An endless challenge to "ride".Street best model.
The "Street Sports Suspension Kit" is a height-adjustable kit that pursues the best street ride that we at AutoExe consider.This model was born based on "Dynamic Kansei Engineering" advocated by Takao Kijima, who was involved in the development of numerous sports cars as an authority on suspension while enrolled at Mazda Motor Corporation.Taking full advantage of the integrated design that freely combines the damper and spring, it embodies the depth of ride, not just the absolute performance and the height of the limit.
The damper has a simple structure and uses a fixed damping force type that is advantageous in increasing the damping force from a very low piston speed range of 0.05 m/sec or less, and accurately controls the roll speed from the moment the piston starts moving. The special spring that is combined with it has a spring constant of approximately 110 to 130% of that of mass-produced vehicles, depending on the vehicle model, to moderate the amount of roll. The unique damping ratio (balance between damping force and spring constant), which is the core of the street best, achieves both unambiguous handling and ride comfort that are in sync with the sensibilities of sports-oriented drivers. We have specified the details of ``vehicle height reduction amount,'' ``spring constant,'' and ``damper damping force,'' which are important keys in terms of performance, below, so please use them as a reference. In addition, the lineup of models supervised by Mr. Takashima himself for FR sports cars is named KIJIMA-SPEC.
[Setting the amount of vehicle height reduction]
The lower the vehicle height, the lower the center of gravity of the car, so the kinetic performance will be higher, but it will be necessary to increase the spring constant so that the suspension does not make a full stroke, which will increase the feeling of pushing up = worsen the ride quality.Considering that the ratio of mass-produced vehicles is about -15mm, which is the best in terms of both driving and convenience, it is equipped with a ± 10mm vehicle height adjustment mechanism.
[Setting of spring constant]
Depending on the vehicle model, the spring constant is basically 110 to 130% of that of mass-produced vehicles, and it is a specially shaped product that suppresses roll and provides a comfortable ride. The specifications were determined through repeated driving tests on actual vehicles.
[Damper damping force setting]
The vibration characteristics (movement of the car) can be predicted by calculating the damping ratio (C / Cc), which is the ratio of the damping force (C) of the damper to the critical damping force (Cc). (Detail is,Kijima Seminar §10below)
In general passenger cars, it is set to about 30-40%, but for drivers who actively enjoy driving, this damping ratio is set to about 50%.In addition, the highest priority is given to the rise of damping force in the very low speed range from piston speed 0 to 0.1 m / sec.It slowed down the speed of roll, squat, and nose dive, which could not be compensated by increasing the spring constant, and improved the initial responsiveness of the car.However, if the increased damping force is allocated to the extension side and compression side as it is, the ride quality will deteriorate, so the damping force on the compression side will be lower than that of mass-produced vehicles, and the total damping force will be extended so that it does not change. By adding to the damping force on the side, the balance with handling was maintained.
<Product features>
[High-precision twin tube damper]
By adopting a high-precision twin tube that operates smoothly from a very low speed range, emphasis is placed on rising piston speeds from 0 to 0.1 m / sec.The total damping force is set to 15% + α compared to mass production in order to prioritize kinetic performance, but the damping force on the compression side that causes push-up is lower than that of mass-produced vehicles, and the total damping force that contributes to maneuverability increases so as not to change. By adding to the damping force on the side, the balance of ride quality is maintained.
[Dedicated spring】
Depending on the vehicle model, the spring constant is basically 110 to 130% of that of mass-produced vehicles, and it is a specially shaped product that suppresses roll and provides a comfortable ride. The specifications were determined through repeated driving tests on actual vehicles.
[Full length adjustment type vehicle height adjustment mechanism]
The full-length vehicle height adjustment mechanism that adjusts the vehicle height by changing the length of the shell case allows the vehicle height to be set without changing the damper stroke amount and without being affected by the spring reaction force.Although it depends on the model, we recommend a mass-produced vehicle ratio of -15 to 25 mm, and an adjustment range of about ± 10 mm is provided.
■Some models are normal height adjustment type.
[Utilizing mass production upper mount】
The mass-produced rubber upper mount, which is advantageous in terms of NVH (Noise = noise, Vibration = vibration, Harshness = ride quality), is used as it is.We also consider comfort for passengers.
■The product does not come with an upper mount.
[Street Sports SUS.Kit KIJIMA-SPEC] ... Message from Mr. Kijima
This height-adjustable suspension kit ensures roll rigidity when the rudder is turned on, and it rolls in a jerky manner, enabling firm and stable cornering while maintaining weak understeer.
The roll and yaw generation can be felt linearly, and while it has a firm feel, it is set to a ride that does not have an unpleasant push-up feeling.There are no drastic changes in the specs, but we are confident that it will be the best tuning on the street, releasing the sealed sportiness that the car originally has.I hope that I will run and experience the boiled down ride.
Takao Kijima
He was involved in the development of sports cars as an authority on suspensions at Mazda Motor Corporation, and has served as the development chief of the roadster and RX-7 up to the previous generation.He is currently training the next generation of engineers at Yamaguchi Tokyo University of Science.■Related page:Kijima Seminar
<Overhaul kit>
The overhaul kit is a set of parts necessary for overhauling one street sports suspension kit.The viscosity of the oil is gradually lost due to the mixture of impurities such as iron powder and wear caused by repeated sliding, and the damping force is reduced.It can be refreshed by replacing the damper.
As a guide for replacement, it will run 5 km for 50000 years after installation.
<Product compatibility table>
■ Street Sports SUS.Kit KIJIMA-SPEC Full length adjustment type twin tube damping force fixed type 1 set ※ 1
| Car name | 適合 車 種 | part number | Tax-included price (Price without tax) | Spring constant (Unit N / mm) | Vehicle height adjustment range (mm) (Recommended vehicle height) | Codes | Reference work Time |
|---|---|---|---|---|---|---|---|
| RX-8 | SE3P | MSE7850 | ¥ 203,500 (¥ 185,000) | F: 38.2 R: 29.4 | Before MC: -5 ~ -20 After MC: -10 to -25 (F: -15 R: -15) | D | 2.5h |
| RX-7 | FD3S | MFD7850 | ¥ 203,500 (¥ 185,000) | F: 56.2 R: 43.7 | ± 0 to -5 ※ 2 (F: -5 R: -5) | D | 2.5h |
| Roadster | NDERE/NDERC ND5RE/ND5RC NCEC All NB series cars | MND7860 MND7850 MNC7850 MNB7850 | ¥ 203,500 (¥ 185,000) | F: 37.2 R: 22.5 F: 24.5 R: 12.7 F: 27.4 R: 23.5 F: 32.3 R: 23.5 | -5 to -25 (F: -15 R: -15) | D | 2.7h 2.7h 2.5h 2.5h |
※ 1 The product does not include an upper mount.Use the genuine upper mount as it is.
※ 2 Measured value when Spirit R grade is installed.
■ Street Sports SUS.Kit Vehicle height adjustable twin tube Fixed damping force set for one ※ 1
| Car name | 適合 車 種 | part number | Tax-included price (Price without tax) | Spring constant (Unit N / mm) | Vehicle height adjustment range (mm) (Recommended vehicle height) | Codes | Reference work Time |
|---|---|---|---|---|---|---|---|
| MAZDA2 / Demio | DJ 2WD car * 2 * 3 * 4 DJ 4WD car * 2 * 3 * 4 | MDJ7850 MDJ7860 | ¥ 200,200 (¥ 182,000) | F: 26.5 R: 26.5 F: 23.5 R: 43.1 | -5 to -25 (F: -15 R: -15) | D | 2.1h 2.5h |
| MAZDA3 | BP system * 2 * 3 | MBP7850 | ¥ 200,200 (¥ 182,000) | F: 31.4 R: 46.1 | -5 to -25 Gasoline 1.5L car: -5 to -20 (F: -15 R: -15) | D | 3.2h |
| MAZDA6 / Atenza | All GJ series cars ※ 2 | MGJ7850 | ¥ 225,500 (¥ 205,000) | F: 32.5 R: 42.7 | Diesel: -5 ~ -25 Gasoline: -5 to -20 (F: -15 R: -15) | D | 2.9h |
| CX-30 | DM system * 2 * 3 | MDM7850 | ¥ 200,200 (¥ 182,000) | F: 34.3 R: 49.0 | -10 to -30 (F: -20 R: -20) | D | 3.2h |
| MX-30 | DREJ3R/DREJ3P * 2 * 3 | MDM7850 | ¥ 200,200 (¥ 182,000) | F: 34.3 R: 49.0 | -10 to -30 (F: -20 R: -20) | D | 3.2h |
| CX-5 | KF2P/KF5P* 2 * 3 * 5 | MKF7850 | ¥ 225,500 (¥ 205,000) | F: 36.6 R: 46.1 | Diesel vehicles: -15 to -35 Gasoline 2.5L car: -15 to -30 (F: -25 R: -25) | D | 2.9h |
| CX-60 | KH3R3P/KH3P * 3 * 6 | KHA1 V5 700A | ¥ 247,500 (¥ 225,000) | F: 56.8 R: 55.9 | -15 to -35 (F: -25 R: -25) | D | 2.8h |
| CX-8 | All KG series cars * 2 * 3 | MKG7850 | ¥ 225,500 (¥ 205,000) | F: 32.3 R: 66.6 | -15 to -35 (F: -25 R: -25) | D | 2.9h |
※ 1 The product does not include an upper mount.Use the genuine upper mount as it is.
※ 2 Functionally, it is not necessary to install the adjustable stabilizer link (part number: MDE7605 / MBP7605 / MKE7605 / MMJ7605) at the same time.
※ 3 When installed in a car with a 360 ° view monitor, it may be necessary to adjust the aiming of the camera.
※ 4 MAZDA2に装着する場合、純正マウンティングラバー(DA6A-28-380)×2、純正バンプストッパー(DA6A-28-1A0A)×2が別途必要。
※ 5 When installing on KF series-300001 ~, genuine mounting rubber (TK52-28-380B) x 2 is required separately.
■6 Currently being confirmed as compatible with KH series 200001~.
■ Club Sports SUS.Kit
A high-limit sports model with a low center of gravity and high roll rigidity.
Uses a monotube damper for high load areas in winding and circuits.The spring constant is 200% or more for mass production.The standard vehicle height is -30mm.Low center of gravity and high roll rigidity with reduced comfort. >> More details
