Here is one of our good customer’s 1998 Lexus GS400 which has 20×9.5 MRR HR3 wheels at all four corners.  The 9.5′s all the way around where chosen instead of  8.5′s up front because the 9.5′s concave in more which looks much better.  This GS400 can easily accomodate 9.5′s all the way around without spacers.  This car actually has 25mm spacers in the back making this rim essentially a +13mm offset.   He has 15mm spacers in the front making the fronts essentially a +23mm offset.  This car is lowered quite a bit on Tein Flex coilovers.  He is also running a good amount of negative camber so the wheels tuck in nicely.  This customer is a perfect example of the type of person that will do whatever it takes to achieve a certain look.  Thats how most of the employees here at Element Wheels feel about our own cars too.  We like to push the limits of vehicle fitment.

Below are pics of the front of the GS400 before and after we installed Ichiba 15mm Hubcentric Bolt-on spacers.

-Chris @ Element

BEFORE:

15mm Ichiba Version 2 Bolt-On Spacer:

AFTER:

The offset of a wheel is the distance from the hub mounting point to the center line of the wheel. This is shown in the image to the left.

A Zero Offset is present when the hub mounting surface is even with the center line of the wheel.

A Positive Offset is when the mounting surface is moved towards the front of the wheel. This is more common on front wheel drive cars.

A Negative Offset is when the hub surface is moved towards the back of the wheel. A negative offset is usually found on wheels that have a very deep lip.

If the offset of the wheel is not correct for the car, the handling can be negatively affected. When the width of the wheel changes, the offset also changes. If the offset were to stay the same while you added width to the wheel, the additional width would be split between the inside and outside. For most cars, this won’t work correctly, and can cause problems.

Some exceptions to what will and won’t work also depend on the overall look you are trying to achieve with the vehicle. Generally, lifted trucks will run a negative offset to create more room in the wheel well for oversized tires, as lowered and bagged trucks will run a high positive offset to make sure the wheel will clear the fenders when tucking inside the well. The same goes for most cars as well, depending on the particular look you are trying to achieve.

Once it’s explained, offset is actually a very simple concept, and the knowledge of your vehicle and the available offsets for your application can make the entire process of selecting wheels much easier.