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Posted: **Fri Apr 12, 2024 3:49 pm**

Afternoon all, so the plan to run a Square set up on the Mrs 23i is taking shape, two front 326’s inbound next week and hopefully two more I can collect locally over the weekend.

I’m contemplating a 235/35/19 Square set up to keep costs down as the Mrs is budget conscious, and this size hits a bit of a sweet spot in terms of size vs price.

On the basis that the car currently runs 225/45/17 tires on the style 290 17 x 8j ET 29’s as a square set up, a 19x8j ET29 set up on 235/35/19’s feels like it should work nicely, any thoughts?…. Am I missing anything?

Posted: **Fri Apr 12, 2024 4:06 pm**

Non-expert observation—it might / probably will get a bit understeery? My previous cars (MR2 and a corvette) have always had non square setups and don’t respond well to square ones! Curious to hear forum wisdom.

Posted: **Fri Apr 12, 2024 4:12 pm**

MarshMA10 wrote: ↑Fri Apr 12, 2024 4:06 pm Non-expert observation—it might / probably will get a bit understeery? My previous cars (MR2 and a corvette) have always had non square setups and don’t respond well to square ones! Curious to hear forum wisdom.

All E89, E86 and E85 factory 17’s run a square tire set up

Posted: **Fri Apr 12, 2024 4:50 pm**

True-Blue wrote: ↑Fri Apr 12, 2024 3:49 pm Afternoon all, so the plan to run a Square set up on the Mrs 23i is taking shape, two front 326’s inbound next week and hopefully two more I can collect locally over the weekend.

I’m contemplating a 235/35/19 Square set up to keep costs down as the Mrs is budget conscious, and this size hits a bit of a sweet spot in terms of size vs price.

On the basis that the car currently runs 225/45/17 tires on the style 290 17 x 8j ET 29’s as a square set up, a 19x8j ET29 set up on 235/35/19’s feels like it should work nicely, any thoughts?…. Am I missing anything?

Should be fine..

Posted: **Fri Apr 12, 2024 8:18 pm**

From what I have read the staggered set ups make BMWs more understeery than the square ones.

My E90 330i has 8J x 17 wheels and 225/45 tyres all round and it drives fine for a saloon. In fact for a few years I did run it on Style 290s with the summer tyres.

I can't see why what you propose would be an issue.

Posted: **Fri Apr 12, 2024 8:24 pm**

I dont see any issue at all going with the 4 fronts .
Id stagger the tyres though.
215 or 225 40 19 fronts with 245 35 19 rears .

Posted: **Fri Apr 12, 2024 11:08 pm**

Wow well I learned something today. I think my e89 is 255 rear, and 225 front.

Posted: **Fri Apr 12, 2024 11:23 pm**

I'm not sure you did!

I suspect your 35i has staggered wheels so the rear tyres will have to be wider than the fronts because the rims are wider too.

This thread relates to fitting a set of wheels the same width front and rear. So I'm not sure why you'd fit different tyre widths.

Posted: **Sun Apr 21, 2024 10:40 am**

D'oh, only just found this thread

I am about to do the same thing - putting 19" 8J's all round (cracked rear 9J's, etc etc). I am also switching to non- runflats and was planning to keep 225/35 on the front and put 235/35 on the back. Interested to hear if other tyre sizes might work better, and if anyone thinks spacers on the back are worth the bother.

Posted: **Sun Apr 21, 2024 3:09 pm**

I have the 235/35 19R 92y square set up.
The door stickers don’t give the tyre pressures for these.
Can anyone advise of the correct pressures they are Bridgestone Potenza
Thanks for your help

Posted: **Sun Apr 21, 2024 4:41 pm**

Welsh Terrier wrote: ↑Sun Apr 21, 2024 3:09 pm I have the 235/35 19R 92y square set up.
The door stickers don’t give the tyre pressures for these.
Can anyone advise of the correct pressures they are Bridgestone Potenza
Thanks for your help

There never was a 19" square set up..hence why there is no door sticker to that effect..

You must therefore have two fronts on the rears..suggest about 38-40 for those..FWIW

Posted: **Sun Apr 21, 2024 5:27 pm**

Hi
Thanks for taking the time to come back to me.
I guess you are right regarding the set up
Do I run the same pressure on the front as on the rear?
Thanks Again

Posted: **Sun Apr 21, 2024 10:16 pm**

Welsh Terrier wrote: ↑Sun Apr 21, 2024 5:27 pm Hi
Thanks for taking the time to come back to me.
I guess you are right regarding the set up
Do I run the same pressure on the front as on the rear?
Thanks Again

Read my reply..

Posted: **Mon Apr 22, 2024 6:30 am**

Did do so again - Thanks