im not sure if this is the right board to ask this but i am looking for aftermarket set of wheels i know they have to be 5 x 4 3/4 but what backspacing do i need. or i should say what size offset are the original iroc wheels? i want them to sit about the same as my stock irocs.

 

also if i get 17's what is a good tire size i want the same size front and back but what size 17' tire would about be the same height as 245/50/16's on iroc wheels?

 

When I went with new chrome ralleys, I was replacing the factory 15 inch wheels with 15's but I think that the offset would not change just because you'd be running a larger diameter rim, the 15 X 7 fronts I ordered with a stock 4.5 inch backspacing, and on the rear I used a set of 15 X 8's and had them made with a 5.5 inch back space. They looked perfect. I drove them for five miles (from the old garage to the garage at the new house) and sold them to get my factory WS6 16's