How much larger can I (safely) go than 16" wheels?

Hello,

I need new tires for my 1996 BMW 740il, and while I'm at it, I would really like to get some nicer wheels to replace the OEM 16" BBS wheels I currently have that came with the car new. (They are a #%$# to clean!)

How much bigger can I go on the wheel size without having a problem with wheel-well rubbing if I get at least 235's (but probably bigger)?

I'm sure I can get away with 17's, but I'd like to also consider 18's if y'all think they would work. If I went with 18's, I'm assuming I would have to get a narrower/lower profile tire. I just want to get something less "doughnutty" looking.

Also, does anyone know the website where you can try on different sized rims and wheel combinations on a virtual model of your own car? I used to spend waaaaay too much time on there but have forgotten which site it was.

Any input would be much-appreciated - thanks!

18X8 and 18X9.5s are the most common upgrade for those cars.

http://www.e38.org/

Here are the BMW M-Parallels that were the stock Sport wheels

http://memimage.cardomain.net/member_images/9/web/177000-177999/177010_99_full.jpg

http://memimage.cardomain.net/member_images/5/web/233000-233999/233886_9_full.jpg

these use 235 and 255 section width tires.

Here are 18x8.5 and 18x10 Rondells:

http://www.e38.org/images/wheels/randyv_rondell_58.jpg

This one uses 19" Hamman wheels

http://www.e38.org/images/wheels/nug_hamann19-2.jpg

Oh, the site you can try on differnt wheels is Tire Rack

http://www.tirerack.com/

These guys sell the M Parallels at good prices in wheel/tire packages for the 7 series:

http://www.thewheelexchange.com/ Check in their "specials" section.

I really like those M-Parallels. I am in Raleigh, so I can get to thewheelexchange.com folks. I called them and they are really nice.

I was wanting the BBS RA's but my husband (who would not care if I put rims from K Mart on the car) nixed the $350+ per wheel price tag.

Those M-Parallels are close and that car in the pic is just like mine. (The white 7.)

For tires, I am going to go with the 235/50 18" Kumho ECSTA ASX I think... It is very close in size to the 235/60 16" and gives me decent handling, great traction and not too crazy treadwear ratings.

Thanks!