Apex ARC-8 recommended size for E86 M

[ah-]

Hi,

it's time for some new tires and I'm looking to replace my 19" CSL replicas with 18" ARC-8s for a slightly more comfortable ride on UK roads.
But I'm not quite sure what size and ET to pick. Car is slightly lowered in the back and stock up front, street use only.

I've read through https://www.zpost.com/forums/showthread.php?t=473674, https://support.apexraceparts.com/hc/en ... ment-Guide and a couple of posts here, just want to double-check it'll all fit nicely.

Current wheels/tires:
Front 235/35/ZR19 on 2282650, EH2 IS44, RC 337
Back 265/30/ZR19 on 2282660, EH2 IS27, RC 338

Considering this:
Front 235/40-18 on 18x8.5" ET35 or ET38 (any meaningful difference between ET35/38?)
Back 265/35-18 on 18x9.5" ET22

Any thoughts or advice highly appreciated

[Papa_Zee]

Ah,

I've always preferred the 18" 224s and think they suit the car so much. I was inclined, come tyre change time to go for the widest 18 I can get away with on 224's. Are you saying though that you prefer 18's to 19's? As I still always wonder if I am missing more than just the looks of 19's (CSL Reps)?

Papa

[ah-]

I quite like the 19" wheels looks wise, just would like to improve comfort on bumpy roads a bit.
224s are my next favourite style after CSL, but I don't think I'm ready to go there yet

This is how the car looks right now:


18" ARC-8 looks like that:


19" ARC-8s look great as well but I fear then I'm back to a bumpy ride:

[Papa_Zee]

The 19's do look good but I prefer comfort, I wouldnt want to go to 19's CSL and then back to the 224's. i think I will stick with them.
As said on some posts, the 18's suit the MR and 19's suit the MC.

I am going for this look...
Not quite as low, mind.

[Ed Doe]

It's quite aggressive, but imo you really do need to get the concave ones - they look so much better, but does mean you need to be aggressive on the width and offsets.

I currently run apex ec-7 alloys - 8.5j front and 10j rears. I purchased the car on them - the only thing i wish the car had is a more aggressive front width - id have loved to get 9 or 9.5 fronts. 10j looks perfect on the rear imo.

Pic of mine on ec-7s for comparison :

IMG_20190323_144723.jpg (353.02 KiB) Viewed 2195 times

So with arc-8s I'd go for:

Front - 18 x 9.5 et 22 with 245/40/18 tyres
Rear - 18 x 10 et 25 with 285/35/18 tyres.

This is the pic with those exact wheel and tyre sizes fitted. Imo it just looks perfect

8010323146_36bf3b1c06_b.jpg (155.31 KiB) Viewed 2195 times

[MrPT]

I quite like the 19" wheels looks wise, just would like to improve comfort on bumpy roads a bit.

After a bit of experimentation I’m running 265/35/19 and 245/35/19 now. It’s worth considering if you like the look of the CSLs but want a slightly better ride.

[MrPT]

Here’s a pic. You definitely sacrifice a bit, looks-wise, but the pay off is worth it. They are the same sizes as an M2 and firmly within the recommended widths for 8.5J and 9.5J. They’ll also make the handling a little more neutral and are closer to the stock Z4M diameters than the CSL sizes you have at the moment.

47064AD6-5CC4-43C9-B36E-16A77E81AE66.jpeg (414.59 KiB) Viewed 2141 times

The car is currently lowered 5mm at the rear and 10mm at the front vs stock, and the front camber is -1.3 ish.

This is the pic with those exact wheel and tyre sizes fitted. Imo it just looks perfect

8010323146_36bf3b1c06_b.jpg

I've had that pic saved for years now. Agree it's dead on.

So many guys in the US are running with rolled arches and crazy camber though. Square setups are like the holy grail of handling solutions, for some reason (maybe because they like a lot of metal over the front axle and their roads don't cause tramlining?!).

[Ed Doe]

This is the pic with those exact wheel and tyre sizes fitted. Imo it just looks perfect

8010323146_36bf3b1c06_b.jpg

I've had that pic saved for years now. Agree it's dead on.

So many guys in the US are running with rolled arches and crazy camber though. Square setups are like the holy grail of handling solutions, for some reason (maybe because they like a lot of metal over the front axle and their roads don't cause tramlining?!).

it was saved on my computer for years when I had my silver grey Si - I spent a long time on willtheyfit.com trying to work out what I could get away with in terms of dish etc. Sadly it was never going to work with the si hubs!

I think a square setup is optimal for track use mainly because you don't tend to have to run as much camber to get sharp turn in and good front end stability. At the limits, the front will tend to push more as it has inherently less tyre contact patch and thus less mechanical grip. The difficulty is as you say on this platform to run big width on the front does also require a fair bit of camber so it then becomes very 'tram-liney'!
I think there are far fewer badly maintained roads with big crowns in the middle in thr states - most heavy trucks stay on the freeways so the fun roads are less beaten up (that's my logic anyway?!). Either way I still have a secret hankering for that setup, in gold on my M I doubt it'll happen though - trackdays first haha!

[Nuts]

Just to resurrect this thread… do we think these are 18" ARC-8 because to me they are perfect!!

IMG_1007.jpeg (144.45 KiB) Viewed 363 times

[B21]

Just to resurrect this thread… do we think these are 18" ARC-8 because to me they are perfect!!

IMG_1007.jpeg

Yup look like Arc-8s..lovely..

[Trav]

20230414_140427.jpg (228.45 KiB) Viewed 345 times

20230414_140508.jpg (236.35 KiB) Viewed 345 times

Mine is running the following

Front: 18 x 8.5 ET38. With 235/40/18
- Rear: 18 x 9.5 ET22. With 255/40/18

Maybe not as extreme a look as some want. But no comfort lost for sure.

[Nuts]

I’m about to buy an e86 3.0si so wondering whether 9 fronts and 10 rears are the best bet.

[Ed Doe]

I’m about to buy an e86 3.0si so wondering whether 9 fronts and 10 rears are the best bet.

That's a very aggressive width for a non-M, you might struggle to get that in the arch..! I'm sure I saw someone with a 10j rear on an si and the wheel was basically outside the arch lip...

[1536Z4]

I’m about to buy an e86 3.0si so wondering whether 9 fronts and 10 rears are the best bet.

I looked into this and finally went for 18x8.5 ET 38 and 9.5 ET 35 . I wanted to go bigger at the front to get the concave look rather than flat but from what I read they wont fit without issues .

[Nuts]

I’m about to buy an e86 3.0si so wondering whether 9 fronts and 10 rears are the best bet.

I looked into this and finally went for 18x8.5 ET 38 and 9.5 ET 35 . I wanted to go bigger at the front to get the concave look rather than flat but from what I read they wont fit without issues .

Any pics please?