Best suspension upgrade that maintains ride quality

[E13]

I’m looking for the best suspension upgrade that maintains OEM ride quality. In an ideal world I’d go Ohlins, but unless I get a steal on those, they’re gonna be way out of my budget. My other thoughts were: koni yellow, koni FSD, bilstein b12, Kw comfort, and bilstein b8. If anyone has had experience with any of these, especially in New England, I would love to hear about it. I can’t drop the car too much, as I take it to go skiing. Thank you all in advance

[Josh-PA]

I did B6s on my e88 and have been really happy with them. Slightly stiffer than OEM, but equal/improved crashiness over bumps and noticably better handling (compared to my 100k mile OEMs ) I can't compare them to other options, but I am satisfied with the upgrade / cost.

[Wazowski]

I put Koni Yelliws on my e88 at 150k miles (currently 207k). I adjusted the rears to about 95% firmness. Fronts adjusted to maybe 70%. Love the ride. Only other suspension upgrade are White line RSFBs.

[blue135]

Went with Koni FSD and really like the ride. Unfortunately, or fortunately BMW introduced a 6MT Z4. So I have not had opportunity to push the set up, but ride is slightly better than OEM

[E13]

Unless anyone is selling their Ohlins, I’m stuck between four options. Koni FSD, Koni yellow, Bilstein b6, or Bilstein b8 with BMWPS springs.
I would replace all mounts and bushings too while I’m at it

If anybody has any insight into these, I would love to hear it

[cerealwars]

What is your use case? Is your suspension worn out, or are you dissatisfied with functional stuff?

I refreshed my entire suspension when I got my base model 128i a few years back. Bought some sport springs off a member here, converted my whole car to a sport package, mechanically speaking. New replacement Bilstein dampers and all new OEM mounts, plus Dinan camber plates.

I daily my car. I'm in it for 2+ hours at least three days a week, with a good amount of Detroit surface streets. I find the suspension to be pretty much perfect in terms of blending comfort and athleticism. I haven't tried other options, but I have zero desire to firm up the ride any more, and I push my car pretty good through the corners on the regular. Only things I would change are adding more camber and maybe tuning with sway bars.

Other recommendations - sport seats and RSFB inserts. I really think these are an absolute must on this car.

[Blau]

Bilstein PSS9 coilovers

[E13]

Originally Posted by cerealwars

What is your use case? Is your suspension worn out, or are you dissatisfied with functional stuff?

I refreshed my entire suspension when I got my base model 128i a few years back. Bought some sport springs off a member here, converted my whole car to a sport package, mechanically speaking. New replacement Bilstein dampers and all new OEM mounts, plus Dinan camber plates.

I daily my car. I'm in it for 2+ hours at least three days a week, with a good amount of Detroit surface streets. I find the suspension to be pretty much perfect in terms of blending comfort and athleticism. I haven't tried other options, but I have zero desire to firm up the ride any more, and I push my car pretty good through the corners on the regular. Only things I would change are adding more camber and maybe tuning with sway bars.

Other recommendations - sport seats and RSFB inserts. I really think these are an absolute must on this car.

Suspension is shot, I’d like to keep do something a little OEM+, which is harder with the 135i since it’s already on the sport suspension. I know anything new will be a big upgrade already, but I would like a sportier feel, or at least as much as a sporty feel that I can get without killing the ride quality

[spidertri]

If I was redoing suspension with ride quality as the main goal, I would not use Bilstein products. I've run them on 3 different cars and they always increase harshness, even when using the stock springs.

Out of your list, I would expect Koni FSD would maintain the ride quality and the others would be harsher. I don't have personal experience running them though.

My car had Koni yellows and eibach springs on it when I bought it. The previous owner had cranked the yellows all the way up and they crashed over bumps. Once I turned them down they were a lot better but still more sport than comfort.

[ShocknAwe]

If you want factory ride quality but better performance stick with something like BMWP springs and Koni FSD or the Bilstein B4 factory replacement shocks. Then do M3 front camber arms and rear guide rods, stiffer front sway bar with stock bar in rear unless you have a LSD and M3 rubber RSFBs. Avoid the M3 tension strut that will have a NVH adder that you will notice. Likewise do not install M3 differential bushings, that will add significant NVH.

Do not get Koni yellows or Bilstein B6/8/+ or lowering springs if you want factory comfort.

Something else that helps with comfort is tire sidewall. Stick with 18" wheels or even going to 17" wheels for more tire. Tire selection also matters, hankook and conti are typically softer than Michelin for example.

[E13]

Originally Posted by ShocknAwe

If you want factory ride quality but better performance stick with something like BMWP springs and Koni FSD or the Bilstein B4 factory replacement shocks. Then do M3 front camber arms and rear guide rods, stiffer front sway bar with stock bar in rear unless you have a LSD and M3 rubber RSFBs. Avoid the M3 tension strut that will have a NVH adder that you will notice. Likewise do not install M3 differential bushings, that will add significant NVH.

Do not get Koni yellows or Bilstein B6/8/+ or lowering springs if you want factory comfort.

Something else that helps with comfort is tire sidewall. Stick with 18" wheels or even going to 17" wheels for more tire. Tire selection also matters, hankook and conti are typically softer than Michelin for example.

What would an OEM+ set up look like? I’ll look into those M3 parts, are there any downsides to them? I’ve heard conflicting thoughts on the B8, some say they are a life changer and more comfortable, while others say they’re harsher. I’m just so lost

Noteworthy point, my cars dampers are pretty shot, so my “OEM” rode quality is already lower than usual. My thought process was that despite b8s being stiffer, they would actually work as a damper, making the overall comfort better

What’s a camber arm? Is that the same as a control arm?

Ok so what I’m hearing here: m3 control arms, m3 rear guide arms, front sway bar (won’t that increase understeer?), and oem like dampers. So no rear arm kit? Like the 6 piece one?

[E13]

So I guess new question here. With $2000 and shot dampers, what would you do to increase performance as much as possible without adding NVH?

[ShocknAwe]

Yes the front lower control arm.

What I gave you is the best bang for your buck set of changes to make.

Rear guide rods are the biggest difference other than toe arms, and you can't use the M3 toe arm.

[E13]

Originally Posted by ShocknAwe

Yes the front lower control arm.

What I gave you is the best bang for your buck set of changes to make.

Rear guide rods are the biggest difference other than toe arms, and you can't use the M3 toe arm.

Awesome. I appreciate it. Looks like BMWPS aren’t even made anymore, is there a recommended spring for a sportier feel or are m sports the best bang for your buck. Are the rear guide arms linear bearings? Will that soften up the rear too much? Apologies for all the questions. Suspension is the biggest make or break and I wanna get it right

[ShocknAwe]

Quick search turned this up.

https://www.getbmwparts.com/p-e82-1-...e82perfsprings

[tracer bullet]

Originally Posted by E13

Suspension is shot

Random thing to consider, is that even if you went to a totally new OEM suspension, it's going to feel a lot different than a shot suspension. I swapped struts all around on my 10 year old X3 to OEM and it took me a while to stop wondering if I'd bought the wrong struts, given how much stiffer everything was. Of course after a week or two I was completely used to it, realized it wasn't at all harsh, and it was actually why I liked the X3 to start with - that it had some semblance of handling and road feel compared to the competition at that time.

Anyhow, doing anything at all is going to be pretty great, and might even feel overly stiff at first. Even the "least" sporty option (OE equivalent) might still be a pretty great change and be what you're looking for. Maybe not of course, but I'm just suggesting keep the idea in mind when comparing, that OE might actually be a decent level.

[gjm120]

Originally Posted by E13

Unless anyone is selling their Ohlins, I’m stuck between four options. Koni FSD, Koni yellow, Bilstein b6, or Bilstein b8 with BMWPS springs.
I would replace all mounts and bushings too while I’m at it

If anybody has any insight into these, I would love to hear it

I have BMWP springs and Koni yellows. It is a bit harsh as mentioned, but I think for me most of that is from the M front control arms.

I'm really please with the overall handling of my car.

[E13]

Originally Posted by ShocknAwe

Quick search turned this up.

https://www.getbmwparts.com/p-e82-1-series-bmw-performance-springs-bundle-set-of-4-e82perfsprings

I’ll see if they have those in stock. I know the rears aren’t made anymore.
Ok so I hear a lot of people saying the b8 might be too stiff, especially considering how sloppy the car is now.
Would something like the Koni FSD with BMWPS be a nice middle ground? Are the FSDs a performance improvement compared to the b4 (stock)?

[blue135]

I view the FSD as "better" than stock. But then I am comparing to a suspension that had 75K miles. And I am pretty sure the FSD is still a compromise between ride and handling. I am also pretty sure that shocks I chose in the 90s (Bilstein of Koni Yellows depending on car) would not be acceptable to me now.
Your judgement is what counts.

[E13]

Originally Posted by blue135

I view the FSD as "better" than stock. But then I am comparing to a suspension that had 75K miles. And I am pretty sure the FSD is still a compromise between ride and handling. I am also pretty sure that shocks I chose in the 90s (Bilstein of Koni Yellows depending on car) would not be acceptable to me now.
Your judgement is what counts.

So the FSD is still sportier than stock? If so then I think I might get those, seeing that I’ve heard very few complaints about the NVH.

[blue135]

One way of viewing this is that Koni has three offerings, their "Street", FSD, and the adjustable yellows.
My experience is that the FSD is sportier than stock, but closer to the stock than to the Yellows I have had in the past.

[mkeiser]

it's definitely worth researching the technology behind FSD https://group.koni.com/products/car/fsd

I think it sounds right up your alley.