225/40 front 245/40 rear

[325_driver 422]

Wondering if running staggered setup on a standard rear wheel drive will cause issues.

Ideally I wanted 255/35 on the rear but it wasn't available in the rft.

So anyone know whether having 225/40 front 245/40 rear. Rear wheel drive e91 will have any issues with DSC / ABS due to about 2% diameter difference.

Or only just speedo difference

[polley 916]

I dunno about your e91, maybe its smarter these days. But my e39 asc constantly kicks in with mis matched sizes. Gotta turn it off if want to over take as itll kick in with foot down.

[qube 3570]

i would say it doesnt matter but im more curious why 255/35 is not available as this is the standard size tyre for the style 193 or any other 18" staggered set ups for a lot of sedans.

[325_driver 422]

@qube there are 255/35/18s there for me at the tyre place I get decent pricing through just not in run flat. And I was going all run flat setup on the wagon. Already got a set of eagle f1 225/40/18 before I bought the staggered OEM 193s. So I was there hoping to find something wider for the 8.5" rim.

If that makes sense haha. Cause I ain't justify $500+ a tyre. When I can get a 245/40/18 potenza for $100 at my good mates.

I wonder if 245/40 square will fit? The 255s on the front weren't touching the shock when I test fitted the wheels with hiflys still attached. But maybe Abit more height is getting a tad close.

Edited August 26, 2020 by 325_driver

[qube 3570]

if u wana go square tyre fitment fit 235 40 all round. it will be alright

[M3AN 4016]

Yes, either 235 square or 255/245 on the rear, all will be fine the 2% difference wont matter, the 245 is a common paring to a 225 front (it's a setup I'm actively considering for my 130i). Your speedo is already >2% inaccurate.

I'd advise against a square 235 setup though, you're better off staggered and it will be nicer to drive.

Of course your best choice would be to dump the runflats.

 

Edited August 26, 2020 by M3AN

[325_driver 422]

@M3AN yeah wanna try run flats for a few kms since a friend is trying to move stock cheap.

I think I'm going to leave BBS on front with 225/40/18 and put the 193 on rear with 245/40/18 take her for a spin see if I can trigger and DSC due to the front rear rolling diameter difference. And then get the front 193s fitted with 225/40.

Keep reading up on strange things with DSC but it all seems to be xi model related.

Out of curiosity, how wide will e9x handle 265/35? This site seems to suggest anything you to 275 is a direct fit on rears https://support.apexraceparts.com/hc/en-us/articles/360001593193-E9x-M3-Wheel-Tire-Fitment-Guide

Edited August 26, 2020 by 325_driver

[qube 3570]

how cheap is cheap? what sizes available and what brand/model RFT?

running those sizes wont have any issues with your DSC.

 

there is no point discussing wide tyre fitment without specifying the wheel size/width/offset at the same time.

can you run 265/35 rear? yes. on a 8.5-9.5" rim with approx 22-35 offset.

this is what I was running on our old E91 325i but later switched to 255/35 as I had the tyres.

can you run 275/35 rear? yes. on a 9.5-10" rim preferably. you will need around 35ish offset.

 

btw, your link is for E9x M3 fitment.

this is the correct guide, and refer to the non LCI because it is different to LCI fitment for wheels.

https://support.apexraceparts.com/hc/en-us/articles/360001673834-E9x-3-Series-non-M-Wheel-Tire-Fitment-Guide

 

Some of my old pics for ref

m pars aka style 37 : 18x9.5 et25 rear with 265/35

Bbs RS-GT RS912: 18x9.5 et22 rear with 255/35

Style 225 19x9 et39 rear with 265/30 

 

Edited August 26, 2020 by qube

[325_driver 422]

@qube ^^ that's exactly what I was looking for, I now see why they call you the wheel God on here haha.

The RFT are Bridgestone potenzas, they cheap because they are getting out of that particular market and I wanted to give them a try.

At $100 a tyre I wasnt really aiming for perfect setup, just double checking a staggered fitting wouldn't throw me into things like polley was talking about with e39.

After this I will probably go back to non run flat and 255/35 rear 225/40 or 235 on fronts.

Edited August 26, 2020 by 325_driver

[zero 1162]

@qube the wheel god

 

Lets make than name stick, and then you will have to add it to your sig

[qube 3570]

I not really that knowledgeable compared to the likes of some other more experienced members who are experts in wheel/track geometry etc. But i know how to understand and decode tyre size numbers and calculate wheel width vs offsets with respect to a certain car from trying various wheels etc. its really just information comprehension. 
 

also i know how to properly google search a lot of stuff haha

[325_driver 422]

@qube yeah was just going to rock staggered setup but was doing some digging before I paid the tyre fitters, and the only real info I found obviously was xi models. Nothing conclusive on a rwd e9x and DSC sensitivity to staggered setup.

So thought I'd atleast put the question out there. It's nice to know someone on an e39 had an issue. A mate of mine with e39 is also thinking of staggered so I'll tell him to steer clear of too much variance.

You don't happen to know if BMW specifies tollerances for non xi / xdrive? I've read xi models is listed at not to exceed 1% Rolling diameter.

 

 

[M3AN 4016]

You're not going to have a problem on a RWD with a staggered setup, pretty much every high horsepower RWD depends on a staggered setup.

You only need to be concerned about rolling circumference and you can be miles out before that will bugger with traction control which, in most cases, measures the difference across an axle before it does front to rear.  

[325_driver 422]

On a side note question. Anyone driven 255s on an 8" rim before? I know 8.5" is the ideal minimum rim width for 255s and above but curious if a 255 on 8" will feel "mushy" with say on some hard cornering.

Basically think off putting some 255 (rear) on the BBS rims which are going on the 325ci

[qube 3570]

not recommended nor legal

255/35/18 must be on a 8.5-10" width rim

https://lvvta.org.nz/documents/infosheets/LVVTA_Info_01-2009_V3_Tyre_Size_to_Wheel_Size_Compatibility_Guide.pdf

[325_driver 422]

@qube thought so. Looks like I'm hunting for more rims haha. Maybe 193 will look cool on the e46

[qube 3570]

It sure does. Fits like a glove too

225/40 + 255/35

[325_driver 422]

Fak. Might keep the BBS on the e90 and the 193 on the soon to be steel grey e46. Could be the winning combo.

[325_driver 422]

@qube any guard Rolling required on that above setup e46? For 255 rears. What about 265?

[qube 3570]

no guard rolling required 18x8.5 ET37 offset with 255/35/18.

I did have to roll on a previous e46 but i was running 235/40/18 on 18x8.5 ET22. 

i would stick with 255 35 18 if i was you. also mine is a coupe, not sure if it is much diff to the touring, never had a e46 touring before but I think its the same or similar

[325_driver 422]

@qube it's funny I got the 193 because I didn't want it let go of the BBS if I sold the wagon when I finish the coupe. But now I don't know if I could sell the 193s. 

Suppose I could always find another set of 193s. I always see them when I don't need them. And when I want them they are never there.

 

[qube 3570]

11 hours ago, 325_driver said:

Suppose I could always find another set of 193s. I always see them when I don't need them. And when I want them they are never there.

exactly. Ive been looking for a few weeks now but cant find any... 

[325_driver 422]

@qube you mean these ... https://www.facebook.com/marketplace/item/319865322586075/

 

[qube 3570]

Yea too exp anyway. Can normally get them with tyres for $6-800.

We ended up going for 17” style 194s with tyres for $400. It was for a friends car who had 19s and found the ride too harsh on runflats. 

[325_driver 422]

@qube have some continentals 255/35/18 if you ever want them cheap since I'm running run flats for a bit. Like $200 for pair delivered or something. PM me if you ever need them they just going to be looking at me in my garage for some time. Haha