To refine the transient characteristics. AutoExe style tuning method.
What is Kansei Tuning in Suspension?It is that the car and the driver synchronize and interact.Specifically, it is the refinement of the transient characteristics that the car responds to the driving operation.For example, the moment you start turning the steering wheel, the car gently starts rolling with a G.Then, while maintaining a stable posture, the car traces the line envisioned by the driver's accelerator work ... Bringing that process to "A New Driving Sensation", which is a sporty driving that could not be experienced at the level of mass-produced cars. ..Let's explain step by step the AutoExe style tuning method that realizes this ride.

We judge driving, comfort, and safety on the street from various angles, and set a standard of about -20 mm for mass production specifications for sports cars and about -25 mm for SUVs with a high center of gravity.It is different from the short-circuit tuning that the lower the better.
Next, once the amount of vehicle height reduction is determined, the minimum required spring constant can be derived based on the car's sprung mass (weight). Our objective is to obtain maneuverability that is in sync with the driver's expectations, but the basic setting is to not sacrifice ride comfort in urban areas. Therefore, although it depends on the car model, the spring constant is determined based on approximately 110% of the mass-produced car. In combination with the damper damping force, the ride quality and maneuverability are exquisitely set. However, high-limit sports products designed for circuit driving and club sports suspension kits are an exception. Here, we are trying to achieve a 250% level, giving priority to maneuverability = roll rigidity, while abandoning the need for both ride comfort and ride comfort.

[Damper damping force setting]
The function required of the damper is to convert the vibration energy of the spring set in the previous section into heat energy and attenuate it. Only the core part of the "ride taste" has its own attention to detail in its characteristics.

Please see the above <Damping ratio / damping force characteristic diagram>.You can see that the emphasis is on the rise of damping force in the low speed range, especially in the very low speed range that affects the initial roll rigidity ().Blue line).Regardless of the series, our dampers are designed with the highest priority on rising in the very low speed range from 0 to 0.1 m / sec piston speed.
Why are you so particular about the very low speed range?Generally, the damping force of the damper is displayed as a numerical value at 0.3 m / sec, but it is the area below that that smoothly accommodates the initial roll that occurs at the entrance of a corner or turning back at S. be.Specifically, the moment when the damper starts to move.Numerically, by raising the damping force with a sharp curve from a very low speed range with a piston speed of 0.05 m / sec or less, the roll speed from the moment the steering is turned is suppressed (not the absolute amount of roll).By lowering the angle (deg / sec) per hour when the car = driver tilts, the fear of rolling at once is reduced.The car is rolled gently and gently, increasing the sense of security when cornering.On the other hand, the fact that the increase in damping force is suppressed after 0.1 m / sec, which is required for energy absorption when overcoming protrusions such as ruts, manholes, and road seams, is a reduction in push-up that resonates in the abdomen (feeling of riding comfort). ).Also, for the same reason, the allocation of the total damping force value is piled up on the extension side and the compression side is kept low ().Blue line).And the damping ratio is the key to the design.※ 1Unique design philosophy based on.In all products, not the single specifications of dampers and springs, but the ideal value as much as possible with the combination of both.※ 2The point is to get closer to (Red line).

By the way, we have an ideal curve that shows the absolute value of the damping force (Blue line) Has been called the "sunfish curve".This is because the damping force on the extension side rises sharply and resembles the head of a fish sunfish.The same thing was seen with the concept of damping ratio (an index of spring difficulty in movement).Red line)is.You can see that the damper is designed to work more effectively (high damping ratio) when the piston speed is low.In terms of form, "Chinese Ankou Curve" ... I would like to introduce it for an image-like understanding of our concept.

With this design concept in common, the technical methods and specifications are clearly separated to establish the "ride" of each lineup.As for the suspension, other parts are set in detail.For example, a wide range of sports stabilizers, from sports cars to passenger cars.This is a manifestation of our sensitivity tuning, which suppresses roll and stabilizes posture without increasing the spring constant more than necessary.Furthermore, adjustable links, tie rod ends, etc ... I want you to go beyond the mass production level and realize a sure footwork suitable for the rider's sensibility and hobby.