[Nickco43]

I just recently picked up a 17 540i with standard non etc shocks. While the car is comfortable (as comfortable as it could be on factory 20s), I find the car is way too floaty, especially while driving in the mountains.

Does anyone have recommendations for suspension solutions that still retain the cars comfort but control the body roll? I was thinking of installing a set of none EDC Bilstein B6 shocks.

Thoughts?

[ppointer]

I have B6 on my '01 M Roadster. I have B4 on a couple other BMWs. Using stock springs in all cases. The B6 definitely provides a more sophisticated drive, according to my butt. However, I cannot say they will deliver what you are looking for. My roadster is certainly comfortable, more so than with stock struts / shocks. The car also worked very well last time I took it through Deal's Gap.

[G30M]

Originally Posted by Nickco43

I just recently picked up a 17 540i with standard non etc shocks. While the car is comfortable (as comfortable as it could be on factory 20s), I find the car is way too floaty, especially while driving in the mountains.

Does anyone have recommendations for suspension solutions that still retain the cars comfort but control the body roll? I was thinking of installing a set of none EDC Bilstein B6 shocks.

Thoughts?

M5 antiroll bars?

[430Scud]

Originally Posted by G30M

M5 antiroll bars?

Thicker anti roll bars will have virtually no impact on ride. They only come into play when cornering hard. Same with the M5 chassis "X" brace. It stiffens the chassis, but only is felt when corning hard. No change to ride quality.

[430Scud]

Originally Posted by Nickco43

I just recently picked up a 17 540i with standard non etc shocks. While the car is comfortable (as comfortable as it could be on factory 20s), I find the car is way too floaty, especially while driving in the mountains.

Does anyone have recommendations for suspension solutions that still retain the cars comfort but control the body roll? I was thinking of installing a set of none EDC Bilstein B6 shocks.

Thoughts?

Have you ridden in a car with B6 struts and shocks before? What types of cars are you comparing the ride to?

B6 will make the car handle very well, but understand that comes with a cost, in a much firmer ride that many like and some may not. That firmer ride also can allow the car to pick the occasional buzz or rattle more easily that with the stock suspension. I've modded a few cars suspension in the past and while I always enjoyed the changes, my passengers sometimes complained.

Bilstein in general (B6, B8, PSS), tend to have more compression damping that other brands which is why they ride firmer (harder). Koni makes a great product and the compression damping is a tad softer. Some prefer Koni because of that. Both will have much firmer rebound damping that stock.

[Neusser]

Originally Posted by Nickco43

I just recently picked up a 17 540i with standard non etc shocks. While the car is comfortable (as comfortable as it could be on factory 20s), I find the car is way too floaty, especially while driving in the mountains.

Does anyone have recommendations for suspension solutions that still retain the cars comfort but control the body roll? I was thinking of installing a set of none EDC Bilstein B6 shocks.

Thoughts?

Normally Bilstein Sport or a set of Konis and drop tire pressure to just above 2 bar. US tire pressures are near full load spec., which is terrible for handling in a vehicle that is not fully loaded.

Since you have standard springs, you'd be better off getting a set of 704 springs, too, or a set of lowering springs that keep the suspension within stock geometry (anything around 1-2 cm).

[Alscoob]

I've just fitted AC Schnitzer springs to my G31 with adaptive & x-drive, real improvement, not floaty at all. I was horrid in comfort mode before the change, like an old boat, not anymore though, you can tell it's now attached to the tarmac. Okay on mine it drops the ride height by 20mm, but then the adaptive sits much higher than standard. The ride height on ACS springs depends on the model so some lower more than others.

To compare, my last F31 was on standard M sport springs and did the ACS spring change on that, I appreciate that it's not the same car but the suspension was similar to yours (not adaptive). On that car it was a great improvement too, if anything it felt more comfortable to drive but when you pushed it ... it stayed planted. That dropped the front by 15mm and the rear by 10mm.

In my conversations with ACS they did say that the dampers on the 5er were good which is why they don't / didn't offer their own as part of a suspension tune. So maybe it's not the dampers you need to change but the springs?
By comparison the dampers on the 3er were awful and I changed those to ACS as well.

[ChiNorm]

I just had a set of B6 shocks installed. It's a huge improvement. Good luck.

[Neusser]

Originally Posted by ChiNorm

I just had a set of B6 shocks installed. It's a huge improvement. Good luck.

This is the way!

[DaWhole9]

MSS Springs...stock dampers. No diff in ride quality...improved handling...all "floatiness" is gone.

[jcy]

have you tried lowering tire pressure by a couple of psi?

[Neusser]

Originally Posted by jcy

have you tried lowering tire pressure by a couple of psi?

I mention this often. The pressures on these cars are too high--even the half load spec. 2-2.1 bar removes almost all of the float, helps the chassis stay planted in transitions, and even the comfort steering setting has some real steering feedback. Plus tire wear is evened out.

Shock upgrade can help with the somewhat weak rebound damping (common to most stock OEM shocks on German cars).


Pressures keep creeping up to meet efficiency regulations.

[Nickco43]

Originally Posted by 430Scud

Have you ridden in a car with B6 struts and shocks before? What types of cars are you comparing the ride to?

B6 will make the car handle very well, but understand that comes with a cost, in a much firmer ride that many like and some may not. That firmer ride also can allow the car to pick the occasional buzz or rattle more easily that with the stock suspension. I've modded a few cars suspension in the past and while I always enjoyed the changes, my passengers sometimes complained.

Bilstein in general (B6, B8, PSS), tend to have more compression damping that other brands which is why they ride firmer (harder). Koni makes a great product and the compression damping is a tad softer. Some prefer Koni because of that. Both will have much firmer rebound damping that stock.

My last car, a E92 M3, had none EDC B6 shocks fitted to it. The handling was exceptional but the ride quality around town was a little firmer than I would have liked it.

I just really miss my F10 that was on 18in wheels and had Bilstein B4 sport shocks. The suspension was firm enough to not feel like a boat and the tire sidewall could handle bumps in the road.

I think I will look into the Koni shocks and maybe add them on to my next service in the fall.

[JoeFromPA]

People often run to shocks/struts as a solution, but forget to look at the suspension as a system that starts with tire (and, by default, wheel), spring, strut/shock, bushings, and sway bars. (Yes you could get into chassis bracing too, but let's keep it simple for now)

First, do you have the type of tires on your car designed to give the feel you want? Are the air pressures dialed in? Tires alone can transform a car, including floatiness.

Next, do you have the right spring/strut for your goals? Springs aren't just ride height - they are the gross controller of how your car reacts to rebound/compression activities. After that is struts/dampers as the fine controller.

Last is bushings that can add ALOT of tightness into the system in exchange for NVH.

...

I'm doing this as a primer. At the end of the day, it's a 5 series. You can turn it into feeling like a go-kart at the expense of alot of money and NVH. if you just want to remove floatiness, start with tires and springs.

[G30M]

Originally Posted by JoeFromPA

People often run to shocks/struts as a solution, but forget to look at the suspension as a system that starts with tire (and, by default, wheel), spring, strut/shock, bushings, and sway bars. (Yes you could get into chassis bracing too, but let's keep it simple for now)

First, do you have the type of tires on your car designed to give the feel you want? Are the air pressures dialed in? Tires alone can transform a car, including floatiness.

Next, do you have the right spring/strut for your goals? Springs aren't just ride height - they are the gross controller of how your car reacts to rebound/compression activities. After that is struts/dampers as the fine controller.

Last is bushings that can add ALOT of tightness into the system in exchange for NVH.

...

I'm doing this as a primer. At the end of the day, it's a 5 series. You can turn it into feeling like a go-kart at the expense of alot of money and NVH. if you just want to remove floatiness, start with tires and springs.

hmm interestingly, i switched from 20" RFT staggered to 19" 255 squared non RFT and the suspension is working like it's designed to. no more crashing over hard surfaces, and unimaginably, no more boaty feeling. they must have tuned the car with non RFTs.

on that, proving what you say is correct.

[JoeFromPA]

Originally Posted by G30M

hmm interestingly, i switched from 20" RFT staggered to 19" 255 squared non RFT and the suspension is working like it's designed to. no more crashing over hard surfaces, and unimaginably, no more boaty feeling. they must have tuned the car with non RFTs.

on that, proving what you say is correct.

It's funny, people often assume one suspension (dampers, springs, bushings) is supposed to magically perform as the manufacturer designed equally across 3 different wheel sizes (i.e. 18x8, 18x9, 19x9, 20x10, etc.) and multiple different tire designs - from RFT/non-RFT as well as performance/summer. How on earth could a single suspension be optimized across massive differences in sidewall height, stiffness, and contact patch size? It can't.

[Neusser]

Originally Posted by JoeFromPA

It's funny, people often assume one suspension (dampers, springs, bushings) is supposed to magically perform as the manufacturer designed equally across 3 different wheel sizes (i.e. 18x8, 18x9, 19x9, 20x10, etc.) and multiple different tire designs - from RFT/non-RFT as well as performance/summer. How on earth could a single suspension be optimized across massive differences in sidewall height, stiffness, and contact patch size? It can't.

This is the issue with many things in the suspension world. Tire pressures from the factory are not optimized for performance, they are optimized to try and offer a balance of efficiency, wear, performance, etc. For keen drivers, this is bad.

Shocks and springs are also optimized for a variety of use cases on one vehicle, and, ofc, across wheel sizes.

In my experience, for sporty road driving, tire pressure and dampers are usually critical for those on stock suspension with BMWs and Mercs.

Stock sport springs are typically more than up to the job of most sporty road driving, and offer enough comfort for daily use. Back in my VW days, I recall that Eibach Prokit springs were actually tested as softer than the stock VW sport springs!