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[Chris N]

I bought a used set of Apex Arc-8 18x8.5 square with 255/35 Hankook Ventus R-S4 tires. My 128i has M3 front control arms, BMWP springs with Bilsteins, but no camber plates yet. I have about .5 degrees negative camber currently. I didn't really expect them to fit without rubbing based on multiple threads and the Apex fitment guide, however, I decided to test fit them anyway. Test driving resulted in no rubbing anywhere with steering wheel lock in both directions. Can anyone maybe tell me why??

[BimmerAg]

You got lucky? Everyone's car is a bit different in regards to what will and won't rub. Did you go over any bumps at speed or turn sharply under braking? I have tires that almost never rub under normal driving but will in those specific circumstances.

[TboneS54]

Tire brand matters too, but not sure about R-S4s. The 255/xx/xx number system is only general like 5w30 oil. The real width of the tire might be a bit different just like the viscosity at 100degree of two 5w30 oils can be a bit different.

What's helping you for sure is that 8.5" isn't that wide and et45 is the right offset for this car. If the car feels a little sluggish or heavy up front, you could go down to 245 even 235 for a little faster turn in and really avoid any possible rubbing.

[Gangplank]

If you have the M3 control arms they add a bit of negative camber from stock. So you may be at -0.8 give or take. If you pull the alignment pins that will take it up over -1.0 to -1.4.

And good to know because I'm considering a set of 18x8.5 et45 for my 135.

[Chris N]

I did go lock to lock, but I didn't have a chance to safely push the car too much. Maybe that's it.

And, yes, the alignment pins have been removed.

I'm planning to add the camber plates before the next track day and this wheelset will be dedicated for the track, at least for awhile. I guess I will just run them.

[TboneS54]

Even without the plates, with m3 arms and pulled pins, you've got to be over -1 degree camber. I'm hoping for -2 or close to that with dinan plates, M3 arms & pulled pins (which you have to anyway for dinan plates).

[Gangplank]

Just for reference with the M3 arms and alignment pins out I’m at -1.4 up front.

[Rmtt]

Originally Posted by Chris N

I bought a used set of Apex Arc-8 18x8.5 square with 255/35 Hankook Ventus R-S4 tires. My 128i has M3 front control arms, BMWP springs with Bilsteins, but no camber plates yet. I have about .5 degrees negative camber currently. I didn't really expect them to fit without rubbing based on multiple threads and the Apex fitment guide, however, I decided to test fit them anyway. Test driving resulted in no rubbing anywhere with steering wheel lock in both directions. Can anyone maybe tell me why??

Have you hit any hard dips yet to see if anything rubs when the dampers compress? Typically that is where most see an issue.

I'm running the exact wheel (18X8.5 ET45) but with a 245/35/18 Continental Extreme Contact Sport Square setup on a 128i M Sport. I have no suspension mods, just what came with the car.

Apex told me I may need a 5MM spacer up front, but so far I have not had any issues at all. They said a 235/40/18 would work with nothing needed, but I went a little bigger as they looked better on the car.

But I have tortured this little car with the wheel and tires above with no problems rubbing yet!

[Eyeman]

That's cool that a few of you don't rub in the front with those tires and wheels. Your wheel/tire must be a mm from the strut. I'd still be cautious at first or with a tire change etc whenever you are turning and your front suspension is compressed or if you have extra weight in the car.

[TboneS54]

Good to know, planning on getting ARC8s in eitger 8.5" square or 8/9" stagger and debating 235 or 245 tires, not to mention which offsets. Probably will go with the recommended, then add 3 or 5mm spacers just to get a bit more extension, after I've gotten as much neg camber as I can F & R.

[ApexWheels]

Originally Posted by Chris N

I bought a used set of Apex Arc-8 18x8.5 square with 255/35 Hankook Ventus R-S4 tires. My 128i has M3 front control arms, BMWP springs with Bilsteins, but no camber plates yet. I have about .5 degrees negative camber currently. I didn't really expect them to fit without rubbing based on multiple threads and the Apex fitment guide, however, I decided to test fit them anyway. Test driving resulted in no rubbing anywhere with steering wheel lock in both directions. Can anyone maybe tell me why??

Hi Chris,

As a few others have mentioned, every car is slightly different and even identical fitments can produce varied results on similarly set up cars. Typically with an 18x8.5" ET45 squared setup on the 1-Series, a 5mm spacer is going to be required with wider and more aggressive tires. From our experience, a 245/35 or 255/35 will generally need to use a 5mm front spacer with stock suspension, or potentially a larger one if running aftermarket coilovers with reduced inner-clearance, as well as front negative camber dialed in.

Are you currently running any spacers up front? I would be interested to see how much inner clearance you have in the front between the tire and suspension components if you are running this setup without a spacer. Would you be able to share any pictures by chance?

-Geirsen

[thez99]

Just curious, those running the M3 front arms, are you all running the full upper and lower arm M3 set? If so couple questions. 1. Did you do the install yourself, how easy was it? 2. Does installing them instantly correct and add the negative camber or is another alignment required after to add it in?

I'm considering the M3 arm set up front not only for the less understeer and more solid road feel benefit but also the slight neg camber boost

[lowside67]

Installing the arms will give you the camber right away (they aren't adjustable so they just bolt on) but you'll need an alignment as your toe will be off quite significantly.

-Mark

[TboneS54]

Increasing neg camber should cause front wheels to toe out on a MacPh setup.

[thez99]

Originally Posted by TboneS54

Increasing neg camber should cause front wheels to toe out on a MacPh setup.

Sorry for my dumbassness, can you explain this a tad more

[lowside67]

The toe arms are on the back side of the knuckle.

Adding longer control arms moves the knuckle (wheel) outwards.

If you don't lengthen the toe arms and keep them unchanged, then you will effectively pivot the wheels outwards at the front (toe out).

The addition of the control arms is a significant change in geometry and you have to get an alignment, it would be undrivably toed out if you changed nothing.

-Mark

[TboneS54]

Originally Posted by thez99

Sorry for my dumbassness, can you explain this a tad more

At least on typical BMW setups with macpherson struts up front and arms in the rear, as the wheel moves up and down through its arc, camber & toe change - they're dynamic.

Up front, as the wheel compresses, you get more negative camber (wheel tucks in), but the wheel also turns outward (toe out) while it's squatting.

In the rear, it's opposite. The wheels turn in as it squats.

When you change ride height, camber changes. When camber changes, toe changes.

So you get your ride height set, (castor done first, if you have plates) then your camber, then set toe last.