[Obioban]

Originally Posted by GR///M3

i like this thread ... thanks for starting it Obioban.

for an 18" wheel, it looks like 255 and 285 would be the best size choice since it's closest to OEM ... a little cautious about the rear circumference being .6 inch smaller than OEM, but that's really not a lot. my question about this size set is:

would there be rubbing issues with an OEM suspension ? would they look really awkward when they are mounted on an 8.5" (255) and 10" (285) ? current OEM setup with 225 on 8" and 255 on 9" the fronts look to be a bit stretched (slanted sidewall), while the rears have a nearly vertical side wall

255s fit on 8.5s well enough.

Rubbing will be determined by offsets.

[Fuerza]

Originally Posted by normcaldwell

Member M3R1 had 255/285 mounted on 8.5 and 9.5 wheels. Maybe the pics in these threads will at least give you some idea about how it looks and handles.
http://www.m3forum.net/m3forum/showthread.php?t=206823
http://www.m3forum.net/m3forum/showthread.php?t=216851

His car was slightly lowered with the Dinan suspension, and he sold the tires not long after he posted the above thread.
I think he was getting a bit of rubbing, but I'm not sure where; probably on the fender, vs inside.

Those look incredible! Was he rubbing on the fronts or rears? or both? A lot of aftermarket wheels come in 10.5 rears and that IMO seems too wide! With these being 9.5 rears I would think that wouldn't be much of an issue, but it seems like 285's are just to wide for our cars.

[normcaldwell]

Originally Posted by Adgar

Those look incredible! Was he rubbing on the fronts or rears? or both? A lot of aftermarket wheels come in 10.5 rears and that IMO seems too wide! With these being 9.5 rears I would think that wouldn't be much of an issue, but it seems like 285's are just to wide for our cars.

He sold the tires a month after installing them.
http://www.m3forum.net/m3forum/showthread.php?t=217797
In the thread, post #29, he indicates a bit of rubbing, and I interpret it to mean the rears.
His wheels were the very same ones I have; Volk TE37 18x8.5 ET35, 18x9.5 ET22.

It appears to me that a very mild drop, with a bit more negative camber (and all that goes along with a proper 4 wheel alignment), and the 255/285 combo would not rub.

By comparison, I'm running stock sizes 225/255 on the same wheels.
I like how the car feels on the street with this setup.
One of the main reasons I have 18" Volks is weight (as in not much weight), along with strength, easy to wipe clean, and I like how they look.

[mosportM3]

Very Nice thread!
Very informative and puts people at ease when trying to play with tire sizes and rims and what to know.

[Mr. Shadow]

Originally Posted by Adgar

Those look incredible! Was he rubbing on the fronts or rears? or both? A lot of aftermarket wheels come in 10.5 rears and that IMO seems too wide! With these being 9.5 rears I would think that wouldn't be much of an issue, but it seems like 285's are just to wide for our cars.

He rubbed because the offset on the rears were ET22 which is very aggressive for a 9.5 wheel. You want no more than ET25. I ordered my volks with a 9.5 ET28 so I can run up to a 285 with no rubbing.

[DuncanS]

Originally Posted by drmillerm3

+1. If what you say about dsc in regards to smaller rear tire diameter is true, why is the optional oem 19" size 245/35F 275/30R, vs 245/35 285/30. considering the 275/30 is near an inch smaller the the 245/35?

So 245/285 is more optimal than 245/275, correct. I need to replace my rears. I have 275/30 right now and they do look a bit shorter than the fronts.

[theBeachBoy]

255/35/19, circumference: 81.8"
and
285/30/19, circumference: 80.8"

in theory, 295/30/19 gets circumference of 81.6, closer to 81.8 and only .2 off like the stock setup.
but I guess 295 is too wide?

Also, I don't know about car tires, but for trucks, the real height is way different from one brand to another (diameter), I'm quite sure it's also different on car tires?

[Obioban]

Width tends to vary from one brand to the next. Height tends to be more consistent.

To you two considering 285 and 295 rears (especially 295 guy)-- you better be really careful with your offsets. Otherwise you're going into run into space issues, fast!

[DuncanS]

I'm running Volk 9.5f and 10.5 rear. Cant remember the offsets, but they are the usual for the 9.5/10.5 setup. 275 looks a bit stretched.

[TRACK-CZAR]

I created the attached spreadsheet with calculations of tire sizes in 18" and 19" diameters.