Wheel Tech - Wheel Offset
There has always been a problem of figuring out just how large a custom rim and tire can be stuffed into a wheel well of your car, truck or SUV without rubbing on the inner or outer fender.

Negative Offset - Zero Offset - Positive Offset
Offset is the location of the flat mounting surface of a wheel as it relates to the wheel's centerline.
Negative offset means that the mounting surface of the wheel is toward the center of the car. Negative offset is usually found on older vehicles.
Positive Offset means that it is toward the outside of the car, or the wheel is pulled in toward the center. Positive offset wheels are usually found on front wheel drive cars and some small trucks.
Zero Offsets means the measurement to both outer rims are equal.
The offset of a wheel affects many things other than whether the wheel has the appearance of sticking out past the fender. The wrong offset can cause rubbing problems when the suspension is compressed or the wheel is turned. Offset affects the steering radius and possibly leading to other problems.
Offset also affects the suspension's motion ratio, which directly determines the effective spring and damper rates. What this means is you will potentially have wheel bearing failure on a vehicle with improper offset. This especially true with trucks rather than small cars. As you can see it is very important that the proper offset wheels be used.
1969 Chevrolet Nova SS
1955 Chevrolet Bel Air