FD3S intake manifold; BNR32 GT-R modified fuel pump; Sard FPR, 1,000cc injectors (x4); NGK Power Cable ignition leads, platinum plugs; Twin layer radiator, FC3S oil cooler setup
Transmission ATS twin plate carbon clutch & lightweight flywheel; MazdaSpeed transmission mounts & LSD; Mazda FD3S 4.3 final drive
Suspension & Brakes PCR custom set-up suspension kit; JIC carbon front strut tower bar w/ custom bracing; Cusco rear strut tower bar; Autoexe member brace; Nagisa Auto Gacchiri supports; Endless 6-pot front calipers & 324mm 2-piece slotted discs; stock 2-pot rear calipers & 315mm oversized discs; rear caliper offset adapter; FD3S master cylinder
Interior Custom 9-point rollcage; Cobra driver side bucket seat; Takata harness; Mazda FD3S passenger-side bucket seat; Momo steering wheel; Night Sports combination meters; Mazdaspeed shift knob; Defi gauges (water temperature, oil temperature, oil pressure), control unit II; Trust boost controller; relocated battery
Wheels & Tires Advan Racing RS 9Jx17" +22 (f/r); Toyo R1R 255/40R17 (f/r)
Exterior Foresight front bumper, wide front fenders (+30 mm); custom front under diffuser; Aero hood; RE Amemiya carbon rear diffuser; Aero mirrors; Porsche 997 GT3 RS orange paint