In question is a set of Supercups.
Front(17 x 9)w/ 51mm offsets (7 in. backspace) Rear(17x11)w/51mm offsets (8 in. backspace)
When looking at wheels, is there a general formula to follow regarding backspacing and offset in relation to the OEM Fuchs? Ex. If you go with a 1" wider rim, you need to increase/decrease the offset or backspace by xxx?
Thanks

 

When I've changed wheel widths I draw all the dimensions I have now. I measure how much clearance there is to the inside and outside of the mounted tire and wheel on the car. Then I take the wheel off and measure the distance from the mounting face to the outside and inside edge of the wheel. With these dimensions drawn on paper, I figure out how big a wheel I can fit (a wheel is 1" wider than the size, ie an 11" wide wheel is 12" wide) and what the offset needs to be.