Look at the hub parameters: ET, PCD, J values ​​are all?

Judging whether a new hub is suitable for replacing the original hub is mainly determined by four parameters: hub width, hub offset, center hole size, and hole pitch. So, what are the specific meanings and functions of these four parameters?

First, the hub width (J value): the tire width is determined by it

The hub width (J value) is the distance between the flanges on both sides of the hub. The "7.0" in the new hub refers to 7 inches, and the "J" represents the shape and height of the hub flange (and the heights of C, JJ, JK, K, etc., C is the lowest and K is the highest). The width of the hub determines the width of the tire that can be installed. According to the data in the table below, the sagitar champion's ten wheels and the 215mm wide tires are the best pair.

Second, the hub offset (ET): whether the friction body is determined by it

The unit of the hub offset (ET) is mm, which is the distance from the hub centerline to the mounting surface. ET comes from the German EinpressTiefe, literal translation is "pressing depth". The smaller the offset, the more the wheel hub will be out of the car after installation. The new wheel hub offset is 54mm, while the small high original wheel hub has a 51mm offset, so the new wheel hub will be retracted 3mm later. The offset determines whether the hub is rubbed against the vehicle components. If the offset of the new hub is larger than the original hub, or if the width is too large, frictional vehicle suspension may occur. In this case, we only need to add a gasket to reduce the hub offset to solve the problem.

After reading the string of "7.0J¡Á17H2 ET54", don't rush to put the wheel on the car. There are still some places to pay special attention to.

Third, the hub center hole: whether it is installed securely depends on it

This is a good understanding, that is, the round hole in the center of the hub. The size of the center hole of the Golf 6 hub is 57.1mm. We should also refer to this value when choosing a new hub: a hub larger than this value must be attached to the axle of the automobile bearing shaft, otherwise there will be a trembling phenomenon. So what about the hub that is smaller than this value? No need to ask, naturally it is not set.

Fourth, the hub hole spacing (PCD): whether it is up to it to decide

This parameter takes some time to understand. Taking Golf 6 as an example, its pitch is 5¡Á112¡ª5 means that the hub is fixed by 5 screws, and 112 means that the center points of the five screws are connected into a circle, and the diameter of the circle is 112 mm. If the hole distance does not match the original car data, the method of installing the gasket and the collar can not be remedy. If you encounter this situation, you can only blame yourself for not considering it.

Fortunately, this set of Polish Sagitar champions ten wheel hubs also belong to the ranks of Volkswagen's original accessories. It is definitely suitable for being installed in Xiaogao, which saves a lot of time for converting parameters. If you want to buy non-original wheels, you can't be lazy when you treat the parameters mentioned above, otherwise you will only embarrass yourself.

The wheel hub is one of the most common vehicle modification components. The modified wheel hub is either sleek or low-key, or luxurious or rustic, all of which highlights the personality of the owner. Wheel modification is generally most suitable according to the size of the original wheel hub. If you want to pursue visual effects, blindly pursue large-size wheels and large flat-ratio tires, but it will affect driving safety.

Alloy wheels reduce fuel consumption

It is understood that the current wheel hubs on the market can be divided into two categories: steel hubs and alloy wheels. The master said that the steel wheel hub has a simple manufacturing process, relatively low cost, and strong resistance to metal fatigue, and it appears in the original low-profile models. However, the disadvantages of the steel wheel hub are relatively prominent, that is, the weight is large, the inertia resistance is large, the heat dissipation is also poor, and it is easy to rust.

Relatively speaking, the weight of the alloy material hub is relatively light, the inertia resistance is small, the production precision is high, and the deformation at high speed is small. The small inertia resistance is beneficial to improve the straight running performance of the car and reduce the rolling resistance of the tire, thereby reducing fuel consumption. In addition, the thermal conductivity of the alloy material is about three times that of steel, and the heat dissipation is good, which plays a certain protective role for the braking system of the vehicle. Alloy wheels are mostly made of aluminum alloy. Compared with steel wheels, the price of alloy wheels is more expensive. It is the standard for the original high-end models.

Wheel size parameter

"The size of the wheel hub is large, and the flatness of the tire is higher, the visual impact is stronger, and because the tread is widened, the grounding area is increased, the driving is more stable, but the fuel consumption is also increased." Huang Shifu pointed out that the modified wheel must first Understand the values ​​on the hub, including size, width, ET value, PCD and hole position. The size of the hub is the diameter of the hub. The 15-inch wheel and the 16-inch inch in the 16-inch hub refer to the diameter of the hub. The width of the hub, commonly known as the J value, directly affects the choice of the tire. For the same size of the tire, the J value is different, and the selected tire flatness ratio and width are different.

The ET value is the difference between the intermediate screw seat of the hub and the center point of the entire rim. Generally speaking, whether the wheel is retracted inward or outward after the wheel modification. ¡°Under the premise of not modifying the brake system, the ET value of the modified wheel hub should be the same as the original ET value.¡± Huang Shifu pointed out that the ET value is related to the steering characteristics of the vehicle and the wheel positioning angle. The gap is too large. The distance value may cause the tire to wear abnormally, the bearing is prone to wear, or even the installation is not possible at all.

PCD and hole position are one of the most important parameters of the hub, where PCD is the diameter between the fixing bolts in the center of the hub. In general, the large porous position of the hub is five bolts and four bolts, and the distance between the bolts is different. Taking 5¡Á114 as an example, the PCD representing this hub is 114 mm and the hole is five bolts. For safety and stability considerations, it is best to choose the same PCD as the original car for upgrades.

The most suitable one or two

Then, the bigger the wheel modification, the better? Under normal circumstances, it is most suitable to increase the size of the original wheel hub by one or two. In order to pursue a stronger visual impact, some car owners are more fashionable and beautiful, and pursue large-size wheels and large flat-ratio tires. This will reduce comfort, increase fuel consumption, and even affect driving safety.

In order to improve the performance of the car, blindly increase the hub, so the stability is improved, but the flatter the tire, the thinner the thickness, the worse the shock absorption performance, the greater the sacrifice in comfort, and the more vulnerable. There is also the hole distance, screw eye distance, eccentricity, etc. must be suitable for the original model, rather than picking your favorite shape as you like.