[Bimmerius]

looking for OEM+ suspension options, got a 2010 328xi with 81k miles recently currently at 86k and feels little soft floaty..

I'm not looking to lower the car nor do I want a very stiff ride but I do appreciate good handling.. (had a 2011 328xi couple of years ago -wifes car- that was a lease so never got lots of miles and remember stock suspension was ok -wife then got an F30 and this was the reason I purposely looked to get an e90.. well that is a different story..

so I have been searching and reading many threads, and my thought is this:

get the B4 Bilstein OEM replacements (they are supposedly 10% stiffer than stock?) so since current struts/shocks are tired and softer than new these B4's should feel worlds better?

have read on some threads where some got the B6 (HD) and experienced ride height increase?? hope not the case with B4?

Also, what else should I really be changing at the same time, shock mounts or anything else mandatory?

thanks!

[cpie168]

Subscribed. Thanks.

[cdgatti]

The B6 bilsteins can raise the ride height a little, about 1/2" when you first install them and then about 1/4" after they settle. The ride/handling/performance improvement with the BMW stock springs is excellent. If you can't handle the slight height increase, the B4 would be an improvement over what you have now for the reasons you stated, but not in the same league as the B6 units. Another option might be the Koni yellows, they would be more similar to the B6 for performance, but without the height increase since they use lower gas pressure.

[cpie168]

Hi cdgatti. You seem very knowledgeable on Bilstein shocks. I have the m-sport suspension on my E90. Would the B8's be my best bet if I want to keep using the m-sport springs rather than getting the B12 Pro-kit? How does the performance compare to the B6?

[cdgatti]

cpie - bilstein recommends the B6 for both the sport and non-sport oem bmw springs. Others on here have used the B8 successfully with the oem sport springs like you have, the only difference would be a slightly lower ride height, the B6 and B8 struts/shocks are valved identically, only the B8 units are shorter, you would just have slightly less suspension travel with the B8. the B8 units are recommended with lowering springs like H&R, eibach etc.

[cpie168]

Thanks for the insight cdgatti! Aren't the OEM M-Spory springs considered lowering springs since they represent a noticeable drop from non-M-Sport? And why would the shocks affect ride height? I thought it's the job of the springs to determine the ride height; that the shocks are only there to dissipate the energy as the springs are returned to their original height after going thru a bump?

Thanks again!

[Bimmerius]

Originally Posted by cdgatti

The B6 bilsteins can raise the ride height a little, about 1/2" when you first install them and then about 1/4" after they settle. The ride/handling/performance improvement with the BMW stock springs is excellent. If you can't handle the slight height increase, the B4 would be an improvement over what you have now for the reasons you stated, but not in the same league as the B6 units. Another option might be the Koni yellows, they would be more similar to the B6 for performance, but without the height increase since they use lower gas pressure.

Thanks, I'll probably do the B4 then, wouldnt mind 1/2 or 1/4 drop but not raise..

[cdgatti]

Originally Posted by cpie168

Thanks for the insight cdgatti! Aren't the OEM M-Spory springs considered lowering springs since they represent a noticeable drop from non-M-Sport? And why would the shocks affect ride height? I thought it's the job of the springs to determine the ride height; that the shocks are only there to dissipate the energy as the springs are returned to their original height after going thru a bump?

Thanks again!

The 'm-sport' are the same as 'sport' springs. If you have an x drive, there is no such thing as oem sport springs. The sport package is the seats/steering wheel and badging, no suspension changes. If you have the rwd coupe, they all have the sport suspension, whether they have the seats or not.

The B6 bilsteins can add some ride height because of the upward pressure they exert at rest, they are boosting the springs a little, so the weight of the car at rest doesn't compress the springs as much.

[cpie168]

Thanks cdgatti. Mine is a E90 RWD sport suspension. I guess B8 is my choice then, as I don't want ride height to increase.

[cdgatti]

yep others have gone with the b8 with the stock sport springs. you won't have to worry about any of the bumpstop issues with other options, the bilstein struts will have the bumpstops internal to the strut and the rear shocks will come with their own specifically designed bumpstop for the application.

[CJ421]

Originally Posted by Bimmerius

Thanks, I'll probably do the B4 then, wouldnt mind 1/2 or 1/4 drop but not raise..

Just verify what others are recommending works with an XI.

[Stream]

Can't recommend B4 - thay are even not as good as stock shocks.
Go with Koni (STR or FSD) for standart suspension or with Koni_Sport \ Bilstein_B6 with sport suspension.

[cpie168]

Stream, wouldn't the B6 raise the ride height per cdgatti's comments above?

B6 "raise in ride height" is a non-issue IMO. If you were that worried about fender gap, you would have filled it with taller tires or considered going with non-sport springs by now. If it's that big of a deal, look into lowering perches for the front, or just find some cheap oem sport springs, etc. and pair them with the Bilsteins.

Either way, I don't say this often when it comes to aftermarket parts but these Bilsteins are what these cars should have been equipped with from the factory. They obviously aren't the BEST dampers on the planet, but certainly make this car drive as it should have off the showroom floor.

[AdamN52]

Originally Posted by CJ421

Just verify what others are recommending works with an XI.

Interested to know this as well

[cdgatti]

Originally Posted by FCobra94

B6 "raise in ride height" is a non-issue IMO. If you were that worried about fender gap, you would have filled it with taller tires or considered going with non-sport springs by now. If it's that big of a deal, look into lowering perches for the front, or just find some cheap oem sport springs, etc. and pair them with the Bilsteins.

Either way, I don't say this often when it comes to aftermarket parts but these Bilsteins are what these cars should have been equipped with from the factory. They obviously aren't the BEST dampers on the planet, but certainly make this car drive as it should have off the showroom floor.

+1 - The very minimal height increase incurred with the B6 should be a non-issue. You will quickly forget about it as you enjoy many K miles of blissfull motoring, never worrying about shocks again on this car.

[E93M3-08]

Originally Posted by Bimmerius

looking for OEM+ suspension options, got a 2010 328xi with 81k miles recently currently at 86k and feels little soft floaty..

I'm not looking to lower the car nor do I want a very stiff ride but I do appreciate good handling.. (had a 2011 328xi couple of years ago -wifes car- that was a lease so never got lots of miles and remember stock suspension was ok -wife then got an F30 and this was the reason I purposely looked to get an e90.. well that is a different story..

so I have been searching and reading many threads, and my thought is this:

get the B4 Bilstein OEM replacements (they are supposedly 10% stiffer than stock?) so since current struts/shocks are tired and softer than new these B4's should feel worlds better?

have read on some threads where some got the B6 (HD) and experienced ride height increase?? hope not the case with B4?

Also, what else should I really be changing at the same time, shock mounts or anything else mandatory?

thanks!

I installed B6's on my 2006 e91 with non-sport suspension and I couldn't be happier. Whatever minimal amount the suspension was raised by is insignificant IMO and is probably offset by the slight sag of the original springs. The thrust exerted by the shocks due to gas pressure is no more than roughly twenty pounds force each.

The ride is "firm" and very controlled with much less noticeable body roll. I no longer live in fear of pothole explosions.

When replacing the shocks I also replaced the Guide support, lower part - item 6 on the "Rear Axle Suspension" diagram, and on diagram "Rear Axle with Suspension" item 5 "Rubber mount". While you're down there, check item 3 "ball joint" for wear or stiffness due to corrosion (this is NOT a bushing, but an honest to god ball joint and should swivel smoothly with minimal resistance - no squeaking allowed!).

Up front, item #1, guide support, is probably due for replacement. If not, replace it anyway as well as item #2 nuts. Check items 10 and 13 for damage and replace as necessary. You don't need any of the bellows or bump stops as they come with the B6's - not sure about the B4's.

Make sure you check part numbers using your car's VIN. The images are provided for illustration purposes only and part numbers for your car might be different.

[Stream]

Originally Posted by cpie168

Stream, wouldn't the B6 raise the ride height per cdgatti's comments above?

B6\B8 will raise front a bit (maybe 5mm). But new tophats will raise car too (5mm) but will settle later. Differences in height won't be noticeble after settling (after ~month).

I was not clear. B8 is recommended for Sport suspension and B6 for standard. But B6 also works fine with sport.

[Bimmerius]

so I was ready to order the B4 Bilstein but looks like the front right strut is on back order through aprox May

so starting thinking of Koni FSD.. from what I've read so far they can retain smoothness but also improve handling..

my main concern would be to reduce lift/squat during acceleration/braking but also if possible to somehow mitigate road crown.. (here is my crazy thought.. if dampers are stiffer so they reduce body lean then perhaps the car wouldn't be as prone too lean on one side driving straight on -the side with the road crown?)

my other concern is I read FSD's wear faster getting softer?

decisions... plus I already ordered a set of ContiDWS (replacing Michelin pilot AS3 as rears are about 2-3/32 though fronts still ok at 6/32) but would rather wait to do suspension before tires.

Appreciate any thoughts comments about FSD - thanks!