[dazzab]

Gooday,

What is the FIRST modification I should make to reduce body roll on my 330i?

Would antiroll bars be as effective as stiffer springs or lowered springs?

Or should I just dive straight down the new damper / lowered springs road?

Interested in all your comments.

[geoff2010]

antiroll bars are going to be the best bang for the buck... not sure if the e90 330 already has them from the factory.

after that, i would say coilovers.

[Ghunger]

My understanding is sway bars actually reduce traction on the inside tire where stiffer springs don't. Seems like I remember reading somewhere that bimmers tend to do better with stiffer springs and not as well with real stiff sway bars. You might think about emailing someone like turner motorsport or another group like that for suggestions. They have a lot of race experience with E46's and I'd guess the E90 setup would be similar.

[longtran]

rear sway bar with stifin it up. springs and dampers will help.

[ae8t6ix]

Like stated anti-roll bars are the way to go if your looking to reduce body roll. Lowering will help because stiffer springs will reduce the amount of compression that occurs during cornering loads, however it really doesn't do much on the opposite end where your suspension wants to lift. Sways will reduce the amount your car will want to lift thus keeping all four wheels down to handle whatever spirited driving you feel. Good luck.

[HRC]

Originally Posted by longtran

rear sway bar with stifin it up. springs and dampers will help.

I too support the rear-bar only opinion.

Danny

[18LLC]

make 4 wheels in the rear, like the truck. that should be the best way to reduce the body rolling. not kidding.




but i know you won't do it. as everyone else said, sway bar will help.

[ksfrogman]

Sway bars do transfer weight from the inside wheels of a turn to the outer wheels. It effectively increases the spring rate on the side being compressed since it links the left and right sides of the car.

Two advantages of minimizing body-roll:

(1) Maintains composure of the car as it limits lean, and center of gravity. The lack of suspension compliance could be a disadvantage when the car hits a bump on rough pavement. That's why certain vehicles (e.g., BMW 7-series) use active anti-roll bars.

(2) Minimizes positive camber of the outer wheel that usually occurs when the car leans to that side. Therefore, the weight-bearing tire has more of its contact patch maintained.

[dazzab]

Thanks for all feedback.

I too thought that anti-roll bars would be the best starting point but, apparantly not.

As Ghunger suggested I contacted a well known BMW tuner and their advice was:

1. To reduce roll the cars centre of gravity needs to be lowered.

2. Springs / coliovers are the best starting point.

3. Anti-roll bars can then be fitted if required.

4. They recommend anti-roll bars are NOT fitted to BMWs with standard suspension as it stresses the stock components too much.

So it's a new coilover set with 25mm lower sport springs for me!

[SV Concepts]

Originally Posted by dazzab

2. Springs / coliovers are the best starting point.

Absolutely. This will probably be sufficient, too.
Call or visit online for the best pricing on:
H&R, Eibach, Bilstein
www.jlevisw.com

Thanks!
JL

[Josh49]

Jlevi - Any idea when a rear sway bar will be released for the e90 325xi. I called around no one has it yet. Not on H&R's website either..