[dgluyas]

Hi Ian ! It all depends on your current offset. I am running 16x7 and 16x9 Porsche fuchs. The offset is 23 front and 15 rear . I do have a narrowed front beam (2 inches) and a narrowed rear (23mm per side ) with 2 inch wider rear guards. If you are converting from your fuchs you need to find out your offset ,its stamped on the inside of your wheels. Then visit the wheel offset calculator on the net and plug in your boxter dimensions and it will calculate how much your wheel moves in and out for different sized wheels. Have a look in the first post in this section from me to get the website and it should help. Good luck.
David