rims - offset for 18x8.5???

whats going on everyone,

i am thinking about putting on some 18x8.5's on my e36 m3. the particular wheels i want to get come with a few offset choices of 15, 30, or 40mm. i don't know much about rims and tire sizes, and which match together well, so i wanted to ask if anyone knows which combo would be better...

- 8.5's with 245/40 all around
- 8.5's with 235/40 all around
- 8.5's with 235/40 front, 245/40 rear
- or maybe drop the front down to 7.5 & 8.5 rears (w/ 225 in the front?)

1. will any of these combos rub either when turning the wheel all the way, and/or with a drop?
2. is fender rolling needed?
3. will i need spacers?

any and all recommendations or tips are appreciated. or if anyone has a better setup for 18's, that would be great.

thanks alot

tk

Use 245/35R18 and +40 offset. You should not need rolling or spacers but it will be close. Worse case you will need to slightly roll the rear and 3-5mm spacer in front.