Offset is the plain of the wheel where it joins the car ie how far laterally/medially it falls.

Most 16" wheels will not fit on your car. They may if you use spacers which will unbalance the suspension and cause premature wear.

Do yourself a favour and stick with wheels that are made for your car. It will thank you for it with longevity. Expensive yes, but then so is the car. Your local tire man wants to make a quick sale and doesnt give a s$#! what happens to your car.

At Discount Tire I saw 17 inch rims selling for $115 each (which is cheap....and they were MAS a company that makes BMW OEM wheels) .

Good luck.
I was just told, contrary to previous recommendations, that I do not need to have a 17" rim for my Snow tires for my 330cic sp.
I was told, from a tire dealer, that I could go with a smaller rim with and "offset". What is an Offset, and will this work with my 330cic?????
I was originally told that the 17" rims were mandatory for the sport package 330cic in order to clear the brakes?
Help!!!