We all have our own perception of time-the unique awareness shaped by the events that have taken place throughout our lives. What time means to us and how we use it helps form who we are. Every action has a different duration. Each action compares to another in sequence, distancing the past from the future. No matter how many ways you dissect it time defines us. This line of thinking can be applied to building cars and this Circuit-proven FD Mazda RX7.
We all share time, well, the concept anyway. While we may not all get the same amount, it is how we use what we are given that makes us who we are. Those who value time typically use what they have to create something meaningful. Tangible or not, what they produce can make a remarkable impact on both their own lives and the lives of others. These people, who realize the importance of each second as it passes, are in a constant search of finding more. It is with this same concept in mind that Yukimitsu Hara has taken to building one of the most prevalent, grassroots Time-Attack FD Mazda RX7 to date.
The name Time-Attack, in itself, defines the sport. Time-Attack is an all-out assault against the clock. With no parameters and no directives, you enter the circuit with the solitary objective of achieving the fastest time you can manage. The main appeal of this ever-growing motorsport is the opportunity to test you in a way offered by few others. It's the opportunity to push you to the limit, both physically and mentally, constantly balancing you on the thin line of risk and reward. Even if you haven't felt this personally, you can understand it by talking to Hara-san about the way he describes each and every piece of his Mazda RX7. It is a machine that he understands fully; it has become an extension of his body.
Hara's love for cars started early on in his life. Stemming from a strong influence from his father, he began to take interest in cars at just 5 years old. Thirty-five years later he still finds himself surrounded by the automotive lifestyle. Having owned a variety of cars ranging from an RX7 and 180SX to a Miata, Skyline, and even a Chevrolet Suburban at one point, he was no stranger to different platforms. Visiting the circuit regularly with each car he owned for open track days and competitions, his love for Time-Attack grew. Five years ago, he eventually came back to the FD Mazda RX7 and its unique rotary engine. This time around, however, Hara wanted to build a FD that would be unique enough to make an impact; more importantly though, he set his sights on breaking the 1-minute mark at Tsukuba Circuit's TC2000.
Hara's daily commute takes him from Nakano-ku where he lives, to Car Shop Glow in the Nerima ward of Tokyo. Hara is a director for Car Shop Glow, which specializes in highly customized exterior and interior lighting of a wide variety of cars, though favoring luxury European models. With that in mind, it stands to reason that most people would mistake Car Shop Glow for a tuning shop after seeing Hara's RX7. They would be just that though. Much of the actual work that gets put into his car actually takes place at Zest Racing, a tuning shop in the Misato area.
To achieve his goal of a sub 1-minute lap at TC2000, Hara took to the drawing board starting with the heart of the car: the 13B. Mr. Motizuki of Mocchi Racing was put in charge of the engine overhaul. Starting with a full bridge port and DLC coating of the block, the rotors were then replaced by their FC counterparts, effectively lowering the compression of the engine, allowing Hara to safely run much higher levels of boost. He takes full advantage using the massive Trust T88-34D turbocharger that's used to propel the 19 pounds of boost through a custom 90mm titanium exhaust setup to the tune of 530 hp and 361 lb-ft of torque. This is the most power the car has ever made, working his way up from a T04E turbo, to a TD07S-25G, and now the latest revision with the T88. Hara says that with each boost up he gets progressively quicker, as long as he is able to manage the higher RX7 boost level exiting corners.
Now that the engine is at a level that he feels is satisfactory, Hara is looking for other ways to find time on track, like lightening the car more and experimenting with other aerodynamic options. Aside from the RE-Amemiya GT-AD body kit, the car employs an extravagant frontend aero option consisting of carbon canards and splitter. Mr. Yamazaki at Zest Racing made both custom pieces. Discussing aerodynamics with both Hara and Yamazaki is very interesting; they both agree that frontend downforce plays a major role in improving lap times.
This may be a good time to point out that Hara's RX7 is still street registered (it even has an ETC unit to pay road tolls in Japan). One of his goals was to have a car that maintained a somewhat street feel but would still be fast on circuit. Specifically, he retained the car's audio system and amenities such as air conditioning without using special parts like a sequential gearbox. This is why the transmission is a traditional five-speed built by OS Giken. An ATS carbon clutch and Mazdaspeed two-way differential get the power to the ground.
Aragosta coilovers with 16k Hyperco springs settle out each end of the Mazda RX7 as Hara weaves his way through each of the corners of Tsukuba. A full array of Super Now suspension arms holds the custom alignment settings in place. Interestingly enough, behind the 18-inch Volk CE-28's (TE37SL's for circuit), you won't find any upgraded brakes. Hara believes it's important to keep the OEM braking for more stability during corner entry. He says that it's important for him to not upset the car's balance in braking, and an increased bias will do just that. This is just one more detail in his personal driving preferences that he's realized will allow him to shave off more time on track.
There is one common theme that circulates around Hara's RX7 build, which consists of each modification thought out in advance, or as a result of on-track testing. Every change, every alteration, was done with the sole purpose of finding more time. In his own words, a build that is "never ending" will always manage to become quicker. He has successfully translated his passion into speed. He has long since shattered his goal of a 1-minute lap at TC2000 with a recent personal best of 56.4 seconds. He shows no sign of slowing down, however, with a new goal set in the 55-second range. This is how time has molded him and how it has defined who he is. He is, in fact, making the impact he hoped.
Behind the Build
Representative Director at Car Shop Glow
Time Attack and Competition racing
Running under 1 minute at Tsukuba
1996 Mazda RX-7 (FD3S)
530 hp/360 lb-ft of torque
Engine Mocchi Racing-built 13B, FC rotors, side face bridge port, DLC coating, Trust T88-34D Turbocharger, Trust manifold, Trust wastegate, HKS Power Flow intake, HPI Intercooler with custom Zest Racing piping, Ron Davis radiator, Samco hoses, BNR34 fuel pump, Sard 1,000cc injectors, Sard fuel rail, NGK spark plugs/wires, Yume Koubou titanium exhaust, HKS V-Pro 3.3, A'PEXi Power FC
Drivetrain OS Giken five-speed transmission, Super Now transmission mounts, RE-Amemiya quick shifter, ATS Carbon clutch, ATS flywheel, Zest Racing-spec Mazdaspeed two-way differential
Suspension Aragosta coilovers, Hyperco springs (16k), Super Now adjustable control arms (all arms), Mazdaspeed strut bar
Wheels/Tires Circuit: 18x10.5/11 +18 (+22mm spacer, front) Rays TE-37SL with 295/30/18 Yokohama Advan A050; street: Rays CE-28, Advan TCIII
Brakes OEM calipers/rotors, PFC carbon pads
Exterior RE-Amemiya GT-AD body kit with one-off 40mm wide front fenders, Voltex 1,700mm rear wing, FRP doors and hatch, RE-Amemiya headlights, custom Car Shop Glow Brown Pearl paint
Interior Recaro TS-G seat; OMP steering wheel; RE-Amemiya shift knob; HKS Circuit Attack Counter; A'PEXi Power FC and boost/oil temp/oil pressure gauges; Zest Racing rollcage and carbon door cards; Carrozeria head unit and amp; Kicker front speakers; ETC unit
Gratitude Zest Racing, Kemitec, Car Shop Glow, Sunoco, Super Now