18" winter wheel options/pricing - let's list them here

[Buzz_Lightyear]

BBS SR ??? will it work on M3/4???

[6MMMT]

Originally Posted by Buzz_Lightyear

BBS SR ??? will it work on M3/4???

Tirerack lists it under their new M3 winter wheel package, so it better work. 18x8, $265 each.

[BMWFanatic2008]

What are your thoughts on BBS SR vs Rial P10 wheels?

[CanAutM3]

Originally Posted by mkoesel

Actually, that's not correct.

Running the ET27 wheel in the rear with the recommended 255mm tire will widen the track 3mm vs. running the ET40 wheel with the recommended (stock) 275mm tire. Similarly the E29 wheel, 255mm tire combo widens the track 1mm vs. the ET40 wheel, 275mm tire combo.

Math:

(40 - 27) - ((275 - 255) / 2) = 3
(40 - 29) - ((275 - 255) / 2) = 1

I guess this now begs the question, why run a 9" 640M square setup when you could run an 8.5" 640M square setup instead? It's another option to consider anyway.

I am not sure I follow here...

I have always understood that track width is dependent on wheel offset (ET) only and has little to do with wheel or tire widths. Track width is the distance between the centerlines of the left and right wheels/tires on a given axle, therefore only the offset impacts the position of the wheel centerlines relative to the hubs (with zero camber).

So if you change the wheel offset, you change the track width accordignly. Going from ET40 to ET27 would increase rear track by 26mm regardless of tire or wheel width.

Now, when camber is added it becomes a bit more complex and that is where wheel/tire dimensions are needed, but the effect of camber is almost negligible for similar tire diameters, so the basis still holds.

Am I missing something here ?

[6MMMT]

Originally Posted by BMWFanatic2008

What are your thoughts on BBS SR vs Rial P10 wheels?

Think this was directed at me. I'm no expert on aftermarket wheels or their performance characteristics, so went with BBS entirely on visuals with my black M3. I have the silver 19s stock now, so wanted to mix it up with the matte anthracite for the winter set. And based on my dealer quoting me $2,300 for just the 640M wheel set w/o tires, the $265 per wheel looked like a bargain.

[S801945]

For the BBS-SR - you worried about the extra weight? It's only a few lbs more than the OEM.

[My2ndBMW]

As far as I’m concern, I don’t really care if aftermarket wheel weight more than OEM wheel, as long as the wheel fits without any issue.

I may be alone on this but unless I see a picture of BBS SR or Rial P10 installed on F80/F82, I don’t believe what anyone says about guarantee to work statement.

[MaX PL]

i know this is a winter wheel thread, but i can't believe some of you are considering $200 wheels for a $70k car.

[volkl23]

Originally Posted by MaX PL

i know this is a winter wheel thread, but i can't believe some of you are considering $200 wheels for a $70k car.

I'm definitely in that camp. I'm purely getting a winter setup just to get by winter for the 3-4 months that we have annually. I'm more about function over form in winter. As long as it gets the job done, and if I could do it for cheaper, than why not. Rather spend the extra money I save from getting $200 wheels vs $300-$500 on cosmetic/performance mods.

[S801945]

Agreed... but it's a winter wheel; one could say, why spend a ton of coin on wheels that are going to get exposed to all the stuff that comes from winter.

[Buzz_Lightyear]

BBS told me today by phone , BBS SR impossible to fit the M3 / 4

does anyone have pictures from the built-in state

sorry is google translate

[6MMMT]

Originally Posted by Buzz_Lightyear

BBS told me today by phone , BBS SR impossible to fit the M3 / 4

does anyone have pictures from the built-in state

sorry is google translate

Did they say why it won't fit, what dimensions? How confident are you in this? I've spoken to Tirerack and they said they have tested the fitment themselves, as well as sold it already to other owners. I'm inclined to believe Tirerack but this is my first purchase from them, so we'll see

[My2ndBMW]

Originally Posted by 6MMMT

Did they say why it won't fit, what dimensions? How confident are you in this? I've spoken to Tirerack and they said they have tested the fitment themselves, as well as sold it already to other owners. I'm inclined to believe Tirerack but this is my first purchase from them, so we'll see

I wonder if BBS though Buzz_Lightyear had CCB, in which case we all know that it won’t fit ANY 18” wheel.

In any case, since you have already bought the BBS SR package from Tire Rack, when do you expect to receive the Winter Wheel Package from them? Or did you chickened out and cancelled the order?

[6MMMT]

Originally Posted by My2ndBMW

I wonder if BBS though Buzz_Lightyear had CCB, in which case we all know that it won’t fit ANY 18” wheel.

In any case, since you have already bought the BBS SR package from Tire Rack, when do you expect to receive the Winter Wheel Package from them? Or did you chickened out and cancelled the order?

Haven't cancelled, wheels are in transit. Guess I will see it through and test them out. Will post back with learnings...

[My2ndBMW]

Originally Posted by 6MMMT

Haven't cancelled, wheels are in transit. Guess I will see it through and test them out. Will post back with learnings...

Thanks 6MMMT

Make sure to post a LOT of pictures once you mount them onto M3.

Some of us(mostly me) isn’t convinced that BBS SR will clear the brake without a spacer.

[JoeFromPA]

Originally Posted by MaX PL

i know this is a winter wheel thread, but i can't believe some of you are considering $200 wheels for a $70k car.

Why, do you think wheels are inherently better for winter duty if they are $500/wheel?

Did you know that BMW's wheels they themselves are offering for winter usage in 18" size are ~$300/wheel - is that still cheap?

I think you are confusing the cost of a lightweight high quality forged wheel with the cost of a well made cast wheel.

[CanAutM3]

Originally Posted by gsrbri

Got it. I was thinking less in terms of fitment and more in terms of performance. Maintaining the track width in front and rear is critical for handling...the ET27 wheel in the rear will result in a 10MM reduction, per side, in overall track width. So, the contact patches will be just slightly inboard of where the ET40 offset wheel will be in the rear.

Plus, to your point, factory matched wheel/tire packages have BMW behind it, both from safety/engineering/warranty side, so it isn't a bad level of security to get for a few extra $$.

What am I missing?

You are correct, track width is an important element to consider to maintain the suspension geometry. However, fender gap and suspension clearance depend on the tire width, but not the track width.

See my post here.

Going from ET40 to ET27 in the rear will increase the rear track by 26mm.
In the front, going from ET29 to ET27 will increase the front track by 4mm.

[JoeFromPA]

Originally Posted by CanAutM3

You are correct, track width is an important element to consider to maintain the suspension geometry. However, fender gap and suspension clearance depend on the tire width, but not the track width.

See my post here.

Going from ET40 to ET27 in the rear will increase the rear track by 26mm.
In the front, going from ET29 to ET27 will increase the front track by 4mm.

Thanks for this. I'm considering an ET40 wheel and will likely want to install 12mm spacers front and rear in order to keep track width near stock.

[mkoesel]

Originally Posted by CanAutM3

I am not sure I follow here...

I have always understood that track width is dependent on wheel offset (ET) only and has little to do with wheel or tire widths. Track width is the distance between the centerlines of the left and right wheels/tires on a given axle, therefore only the offset impacts the position of the wheel centerlines relative to the hubs (with zero camber).

You're right - I was considering the outside edge of the tire, not the centerline.

Regarding geometry, it's not clear to me why suspension geometry would be optimized to the tire centerline. That is to say, I have a hard time understanding why - for example, say - a 225mm tire on the rear using a wheel that maintained track width would be better than - again, just for example - a 255mm tire that widened it. After all, by widening the track appropriately (namely 10mm per side) the 255mm tire will maintain the outside plane of the 275mm tire while still coming closer to the inside plane of the 275mm tire than 225mm tire does. How could the 225mm tire possibly be doing one thing better for the car's handling than the 255mm tire in this case?

I acknowledge that taking the 225mm tire and pushing it so far out that it's outside edge sits where the 275mm tire does wouldn't be so good at all since you are talking a 25mm decrease in offset which I have to imagine is going to hammer the wheel bearings and carriers.

BMW's own winter wheels clearly attempt to maintain outside tire edge near stock setup (within a couple mm). There's got to be a real good reason why they do that instead of maintaining track, right?

[milpar34]

Need to make a decision. I currently have the OEM 19s on my M3 and I live in the DC area. Have it narrowed down to the following options:

1) BMW OEM M Double Spoke 640M w/Continental Winter Contact TS830P 255/40 18" incl. TMPS for $2,890

2) VMR V721-GunMetal Grey with Bridgestone Blizzak LM-32 255/35/19 incl TMPS for $2,438

Thoughts, suggestions?

[CanAutM3]

Originally Posted by mkoesel

You're right - I was considering the outside edge of the tire, not the centerline.

Regarding geometry, it's not clear to me why suspension geometry would be optimized to the tire centerline. That is to say, I have a hard time understanding why - for example, say - a 225mm tire on the rear using a wheel that maintained track width would be better than - again, just for example - a 255mm tire that widened it. After all, by widening the track appropriately (namely 10mm per side) the 255mm tire will maintain the outside plane of the 275mm tire while still coming closer to the inside plane of the 275mm tire than 225mm tire does. How could the 225mm tire possibly be doing one thing better for the car's handling than the 255mm tire in this case?

I acknowledge that taking the 225mm tire and pushing it so far out that it's outside edge sits where the 275mm tire does wouldn't be so good at all since you are talking a 25mm decrease in offset which I have to imagine is going to hammer the wheel bearings and carriers.

BMW's own winter wheels clearly attempt to maintain outside tire edge near stock setup (within a couple mm). There's got to be a real good reason why they do that instead of maintaining track, right?

My understanding:

The cumulative forces applied on a tire more or less equate to a single vector applied on the longitudinal centerline of the wheel, this is why suspension geometry is designed around that point (see image below).

Offset changes the steering "scrub" radius on the front axle. This imapcts the level of grip the front tire can generate when turned and also impacts steering feedback and feel.

Further, offset can also affects suspension stiffness through the suspension's motion ratio. With less offset, the wheel's leverage about the inboard lower control arm pivot increases while the suspension spring/damper leverage remains constant. The net effect is a reduction in the effective wheel spring/damper rate.

I am not sure how much work BMW has put in it, but I figure they played with offsets on the winter wheel/tire packages to re-balance the suspension system according to the change of grip and sidewall stiffness of the winter tires. There might even be some compromises for esthetics too.

That being said, small changes in offset should not make drastic differences in handling even if they are not "optimal".

[JoeFromPA]

Be curious if a tire or suspension engineer could chime in on how much change in offset is really negligible, and at what threshold it creates issues on a ~3500 pound vehicle.