What is offfset??

I currently have the 16" Fuchs. Can someone explain to me what is meant by offset and what I need to do to put after market rims on my car; ie 17". I am assuming that I will need to flare the fenders, but I am not sure about spacers and offset. What do I need to know to upgrade to bigger rims and tires. I do not want to purchase something that I cannot use!!! Thanks!!

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jevose
82 911 SC

The offset is the distance in millimeter between the wheel's middle point and the face of contact where the wheel is attached to the hub. (sorry for not explaining it better, but english is a foreign language for me).

Anyway you should search the archives for a thread called "New Wheels" which covers this aftermarket wheel subject. If you want 17 inch wheels you can get the socalled Cup replicas pretty cheap. They are 7.5x17 front and 9x17 rear. I think the offsets are 23 and 15. These wheels will fit straight onto your SC without spacers (the wheels kind of have spacers built into them already). Recommended tires are 215/45x17 front and 245/40x17 rear. Please notice that the much used 255/40x17 size at the rear will/can rub onto the bodywork. If you go for 245/40 no rubbing will occur. The wheels are MilleMiglia from Italy and built under Porsche license. Avoid the similar looking replica wheels built in Indonesia (don't know the brand name).