BMW Performance Suspension is on! Brief Summary + Question!

[1SerieStud]

Hello all,

I just installed my BMW Performance Suspension today. The ride improved substantially, with reduce body roll, nose dive, and squat. I'm not going to elaborate a lengthy summary, as other members have done that already. I do want to mention though that the ride feels more planted and more responsive to steering input. I have a few questions for those who have installed this suspension though:

1) I am extremely picky, and as much as I tried to keep the kit cosmetically flawless, the spring compressors left some ugly rash on the yellow coating of the front springs. In some very minor areas, a little of the yellow was peeled off. It almost seemed like this yellow coating is not very thick/resistant, and there truly is no way other than using spring compressors, to install the front suspension. Unless of course, the entire front suspension is brought to the ground, but that wouldn't be practical and I don't know of many people that would do it that way. The question is, has anyone experienced this during installation, and will there be any repercussions as a result?

2) The kit came with a sway bar, and to the naked eye, this looked nearly identical to the one that came off the car. Is this bar that came with the kit really different? The car feels and handles different, but I am unsure if this is due to the springs/struts, or if the new sway bar has anything to do with it.

Thanks!

[1trip5]

the springs are fine. the finish on mine was already scrachted/chipped when they arrived at my doorstep. you'll get over it real fast, trust me.

the new bar does make a difference. the old bar reduces to a smaller diameter at the midpoint (necks down, lesser structural rigidity). The new bar is the same diameter throughout.

[1SerieStud]

Originally Posted by 1trip5

the springs are fine. the finish on mine was already scrachted/chipped when they arrived at my doorstep. you'll get over it real fast, trust me.

the new bar does make a difference. the old bar reduces to a smaller diameter at the midpoint (necks down, lesser structural rigidity). The new bar is the same diameter throughout.

Thank you for your input! Makes me feel better about it.

[1SerieStud]

Originally Posted by 1trip5

the springs are fine. the finish on mine was already scrachted/chipped when they arrived at my doorstep. you'll get over it real fast, trust me.

the new bar does make a difference. the old bar reduces to a smaller diameter at the midpoint (necks down, lesser structural rigidity). The new bar is the same diameter throughout.

Oh and I forgot to ask, how long does it take for the suspension to fully settle? The car does seem lower in all 4 corners already, but I'm not sure if it's been all 10mm already or if it still has to settle some more.

[Xaeryan]

Originally Posted by 1trip5

the springs are fine. the finish on mine was already scrachted/chipped when they arrived at my doorstep. you'll get over it real fast, trust me.

the new bar does make a difference. the old bar reduces to a smaller diameter at the midpoint (necks down, lesser structural rigidity). The new bar is the same diameter throughout.

The first part is true, my springs had fallen out of their "homes" in the shipping box, so they had plenty of battle scars right out of the box. You end up with more damage after using the spring compressors. It's a soft paint (they appear to be paint dipped?) and gets "paint dents" easily.

The latter part needs correction...
Both stock AND BMW performance sway have the same neck-down in mid-point. Essentially, they are IDENTICAL in diameter everywhere. The difference comes from an extra "S-bend" in the performance sway (take another look at both if you still have the stock one), which increases the stiffness of the bar by changing the effective lever arm ratio.
FWIW some of the M3 sway bars do not have the neck-down in the center, these may be what the previous poster was referring to.

[1SerieStud]

Originally Posted by Xaeryan

The first part is true, my springs had fallen out of their "homes" in the shipping box, so they had plenty of battle scars right out of the box. You end up with more damage after using the spring compressors. It's a soft paint (they appear to be paint dipped?) and gets "paint dents" easily.

The latter part needs correction...
Both stock AND BMW performance sway have the same neck-down in mid-point. Essentially, they are IDENTICAL in diameter everywhere. The difference comes from an extra "S-bend" in the performance sway (take another look at both if you still have the stock one), which increases the stiffness of the bar by changing the effective lever arm ratio.
FWIW some of the M3 sway bars do not have the neck-down in the center, these may be what the previous poster was referring to.

Thank you for posting as well, and I'm glad you did, because I thought I had seen the neck-down section on the new one, however, I was starting to think it had been my imagination. Yes I still have the old one, but the new one is on the car already so I cannot compare them side by side, but I do visualize what you just explained. Thank you!

Oh I just remembered that when installing the sway bar, there really isn't a way to center it other than by eye, so I'm hoping that by connecting the end links and then securing the 2 brackets in place the bar was centered. I also noticed the new rubber bushings were a PITA and did not want to give into the brackets unless forced by tightening the nuts.

[Xaeryan]

Originally Posted by 1SerieStud

Thank you for posting as well, and I'm glad you did, because I thought I had seen the neck-down section on the new one, however, I was starting to think it had been my imagination. Yes I still have the old one, but the new one is on the car already so I cannot compare them side by side, but I do visualize what you just explained. Thank you!

Oh I just remembered that when installing the sway bar, there really isn't a way to center it other than by eye, so I'm hoping that by connecting the end links and then securing the 2 brackets in place the bar was centered. I also noticed the new rubber bushings were a PITA and did not want to give into the brackets unless forced by tightening the nuts.

There's not much play side-to-side (none?), but any that there is will center itself through normal driving as long as you attached/tightened the end-links properly. Nothing to it. The bushings/brackets tend to be tough to get together; I used the same procedure as you. Some people have used C-Clamps to squeeze the brackets onto the bushings beforehand.

Don't overthink it; I'm sure you did fine - and get out there and enjoy it!

[1SerieStud]

Originally Posted by Xaeryan

There's not much play side-to-side (none?), but any that there is will center itself through normal driving as long as you attached/tightened the end-links properly. Nothing to it. The bushings/brackets tend to be tough to get together; I used the same procedure as you. Some people have used C-Clamps to squeeze the brackets onto the bushings beforehand.

Don't overthink it; I'm sure you did fine - and get out there and enjoy it!

Thank you...I tend to have some minor "OCD" moments when it comes to installing things on my car haha

[Xaeryan]

We all have bouts of OCD.

Settling doesn't take long at all; if you're wondering this for deciding when to get an alignment, a few days is probably more than enough. Today's springs are typically "pre-settled" by compressing them fully a few times, so it's more of a settling of your suspension. I.E. springs rotating until they are "locked" into the formed top-hats, strut perches mating properly, that kind of thing. If everything was mounted right during the install (most of the times this is the case), then a few bounces down the road is all you really need.

[1SerieStud]

Originally Posted by Xaeryan

We all have bouts of OCD.

Settling doesn't take long at all; if you're wondering this for deciding when to get an alignment, a few days is probably more than enough. Today's springs are typically "pre-settled" by compressing them fully a few times, so it's more of a settling of your suspension. I.E. springs rotating until they are "locked" into the formed top-hats, strut perches mating properly, that kind of thing. If everything was mounted right during the install (most of the times this is the case), then a few bounces down the road is all you really need.

Haha! Thanks again. The car feels superb on the road! Can't stop wanting to drive it all the time. Alignment to cone this Friday!

[1trip5]

interesting clarification on the sway bar above. i did not have the opportunity to study the two side by side and assumed the difference was the diameter. Thanks for setting the record straight.

my suspension took 2 days (1 hour driving per day) to completely settle. it lowered approx 12mm front and rear. The difference is slight but noticeable. All of my friends commented on the improved stance immediately.

[RimasRS]

You guys Lucky ones

[1SerieStud]

Originally Posted by RimasRS

You guys Lucky ones

lol why?

[1SerieStud]

Here is my 2-day update: WOW!

[1SerieStud]

For those with this suspension, I have another question:

I was washing my car yesterday, and while on my driveway I noticed that the right rear was a tad higher (probably less than a quarter inch difference) than the left rear. I'm hoping this had to do with the way the car was sitting on the driveway. Since then I don't seem to find a perfectly level surface to test it. Has anyone noticed any height difference from one side to the other? I made sure to install all components properly, and yesterday I double checked the boxes to make sure both rears had the same part number, since there are multiple sets of springs for this car.

[1SerieStud]

Originally Posted by 1SerieStud

For those with this suspension, I have another question:

I was washing my car yesterday, and while on my driveway I noticed that the right rear was a tad higher (probably less than a quarter inch difference) than the left rear. I'm hoping this had to do with the way the car was sitting on the driveway. Since then I don't seem to find a perfectly level surface to test it. Has anyone noticed any height difference from one side to the other? I made sure to install all components properly, and yesterday I double checked the boxes to make sure both rears had the same part number, since there are multiple sets of springs for this car.

Apparently the way it was sitting on the incline of my driveway. All looks good/even today whew!

[mosx]

Originally Posted by 1SerieStud

Apparently the way it was sitting on the incline of my driveway. All looks good/even today whew!

One of the big reasons I went with the PS. Every aftermarket spring I have put on a car has been uneven. Most won't notice it, but I always did ... OCD moment again. I was hoping that an OEM BMW part wouldn't have this problem, and I was right, it's damn near perfectly even all the way around.

[Dackelone]

Originally Posted by 1SerieStud

For those with this suspension, I have another question:

I was washing my car yesterday, and while on my driveway I noticed that the right rear was a tad higher (probably less than a quarter inch difference) than the left rear...

I noticed the same thing with my factory ride height on my 135i. The RR sits a tad higher (+6mm's) than the LR. Here is my post from the other day.

LF = 65.1 cm RF = 65.2 cm
LR = 64.2 cm RR = 64.8 cm


http://www.1addicts.com/forums/showthread.php?t=476941


Dackel

[1SerieStud]

Originally Posted by Dackelone

I noticed the same thing with my factory ride height on my 135i. The RR sits a tad higher (+6mm's) than the LR. Here is my post from the other day.

LF = 65.1 cm RF = 65.2 cm
LR = 64.2 cm RR = 64.8 cm


http://www.1addicts.com/forums/showthread.php?t=476941


Dackel

Interesting. At first I was concerned, but it turned out is was the way I had it parked for washing.

Maybe where your car spends most of its time parked has made it settle that way, who knows. I do know that suspension stance is very dynamic. Just like when the car is jacked up for extended periods of time it takes a while for it to settle, I'm sure if a car spends extended periods of time on an uneven surface, it needs time and a leveled surface to settle. This is just my theory.

[JB135MDCT]

Originally Posted by Xaeryan

There's not much play side-to-side (none?), but any that there is will center itself through normal driving as long as you attached/tightened the end-links properly. Nothing to it. The bushings/brackets tend to be tough to get together; I used the same procedure as you. Some people have used C-Clamps to squeeze the brackets onto the bushings beforehand.

Don't overthink it; I'm sure you did fine - and get out there and enjoy it!

If the sway bars have the same diameter, I assume the new bushings are for stiffness?

[JB135MDCT]

Originally Posted by 1SerieStud

Here is my 2-day update: WOW!

Did you have the M or Sport package option to begin with?

[Dackelone]

Originally Posted by 1SerieStud

Interesting...

Maybe where your car spends most of its time parked has made it settle that way, who knows...

I park my car in a level garage. It doesn't sit parked on any hills. I thought it was strange too - at first. I think if everyone would measire their ride height we would see that this is how the cars sit.