I’m trying to run 275/35/18 squared. I have some of the discount tire M parallel replicas, which are 18x9.5 et25. Without a spacer that size rubs the strut so I test fit some 20mm ones off my E39 making the offset now a +5. At full left hand lock the tire rubs the front fender liner.
I just want to hear what some of you are running, I’m thinking it may just be my old fender liners are a little saggy.
I'm running Michelin PS2, 265/40-17 with 9x17-ET-10mm rims with 12mm spacer no rubbing ever.
245/40-18 with ET5, no spacer MK I's , no rubbing.
91 850 (Panzer), 2012 Mini Cooper Countryman (WifeMobile) www.wuffer.ca
Hmm, even though I’m running a wider wheel and tire than both of you the dimensions as far as how far they poke out and what not are about the same. Maybe I should try and put some new wheel liners in and see if that fixes it.
- - - Updated - - -
So your end set up is a 9x17 Et -2
My setup with 9x17" ET is actually 9mm (mistakes in my original reply, explained below)
I think the ET:5mm you are using is the best you can do with 275 section width tire and maintain a reasonable sidewall to strut tube clearance (3-5mm).
Here's the rub, pun intended.
Adding 10mm to the tire section width adds 10mm to the tire tread outside arc path when the tire to strut tube distance is at the limit.
Excuse my difficult to interpret notation ET-10mm should have been ET:10mm
You made me look at my tire/rim Excel offset calculator.
AND
Mistake alert.
The 9x17" rims I'm running are ET:19mm (not ET:10mm) and I used a 10mm spacer so the ET is 9mm.
IMHO, I have the ET as small as it can be to maintain a safe clearance of 3-5mm between the tire sidewall and strut tube.
Also, when I do the analysis for 275 section width tire I get an ET:4mm
It’s not the strut tube that’s an issue it’s at full lock, the outside edge of the tread rubs the front of my fender liners. So rolling down the road if I took a full lock turn it would chew through the liners pretty quickly.
I think you misunderstood my explanation.
While your tire may not be rubbing the strut tube with a ET:5; if it wasn't in the way (I like to keep minimum 5mm clearance) you could run a +15 or 20 ET and the tire wouldn't rub against the fender liner at full steering lock.
As I indicated, my calculations indicate you may be able to run a minimum ET:4 but not much more or the tire will be too close to or rub the strut tube. Also, depending on the tire manufacture and series the actual tire section width could be greater or less than the nominal section width of 275 I used to calculate the ET, so you will want to measure the actual section width and the actual strut tube to tire side wall clearance once the wheel is mounted.
Therefore, as I indicated once you get the tire wide enough you get to an unacceptable option, rub the strut tube or rub the finder liner when the steering is at full lock and you may be there.
With et5, 265/35 might fit without rubbing but that also depends the tyre manufacturer. Keep in mind that 275/35 you are using is also a bit taller (7mm actually) than 265/35. So, with 265/35/18 you should have about 6-8mm more clearence with full lock, in theory, rest is up to tyre brand.
Mk1 is also 9,5x18" et5 and with 245/40 hankook ventus S1evo2 tyre it has about 10mm clearence to fender liner at full lock.
Last edited by mikae31; 11-09-2018 at 10:28 AM.
I guess I’ve just got too big a tire under it.
Would this tool help?
http://www.bmwccae31.com/DOCS/Info/W...Calculator.xls
Its a wheel fitment calculator based on an Excel spread sheet.
-Bob
Bookmarks