[timber511]

Installed uuc front swaybar couple month ago. bodyroll has been reduced
a lot. I went to the track last week. I do find the understeering problem.
did some research on the internet and decide to put the rear swaybar on it.
i pick M3 SWAYBAR becuase i can still keep the warranty on my car. order the parts from getbmwparts.com. it costs me total 225 canadian dollar including the shipping. installation cost me another 200 dollar since they have to lower the rear subfarme.

review

Bodyrolling almost gone
understeering has improved
handing ---day and night difference

even though it costs me $425 ,but it worth the money.

[Tee212]

how much was labor?

[henry418]

I'd get this mod if labor was cheaper ... (dropping subframe) can't really justify for that labor price.

[pits200]

What other suspension mods do you have? And do you notice if the ride is much harsher?

[shonuff]

Just to confirm: did you remove the UUC front swaybar? I remember reading a post by Doyle saying the UUC front swaybar was too stiff and actually caused more understeer (when compared to the rear swaybar alone).

P.S Also in Toronto and interested where you got the install done.

[Lenaxia]

Theoretically, adding only the rear swaybar produces an almost perfectly balanced car. The UUC rear sway will be closer to neutral and the M3 rear sway will have a little bit of oversteer. Adding anything other than the stock front sway will again revert to a understeer bias in our XI's.

If you want a car with 0 understeer and 0 oversteer, you should either go all stock + UUC rear sway, or M3 rear sway with spacers/staggered in back.

I will be upgrading both my suspension and rear sway at the same time sometime this year, I will be doing M3 rear sway with spacers.

[timber511]

Originally Posted by shonuff

Just to confirm: did you remove the UUC front swaybar? I remember reading a post by Doyle saying the UUC front swaybar was too stiff and actually caused more understeer (when compared to the rear swaybar alone).

P.S Also in Toronto and interested where you got the install done.

i still keep the front swaybar on the car

[timber511]

Originally Posted by henry418

I'd get this mod if labor was cheaper ... (dropping subframe) can't really justify for that labor price.

labour cost me $200

[timber511]

Originally Posted by pits200

What other suspension mods do you have? And do you notice if the ride is much harsher?

I have HR COILOVER ON MY CAR

[shonuff]

Originally Posted by Lenaxia

Theoretically, adding only the rear swaybar produces an almost perfectly balanced car. The UUC rear sway will be closer to neutral and the M3 rear sway will have a little bit of oversteer. Adding anything other than the stock front sway will again revert to a understeer bias in our XI's.

If you want a car with 0 understeer and 0 oversteer, you should either go all stock + UUC rear sway, or M3 rear sway with spacers/staggered in back.

I will be upgrading both my suspension and rear sway at the same time sometime this year, I will be doing M3 rear sway with spacers.

Nice, I plan on doing the same sometime soon. The e92 xi comes with 18's staggered stock so wouldnt that mean changing to a square setup if remaining stock with the UUC rear sway? I plan to go stock staggered 18s with M3 rear sway.

[Lenaxia]

Originally Posted by shonuff

Nice, I plan on doing the same sometime soon. The e92 xi comes with 18's staggered stock so wouldnt that mean changing to a square setup if remaining stock with the UUC rear sway? I plan to go stock staggered 18s with M3 rear sway.

No. UUC Rear sway with staggered will be fine. It will just have a slight bit of understeer which is probably a good idea. You prob won't even feel it unless you're tracking your car.

I'd take the money you'd otherwise spend on new wheels and put into the bilstein/swift suspension solution that's coming out for us soon. Were going for performance first here, looks second

[kdiggz]

Originally Posted by Lenaxia

put into the bilstein/swift suspension solution that's coming out for us soon

anymore info on this? i haven't heard of this myself

[Lenaxia]

Posted some info here:

http://www.e90post.com/forums/showpo...52&postcount=3

[yakev724]

A DIY for rear subframe bushings and rear sway would be nice. As I understand it, a special tool is required for the bushings, but might as well do both at once if going through with the work already...

[Lenaxia]

As much as I'm a DIY kinda guy, I think my limit is doing my suspension my self. I'm going to have someone else do the rear subframe. I'm hearing it taking up to 4+ hours even for people who actually know what they're doing not because its difficult but because its just a plain pain in the ass.

Not too keen on something like that. Difficult is one thing, pain in the ass is... well... a pain in the ass.

[kdiggz]

Originally Posted by Lenaxia

Posted some info here:

http://www.e90post.com/forums/showpo...52&postcount=3

oh, so it's just springs. i thought it was like a whole new complete suspension setup that was coming. fyi, dinan springs are linear as well

[MeeTsenPu]

Originally Posted by Lenaxia

Theoretically, adding only the rear swaybar produces an almost perfectly balanced car. The UUC rear sway will be closer to neutral and the M3 rear sway will have a little bit of oversteer. Adding anything other than the stock front sway will again revert to a understeer bias in our XI's.

If you want a car with 0 understeer and 0 oversteer, you should either go all stock + UUC rear sway, or M3 rear sway with spacers/staggered in back.

I will be upgrading both my suspension and rear sway at the same time sometime this year, I will be doing M3 rear sway with spacers.

Are you assuming M3 rear bushings as well with the M3 rear sway bar and stock bushings with UUC rear sway?

[Lenaxia]

Originally Posted by MeeTsenPu

Are you assuming M3 rear bushings as well with the M3 rear sway bar and stock bushings with UUC rear sway?

Actually I'm assuming stock bushings for both because I haven't been able to find deflection numbers for the M3 rear bushings. Then again I haven't looked all that hard yet.

@kdiggz Yeah, a complete suspension would be awesome, but its probably not going to happen, at least at a price point reasonable for a non-tracked DD. The Bilstein B8 Sprints + Swift Springs should run about 1k total for all parts, much more reasonable than anything else offered. We'll have to wait and see what spring rates Swift puts on the e9x springs, after that I'll call Bilstein to see if revalves of their shocks are needed.

Also, duly noted that dinan are also linear but they also cost an arm and a leg, not to mention they only swap out the rear struts. Dinan is only worth it if you want the badge or have too much money to blow.

Eibach, H&R and KW's are all progressive springs which are actually detrimental to getting power to the ground for XI's as we lose traction in front.