Z4-forum.com

First of all apologies. I know this question (or variants of it) crop up all the time. The trouble is I still find it confusing. I've seen the 'will they fit' type pages, etc, but was hoping for some simple ley mans advice from forum members.

I'm looking at a few 18" alloy options. Going OE is simple as I know they will fit, but as soon as you start looking and aftermarket stuff the options are endless.

I have seen a couple of sets that are both 18x8 front, 18x8.5 rears (or poss 9) that are ET34 or 38 front and ET37 or 42 rear. Can anyone tell me simply if a) these will fit ok and b) will I need spacers? If anyone has a similar set-up I would like to see photos.

If you want to avoid asking the forum every time you find a possible wheelset to keep things simple the golden number both front & rear is et40.
Go 8j 8.5j ( F) 8.5j ,9j or 9.5j (R) & stay as near to et40 as possible & you won't fail .
Et 34 front is about the limit with 8j imo & if 8.5j then rubbing is highly likely at certain times .
Rear et30 is about the max you would want depending on rim width