[joewalton]

We have body roll. We need a sway bar. Now.
We have body roll. We need a sway bar. Now.
We have body roll. We need a sway bar. Now.
We have body roll. We need a sway bar. Now.
We have body roll. We need a sway bar. Now.
We have body roll. We need a sway bar. Now.
We have body roll. We need a sway bar. Now.

It's a metal bar. Let's go already.

[Jamesons Viggen]

I have been stalking Turner.com for it's release

[joewalton]

Originally Posted by Jamesons Viggen

I have been stalking Turner.com for it's release

Let's take it to Kickstarter.

What's it cost to make a metal bar in China? $10? It's got to be the most necessary and anticipated sway bar in automotive history, no? Is there a car with more enthusiasts out there? A car that needs body roll reduced to restore it to its prior glory more? I'm sick of waiting, not like you can just drive up to Dick's Sporting Goods and buy one in a parking lot or anything.

[Jamesons Viggen]

Originally Posted by joewalton

Let's take it to Kickstarter.

What's it cost to make a metal bar in China? $10? It's got to be the most necessary and anticipated sway bar in automotive history, no? Is there a car with more enthusiasts out there? A car that needs body roll reduced to restore it to its prior glory more? I'm sick of waiting, not like you can just drive up to Dick's Sporting Goods and buy one in a parking lot or anything.

Yep, materials are cheap, under $20 in steel and packaging. The money comes from the R&D and freight lol.

[Teemo Panda]

Originally Posted by joewalton

Let's take it to Kickstarter.

What's it cost to make a metal bar in China? $10? It's got to be the most necessary and anticipated sway bar in automotive history, no? Is there a car with more enthusiasts out there? A car that needs body roll reduced to restore it to its prior glory more? I'm sick of waiting, not like you can just drive up to Dick's Sporting Goods and buy one in a parking lot or anything.

Haha, you crack me up Joe!

[joewalton]

Originally Posted by Teemo Panda

Haha, you crack me up Joe!

We need a sway bar. Give it to us.
We need a sway bar. Give it to us.
We need a sway bar. Give it to us.
We need a sway bar. Give it to us.
We need a sway bar. Give it to us.
We need a sway bar. Give it to us.

I feel a little bit better now.

[IM2C]

I'm sure BMW will charge $299

[AMJAM]

BMW M Performance has your answer

[Jamesons Viggen]

Originally Posted by AMJAM

BMW M Performance has your answer

They do not offer swaybars, only that you use 704 Sport bars if your car is not a Sport/MSport to start with.

[AMJAM]

Ah ok I have the M Sport so I guess I already have them

[KK328]

Originally Posted by Jamesons Viggen

They do not offer swaybars, only that you use 704 Sport bars if your car is not a Sport/MSport to start with.

What's the difference between sport bars and sway bars?

[Jamesons Viggen]

Originally Posted by KK328

What's the difference between sport bars and sway bars?

Same. Both swaybars, the sports bars are specific to the MSport/Sport 704 suspension and are larger in diameter.

[KK328]

Originally Posted by Jamesons Viggen

Same. Both swaybars, the sports bars are specific to the MSport/Sport 704 suspension and are larger in diameter.

Thanks

[M.Suka]

These cars need sway bars asap! miss my Hotchkis sways on my E46, by far the best suspension mod ever for me.

[Kauro]

Argh, still waiting for someone to release this!!!

[rallybull]

Trying to understand here. I have the regular "non-sport" suspension.

• Does that car not come with some sway bar already?
  
• What would be the driving behavior if I just added a new (after market) sway bar without doing a full coilover (like M-Perf suspension)? If this itself takes care of body roll, isn't this option a bang-for-the-buck to reduce body roll without having to spend a lot on a full coil over?
  
• What would be the behavior behavior if just did a full coilover (some after market one that does not come with a sway bar) without adding/changing the default sway bar ?

EDIT: I'm actually not too dissatisfied with the stock suspension in the car. I can feel some amount of road, yet it is not too harsh (so I can go over bumps pretty fast without bottoming out). However I do notice the car has body roll which I would like to address without making the suspension too harsh.

[utenigma]

Originally Posted by tojo_m

• Does that car not come with some sway bar already?

Both standard and sport have front and rear sway bars

Std suspension front sway is 25/21.1 mm, Sport suspension front sway is 25/22.2mm
Std suspension rear sway is 12mm, Sport suspension rear sway is 13mm

Sport and M-perf suspension sways are the same

Originally Posted by tojo_m

• What would be the driving behavior if I just added a new (after market) sway bar without doing a full coilover (like M-Perf suspension)? If this itself takes care of body roll, isn't this option a bang-for-the-buck to reduce body roll without having to spend a lot on a full coil over?

Yes, that is the purpose of a sway bar - to tie the compression of one wheel to the other which reduces roll without stiffening the straight-line suspension characteristics. Seems like a Win-Win and every car should have GIANT sway bars to eliminate all roll - not quite. Wheels should be able to articulate somewhat independently. In the case one wheel encounters a bump, the larger the sway bar the more that bump is transferred to the wheel that didn't hit the bump. So extremely stiff sway bars will cause the vehicle to judder or skip when they hit a bump. So like everything in suspension design, it's a trade off

Originally Posted by tojo_m

• What would be the behavior behavior if just did a full coilover (some after market one that does not come with a sway bar) without adding/changing the default sway bar ?

Changing to a coil-over, changes the Spring and Strut, which alters the vehicle's compression and damping characteristics, which will (likely) make the car ride stiffer. It will also (likely) limit roll, due to higher spring rates (springs are harder to squish so car doesn't roll onto them) and (likely) lower vehicle height (car has less suspension travel so can roll less at the limit).

[Jamesons Viggen]

Originally Posted by tojo_m

Trying to understand here. I have the regular "non-sport" suspension.

• Does that car not come with some sway bar already?
  
• What would be the driving behavior if I just added a new (after market) sway bar without doing a full coilover (like M-Perf suspension)? If this itself takes care of body roll, isn't this option a bang-for-the-buck to reduce body roll without having to spend a lot on a full coil over?
  
• What would be the behavior behavior if just did a full coilover (some after market one that does not come with a sway bar) without adding/changing the default sway bar ?

EDIT: I'm actually not too dissatisfied with the stock suspension in the car. I can feel some amount of road, yet it is not too harsh (so I can go over bumps pretty fast without bottoming out). However I do notice the car has body roll which I would like to address without making the suspension too harsh.

Swaybars directly address body roll and are the bang for the buck suspension modifications.

[AMJAM]

Isn't installing sway bars on the F30 quite a serious undertaking? I am sure I read somewhere on here that someone upgraded to the m performance suspension and had to upgrade the sway bars to the m sport one and it involved quite an amount of work

[Jamesons Viggen]

Originally Posted by AMJAM

Isn't installing sway bars on the F30 quite a serious undertaking? I am sure I read somewhere on here that someone upgraded to the m performance suspension and had to upgrade the sway bars to the m sport one and it involved quite an amount of work

Rear sways are typically easy to install. The fronts are hard work.

I have the 704 Sport setup, won't be touching the front bar.

[rallybull]

Originally Posted by utenigma

[/list]
Both standard and sport have front and rear sway bars

Std suspension front sway is 25/21.1 mm, Sport suspension front sway is 25/22.2mm
Std suspension rear sway is 12mm, Sport suspension rear sway is 13mm

Sport and M-perf suspension sways are the same



Yes, that is the purpose of a sway bar - to tie the compression of one wheel to the other which reduces roll without stiffening the straight-line suspension characteristics. Seems like a Win-Win and every car should have GIANT sway bars to eliminate all roll - not quite. Wheels should be able to articulate somewhat independently. In the case one wheel encounters a bump, the larger the sway bar the more that bump is transferred to the wheel that didn't hit the bump. So extremely stiff sway bars will cause the vehicle to judder or skip when they hit a bump. So like everything in suspension design, it's a trade off



Changing to a coil-over, changes the Spring and Strut, which alters the vehicle's compression and damping characteristics, which will (likely) make the car ride stiffer. It will also (likely) limit roll, due to higher spring rates (springs are harder to squish so car doesn't roll onto them) and (likely) lower vehicle height (car has less suspension travel so can roll less at the limit).

Thanks! Looks like if bmw brings out just the upgraded roll bars, it would be enough for me. Not sure if spending $3000 on the M-Perf Suspension is really worth it since I will rarely track.

[oceanview]

Originally Posted by utenigma

[/list]Both standard and sport have front and rear sway bars

Std suspension front sway is 25/21.1 mm, Sport suspension front sway is 25/22.2mm
Std suspension rear sway is 12mm, Sport suspension rear sway is 13mm

Sport and M-perf suspension sways are the same

Regarding to the BMW online part catalogue, sway bars vary depending on the suspension variant (regular or M Sport) and also on the car type (F30/F31) and engine type.
Not looking at all the other models. But it seems there is quite a bunch of sway bars on the different F30/F31 models
(I hope, I did read that correctly in the online catalogue.)

335i F30 regular Suspension = Sway Bar 25mm/21.2mm Part# 31 35 6 792 118
335i F30 M Sport Suspension = Sway Bar 25mm/22.2mm Part# 31 35 6 792 119
335i F31 all Suspension = Sway Bar 25mm/22.2mm Part# 31 35 6 792 119

328i F30 regular Suspension = Sway Bar 24mm Part# 31 35 6 792 124
328i F30 M Sport Suspension = Sway Bar 24.2mm Part# 31 35 6 792 125
328i F31 all Suspension = Sway Bar 24mm Part# 31 35 6 792 124

316i F30 regular Suspension = Sway Bar 24mm Part# 31 35 6 792 111
316i F30 M Sport Suspension = Sway Bar 24.6mm Part# 31 35 6 792 112
316i F31 all Suspension = Sway Bar 24mm Part# 31 35 6 792 111

As far as I know, sway bars are made out of feather steel. I don't know if the 328i sway bar just varies in size, or if it's also another (harder) type of feather steel that's beeing used for the M Sport Suspension Sway Bar. (or will just 0.2mm more thikness make any difference? )

I don't know if the sway bar of a 335i would fit on a 328i (maybe someone else can answer that), but if so, that's maybe worth giving it a try for 328i owners complaining about body roll.