Size

The size of the wheel hub is actually the diameter of the wheel hub. We often hear people say things like 15 inch wheels or 16 inch wheels, where 15 and 16 inches refer to the size (diameter) of the wheel hub. Generally, on sedans, with large wheel hub sizes and high tire flatness ratio, it can provide good visual tension effect and increase the stability of vehicle handling. However, this comes with additional issues such as increased fuel consumption.

Width

The width of the wheel hub, also commonly known as the J-value, directly affects the selection of tires. For tires of the same size, different J-values result in different tire flatness ratios and widths.

PCD and hole location

The professional name of PCD is pitch diameter, which refers to the diameter between the fixed bolts in the center of the wheel hub. Generally, the hole positions of the wheel hub are mostly 5 bolts and 4 bolts, but the distance between the bolts varies. Therefore, we often hear names such as 4X103, 5X114.3, and 5X112. Taking 5X114.3 as an example, it represents that the PCD of this wheel hub is 114.3mm, with 5 bolts in the hole positions. When choosing a wheel hub, PCD is one of the most important parameters. For safety and stability reasons, it is best to choose a wheel hub that is consistent with the original car for upgrading and renovation.

Offset

Offset, commonly known as ET value, refers to the distance between the fixed surface of the wheel hub bolt and the geometric centerline (centerline of the wheel hub cross-section). Simply put, it refers to the difference between the fixed seat of the middle screw of the wheel hub and the center point of the entire wheel rim. In simple terms, it refers to whether the wheel hub is retracted inward or protruded outward after modification. For general sedans, the ET value is positive, while for a few vehicles and some Jeeps, it is negative. For example, if a car has an offset value of 40 and is replaced with an ET45 wheel hub, it will visually shrink into the wheel arch more than the original factory wheel hub. Of course, the ET value not only affects visual changes, but also is related to the vehicle's steering characteristics and wheel alignment angle. Excessive deviation values may lead to abnormal tire wear, bearing wear, and even inability to install properly (the brake system and wheel hub cannot rotate normally due to friction). In most cases, the same brand and style of wheels will provide different ET values to choose from, Before modification, comprehensive factors should be considered. The safest scenario is to maintain the ET value of the modified wheel hub the same as the original factory ET value without modifying the brake system.

Central hole

The center hole is the part used for fixed connection with the vehicle, which is the position of the center of the wheel hub and the concentric circle of the wheel hub. The diameter size here affects whether we can ensure that the geometric center of the wheel rim can match the geometric center of the wheel hub when installing the wheel hub (although the wheel hub positioner can convert the hole spacing, this modification carries risks and netizens need to carefully try it out).