question, new to forum and want to make sure i pick up the correct offset for wheels. im sure this has been answered before. i was looking at BBS RX 17x7.5 offset et42. would this fit a stock sport suspension r53? would they fit if coilovers were added? thank you for any advice!

 

Should be fine at stock height. On my 03 R53 I had 17x7 et38 BBS wheels with 215/40-17 tires. Your 7.5 et42 would be similar because a little more offset but a little wider. Usually the rub issue is at the rear outside.
With H&R springs (lowered about 1") I had rubbing at the rear outside on the plastic wheel arch and wheel well liner.
Thus depneding on the tire width you select and how low you go with coilovers, you might have a rubbing issue but it should be easily resolved with a little plastic trimming.

 

I'm running 17x7 et40 with 225x45 and have no problem, but I have camber plates and adjustable rear arms.

 

thank you for the help ..they are wrapped in 205/45 so that should also help!