What is Wheel Offset?
Wheel offset refers to the position of the center of your rim compared to where it mounts to the hub. There are three types of offset: positive, zero (or neutral), and negative.
Positive offset is the most common type. In this configuration the “face” of your rim where it bolts to the hub is in front of the centerline of your rim. That means more of the width is behind the lug nuts.
Neutral, or zero, means the centerline is exactly in line with the mounting surface. That means your lugs are directly inline with the middle of your rim.
Negative means your wheel bolts to the hinge deep into the wheel’s width, and more of the tire is outside the lug nuts. You might hear these rims referred to as “deep dish”.
Another way to think of it is this: If the mounting face is inline with the fenders, that’s positive. If it’s in the middle of your wheel, that’s zero offset, and if it’s way back in the rim and the rim protrudes out past the mounting face, that’s negative.
What is Backspacing?
Backspacing is the distance between the back of the mounting face of the wheel, and the back edge of the rim. The “back” refers to the side facing in toward the middle of your car or truck. The “front” is the edge facing the street.
For example, if your rim is 8-inches wide and the distance from the back of the rim to the back of the mounting face where the wheel lugs go is 6 inches, you have a positive offset.
Why do People Choose Different Offsets?
There are lots of reasons the engineers who designed your car, truck, or SUV gave it the offset they did. Your wheels need to clear suspension and brake components, fit inside your wheel wells even when turned, and provide the right balance of stability for handling.
The best rims for your car usually have the same backspacing as factory.
There are a handful of key reasons people might choose different offsets: Style, handling, or because they’ve upgraded suspension or brakes.
Pros and Cons
You can also use a negative offset to increase the track and push your tires out further to the edges of your car without changing suspension.
Done right, this can improve the amount of stability and grip you have when cornering. It can also give you more clearance for bigger brakes or beefier suspension. Drivers also like this configuration for the deep-dish style.
The downside is that this can put more pressure on your suspension components, and cause breakage. It might also cause your tires to rub on your fenders.
Pros and Cons of Zero Offset
When your mounting point is directly in the center of your wheel, the various forces of cornering, accelerating, and braking are transferred more directly to your car’s suspension. This improves reliability and gives you more feel for what your tires are doing.
Pros and Cons of Positive Offset
Style is a big factor in choosing more positive offset. You might increase your positive offset if you want to bring your contact patch more inboard. In some cases, this improves turn-in and makes your car more agile.
Too much can cause the tires to rub on suspension components. It can also make your car less stable and cause tire failure.
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