Bitche Original " All children are born knowing it. Only a few still remember it when they grow up. Only one car company has never forgotten it. In the language of adults, it is used to express the pleasure and release brought by extreme dynamics. However, in fact, only children really understand it. They simply say it. :"Go Zoom-Zoom." And we practice it every day. That's why we can build the car that's in front of you right now. Zoom-Zoom! Today we're taking it from you Are you awakening in your heart?" This passage is quoted from the title page of the Mazda MX-5 owner's manual. So what is Zoom-Zoom? Today, I will take my own MX-5 as an example. Through chassis analysis, I will take you to understand the spiritual essence of Mazda Zoom-Zoom.

· Static introduction

My MX-5 is a parallel imported Mogui 2018 2.0MT i Sport version. Model code: ND5C. Different from the MX-5 RF (NDERC) introduced on the official website, the two biggest differences are that first, it is equipped with a 6-speed manual transmission, and second, it adopts a soft-top convertible structure.

In terms of appearance, compared with the first three generations of MX-5 The cute and cute image and the fierce "little eyes" of ND always remind me of Angry Birds. The expanded front and rear fenders give it the visual effect of a naturally wide body. The vehicle's shape does not have too many complex hard-line designs, but instead uses curved surfaces bent by soft lines to create a powerful body shape, fully interpreting the core concept of soul-moving design, less is more.

The long front end, short front overhang, long wheelbase, and the cockpit close to the rear wheels, these design features fully demonstrate the temperament of the Roadster model. Compared with the RF version, the soft-top version can completely store the roof into the body, and the body lines will be more chic and elegant after the roof is opened.

It is worth mentioning that the soft top of the MX-5 has been opened and closed manually from the first generation model to the present. The roof structure is simple and light. There is no complicated electric mechanism. The opening and closing action of the roof does not take more than 3 seconds. It is not restricted by the vehicle speed. You can enjoy the blue sky, white clouds and gentle breeze anytime and anywhere. This is why the MX-5 has been selling well for more than 30 years. One of the unique secrets.

Entering the car, don’t have too many expectations for the MX-5. The interior materials are all hard plastic. After all, it is The price in North America is about the same as Angkesela. Fortunately, Mazda's designers used all the limited budget on the knifeOn the blade, texture quality aside, the design and layout of this interior are still very online, complementing the appearance.

· Power system

< span style="text-indent: 2em;">In terms of power, the MX-5 ND is equipped with a 2.0L Chuangchi Blue Sky engine with a maximum power of 116kW and a maximum torque of 200N·m. It adopts a front-mid layout and rear-wheel drive. Note that this is a front-mid layout, not a front-mounted layout, because the front section of the MX-5's engine almost overlaps the front axle of the vehicle, and the engine mass center is located behind the front axle, so strictly speaking it is a rare front-mid layout. . Models that also have this type of layout include Honda S2000, Mercedes-Benz SLR, Dodge Viper, Corvette, etc.

The engine is equipped with a 6-speed manual transmission. This transmission, codenamed M66M-D, is a brand-new product specially developed for ND. Next, let’s briefly talk about the design features of this gearbox. The reason why the NC manual gearbox is not used is due to lightweight considerations. The entire transmission system of ND weighs only 82kg. This gearbox concentrates all the shift forks and synchronizers that are conventionally distributed on the main shaft and countershaft on the main shaft, simplifying the structure and reducing the size of the gearbox.

In addition, this gearbox does not have an overdrive gear, and the highest gear ratio is 1:1, which is a direct gear. After the engine power is directly engaged by the input shaft and the output shaft, it is delivered to the rear differential through the rotating shaft. This not only improves the power response, but also reduces the number of transmission gears and reduces the weight.

Another advantage of this design is that it eliminates the shift reversal mechanism of the 6-speed gearbox. Since we are now accustomed to odd-numbered gears (1/3/5 (Shift) Push the handle forward to engage the gear, and move the lower end of the handle backward. The opposite is true for even-speed gears (2/4/6 gears), but due to the gear arrangement of the longitudinal 6-speed manual transmission, the synchronizer needs to move forward to enter the corresponding odd-numbered gear, so a setting is required between the gear handle and the gearbox. A reversing mechanism is required to accomplish this. However, the 6th gear of the MX-5 gearbox does not have a transmission gear, so the gear arrangement is the same as that of the 5-speed gearbox. Therefore, this reversing mechanism can be omitted, further simplifying the structure, reducing weight, and also having a more direct shifting feel.

·Chassis structure

As the saying goes, "It would be better to be 10 kilograms lighter than 10 horsepower", lightweight design is implemented in the entire MX-5. The curb weight of the soft-top manual version is only 1058kg, and the Japanese standard 1.5 version is as low as 990kg. In order to reduce the weight of the vehicle while maintaining rigidity, the MX5 ND uses a large number of high-strength steel and aluminum alloys above 780Mpa. Except for the rear fenders, all body panels are made of aluminum alloy. Suspension links, steering knuckles,The engine lower guard, chassis structural parts, front and rear anti-collision beams, and roll cage assembly are also made of aluminum alloy.

There are two reinforcements in the middle of the chassis, both of which are made of aluminum alloy. The reinforcements issued to the gearbox are exclusive accessories for the manual transmission version. The automatic transmission version has Unable to install due to size issue. The X-shaped reinforcement at the rear has appeared since the NC, and the triangular opening in the middle is designed to be lightweight.

There is an aluminum alloy longitudinal reinforcement with a lightweight design around the transmission shaft, and its two ends are connected to the gearbox and rear differential. This reinforcement called PPF (Power Plant Frame) can be regarded as an independent longitudinal beam that improves the rigidity of the body. It is a very important part for the MX5. It has existed since the first generation NA model and is still used today.

The front and rear subframes are made of high-strength steel and have a perforated light design. The rear subframe structure adopts a triangle with stronger mechanics. Compared with the NC's rectangular rear subframe, the new design can not only improve the rigidity of the rear axle, but also ensure that the impact force is better absorbed by the body, and also reduces the use of materials and reduce weight.

· Suspension system

In terms of suspension, the MX-5 ND uses a front double wishbone independent A combination of suspension and rear multi-link independent suspension. This suspension form is more stable for wheel control and is also one of the most common forms in sports cars.

The structural feature of the double wishbone independent suspension is that the steering knuckle consists of two upper and lower control arms. Connected, compared to MacPherson suspension, the existence of the upper control arm provides better lateral rigidity and higher structural stability. The geometric changes in the suspension work can better adapt to the road surface and maintain the tire contact area, thus having Stable grip performance. In addition, compared with the previous generation car, ND has strengthened the settings of the negative kingpin inclination angle and the negative kingpin built-in amount of the steering knuckle. The effect is that when the front wheels are braking on roads with different friction coefficients, the wheel on the side with high friction will It will deflect slightly to the side with low friction, thereby correcting the vehicle's deviation.

The upper and lower control arms and steering knuckles of the front suspension are made of aluminum Alloy material. The upper control is installed at a lower position of the body, which not only lowers the center of gravity of the body, but also reduces the volume of the steering knuckle and reduces its mass. The lower control arm is equipped with a light-weight design with openings to further implement the lightweight design concept.

The rear multi-link independent suspension is composed of four lateral control arms and one longitudinal control arm , the control arms are all made of tubular steel, which is a very typical Japanese "chopstick" suspension. The bearing seat has a very compact structure and is made of aluminum alloy. MX-5 in NA and NB modelsThe upper rear suspension adopts a double wishbone form, and has switched to a multi-link form starting from NC. However, it can still be seen from the link structure layout that it tends to be A-shaped, which means that its dynamic performance will be close to the characteristics of a double wishbone.

The longer rear lower control arm mainly manages the rear wheel toe angle. The shorter front lower control arm is installed under the bearing seat and is responsible for controlling the rear wheel camber angle. It also works with the longitudinal control arm to guide the wheel's upward jump angle and suppress vehicle roll.

The rear anti-roll bar of the MX-5 ND is very interesting. It is basically the smallest of any car I have ever seen. This is a deliberate move by Mazda, although it is relatively small. Thin anti-roll bars will reduce the vehicle's limit, but it can allow the driver to experience more driving pleasure brought by the vehicle's center of gravity shift. This shows that it is positioned as a Fun Car rather than a Track Car.

The connection between the lower control arm of the front and rear suspension of the MX-5 and the subframe uses eccentric bolts. The advantage of this design is that the inclination and angle can be adjusted through the eccentric bolts. The vertical angle, as well as the wheelbase of the wheel on the same side, but it should be noted that such a setting has relatively high requirements for the machine that performs four-wheel alignment, and the wheelbase on the same side must be calibrated before each positioning adjustment, and then adjust other parameters, otherwise it will be difficult to adjust the positioning data to a reasonable range.

· Driving experience

The "human and horse integration" emphasized by Mazda is a unique driving feeling, and This feeling is very intuitively displayed on the MX-5 ND. First of all, the compact body size and the 50:50 front-to-rear weight distribution allow you to feel that the four wheels of the vehicle are extensions of your limbs while driving.

Secondly, its very low sitting position and almost zero sound insulation will increase the speed of the vehicle visually and audibly. I remember when I drove the MX-5 for the first time, I was driving 80km/h on an elevated highway, but the perceived speed was already over 100km/h. This is similar to the fact that although the speed of go-karts is usually 20-30km/h, we still find it very exciting to drive.

Different from our general concept that the heavier the steering feel, the more controllable it is. The steering feel of the MX-5 ND is very light, so light. There is still a little bit of vacancy in the center steering, but the actual driving is very precise, and it feels like you can accomplish something easily with twice the result.

In addition, it also has its original vibration damping adjustment, which plays an important role in establishing steering feel. Many people, including some professional racers, have complained about the MX-5's roll coming very early and to a very large extent. It rolls when you turn the direction slightly, which is tantamount to an amplified steering response.

When I first drove this car, I also felt that this adjustment was not right., until one time I drove it to Siming Mountain and made continuous turns on the mountain road. The vehicle kept rolling back and forth, but the wheels always firmly grasped the ground. Later, I finally understood Mazda’s good intentions. Let's put it this way, this kind of adjustment of the MX-5 will scare people to death before overturning. The limit of the vehicle is much higher than you think.

Because of the posture of the car body, I have changed a set of coiled shock absorbers. The roll is much smaller than the original one, and the limit is Also higher. But from the beginning to the end, I think the driving pleasure is far less than the original factory vibration damping. This is also the first time that I feel that "everything is stable" is not as good as "the horse is still riding high".

Editor's comment: When compiling the information to write this article, the word I used most was "lightweight". These three words have a high appearance rate. It even made me suspect that my vocabulary was not rich enough, but this is indeed the result of the design goal of "returning to NA" proposed by the MX-5 ND at the beginning of the project. "Returning to NA" is not only about reducing the weight and size of the car body, but more importantly, it is about returning ND to the origin of "human and horse integration". It is a car that will put a smile on your face when you drive it. Even though I have owned this car for more than 3 years, I still feel like this every time I drive it. Just like the sentence "Let's go play Zoom-Zoom", because I believe that when every child says this sentence, there will be a smile on his face.

Note: Some of the pictures in this article come from the Internet and official sources.