[dementedgopher]

Hi all,

First post on the forums (I have had a quick search but still getting used to the site, so apologies if this has been posted countless times) and also first time BMW owner! I'm looking at purchasing some Apex Arc 8s for my 2018 RWD 340i and I'm hearing conflicting recommendations for wheel size and tyre size. I would like to stick to 18" alloys as I've heard these are the best compromise for ride comfort and handling characteristics. I will mostly be using the vehicle as a daily, with fast road driving and maybe 1 or 2 track days a year.

Could I get some advice on what would be best for me? If possible I'd love some advice on whether I should stick with the OEM staggered set up or go squared.

Apex have recommended the following;

• Front: 18x8.5 ET38 with 235/40-18 tires // Rear: 18x9” ET42 with 255/40-18 tires

However, I've been told that my best option would actually be to go with the below;

• Front: 18x8.5 ET38 with 235/45-18 tires // Rear: 18x9” ET42 with 265/40-18 tires

Finally, I've been advised this would be the best squared set up;

• Front & Rear: 18x9 ET30 with 255/40-18 tires

Looking forward to hearing your thoughts

[alohasurftoad]

Originally Posted by dementedgopher

I'm looking at purchasing some Apex Arc 8s for my 2018 RWD 340i and I'm hearing conflicting recommendations for wheel size and tyre size. I would like to stick to 18" alloys as I've heard these are the best compromise for ride comfort and handling characteristics. I will mostly be using the vehicle as a daily, with fast road driving and maybe 1 or 2 track days a year. Could I get some advice on what would be best for me? If possible I'd love some advice on whether I should stick with the OEM staggered set up or go squared.

Apex have recommended the following;
• Front: 18x8.5 ET38 with 235/40-18 tires // Rear: 18x9” ET42 with 255/40-18 tires
However, I've been told that my best option would actually be to go with the below;
• Front: 18x8.5 ET38 with 235/45-18 tires // Rear: 18x9” ET42 with 265/40-18 tires
Finally, I've been advised this would be the best squared set up;
• Front & Rear: 18x9 ET30 with 255/40-18 tires

with 8.5ET38 & 9ET42 i'd run 245/40/18 & 255/40/18 for best handling, 235/45/18 & 265/40/18 best ride comfort

if squared 255/40/18 lightly stretched on 9.5ET35. a lightly stretched sidewall provides better support for tracking. 9.5 is also more concave and more aesthetically pleasing, imo and you'll be able to rotate any way with non-directional tires increasing treadlife.

you may also do 255/40/18 on 8.5ET38 if you prefer more rim protection but it will be much less concave. here is Polo08816 running 255/40/18 on 8.5ET38, square. https://f30.bimmerpost.com/forums/sh...83&postcount=4

[danb1979]

Originally Posted by dementedgopher

Hi all,

First post on the forums (I have had a quick search but still getting used to the site, so apologies if this has been posted countless times) and also first time BMW owner! I'm looking at purchasing some Apex Arc 8s for my 2018 RWD 340i and I'm hearing conflicting recommendations for wheel size and tyre size. I would like to stick to 18" alloys as I've heard these are the best compromise for ride comfort and handling characteristics. I will mostly be using the vehicle as a daily, with fast road driving and maybe 1 or 2 track days a year.

Could I get some advice on what would be best for me? If possible I'd love some advice on whether I should stick with the OEM staggered set up or go squared.

Apex have recommended the following;

• Front: 18x8.5 ET38 with 235/40-18 tires // Rear: 18x9” ET42 with 255/40-18 tires

However, I've been told that my best option would actually be to go with the below;

• Front: 18x8.5 ET38 with 235/45-18 tires // Rear: 18x9” ET42 with 265/40-18 tires

Finally, I've been advised this would be the best squared set up;

• Front & Rear: 18x9 ET30 with 255/40-18 tires

Looking forward to hearing your thoughts

Welcome on board; there's a specific UK section where you'll get UK'ers with similar wheels to advise too:

https://f30.bimmerpost.com/forums/fo...412&order=desc

I ran 18x8 OEM BMW 405Ms all round with 235/45/18 Goodyear Assym6s on my F31; the handle superbly, give a great turn in feel and obviously offer better rim protection with the straighter sidewall over the OEM size of 225:



I've just fitted a set of 397s too with the same size tyres; Goodyear all-seasons for my 'winter' set etc



I'm a huge fan of /Apex alloys and the ARC8s would be my choice also; I'd personally run 18x9s all round, offset 30 and go with 245/40/18 tyres

There was a UK owner who sold his Apex ARC8s very recently with the same specs as above, see post 3490 here:

https://f30.bimmerpost.com/forums/sh...0#post30356390

[dementedgopher]

Originally Posted by danb1979

Welcome on board; there's a specific UK section where you'll get UK'ers with similar wheels to advise too:

https://f30.bimmerpost.com/forums/fo...412&order=desc

I ran 18x8 OEM BMW 405Ms all round with 235/45/18 Goodyear Assym6s on my F31; the handle superbly, give a great turn in feel and obviously offer better rim protection with the straighter sidewall over the OEM size of 225:



I've just fitted a set of 397s too with the same size tyres; Goodyear all-seasons for my 'winter' set etc



I'm a huge fan of /Apex alloys and the ARC8s would be my choice also; I'd personally run 18x9s all round, offset 30 and go with 245/40/18 tyres

There was a UK owner who sold his Apex ARC8s very recently with the same specs as above, see post 3490 here:

https://f30.bimmerpost.com/forums/sh...0#post30356390

Glad to see a fellow Prestonian on board too!

Thanks for all this info, love the look of your F31.

The only issue I have with a squared set up is that I like the aesthetics of a staggered set up. I think the only downside of having a staggered set up is that understeer is more prevalent than if it was running squared.

I did think that I was settled on Front: 18x8.5 ET38 with 235/45-18 tires // Rear: 18x9” ET42 with 265/40-18 tires but with your advice I'm back to being conflicted again

[danb1979]

Originally Posted by dementedgopher

Glad to see a fellow Prestonian on board too!

Thanks for all this info, love the look of your F31.

The only issue I have with a squared set up is that I like the aesthetics of a staggered set up. I think the only downside of having a staggered set up is that understeer is more prevalent than if it was running squared.

I did think that I was settled on Front: 18x8.5 ET38 with 235/45-18 tires // Rear: 18x9” ET42 with 265/40-18 tires but with your advice I'm back to being conflicted again

Small world

Yeah I get the want for staggered alloys; I thought that re my Jap import E39 touring and ran staggered OEM E38 Style 37s and then BBS LMs; but went back to a straight set all round and it was a better car for it; ran 15mm spacers all round too, that had the wheels sitting perfectly



I'll be doing the same with my F31; just bought a stud conversion kit and 12mm spacers. Will fit them come early Jan 2024 once the cars out of its extended warranty

Having run staggered set ups before; I much prefer a straight set up now. The handling and turn in feel is so much better IMO

We don't do the miles to worry about tyre rotation; but that's a positive too