Originally Posted by mweisdorfer

Bilstein B4's are about 10% stiffer than stock. The sport version of that will be more than 10%.

Says who?

Originally Posted by EdmJunky

Now these last two posts have sent me down another path of uncertainty though. I was dead set on the B6's until reading mweisdorfer's and Spitfire007's posts.

Dude, don't puss out. For every 1 negative you read about B6s/B8s you'll read 10 more that sing their praises.

Keeping things in perspective, the previous poster drives his car around Brooklyn and NYC...well no shit it's going to ride rough! As if the stock junk underdamped shocks/struts would handle those conditions any better. Wrong car entirely for that intended purpose IMO.

Not to mention, the B4s and FSDs are crap...if you haven't seen enough bad reviews lately to completely strike them off your list yet then you aren't researching hard enough.

If you want to lower the car, either do it now or don't do it at all. My vote is that you go Dinan as other options seem all but pointless in comparison...either that or maybe find some low mile OEM Sport springs. Or better yet, just have chris@strutmonkey put either option together for you to avoid the headache; especially since you seem so stressed out about this entire process for some reason.

Also, if you don't want to go full M3 control arms up front, just do the M3 lower arm to freshen up that piece (while also adding some much needed camber) and go with the Meyle upper arm instead. It's a full rubber bushing that's stiffer than stock (so no future leaks) but isn't as stiff as the M3 piece (less NVH, etc.).

[mweisdorfer]

Originally Posted by FCobra94

Says who?

Dude, don't puss out. For every 1 negative you read about B6s/B8s you'll read 10 more that sing their praises.

Keeping things in perspective, the previous poster drives his car around Brooklyn and NYC...well no shit it's going to ride rough! As if the stock junk underdamped shocks/struts would handle those conditions any better. Wrong car entirely for that intended purpose IMO.

Not to mention, the B4s and FSDs are crap...if you haven't seen enough bad reviews lately to completely strike them off your list yet then you aren't researching hard enough.

If you want to lower the car, either do it now or don't do it at all. My vote is that you go Dinan as other options seem all but pointless in comparison...either that or maybe find some low mile OEM Sport springs. Or better yet, just have chris@strutmonkey put either option together for you to avoid the headache; especially since you seem so stressed out about this entire process for some reason.

Also, if you don't want to go full M3 control arms up front, just do the M3 lower arm to freshen up that piece (while also adding some much needed camber) and go with the Meyle upper arm instead. It's a full rubber bushing that's stiffer than stock (so no future leaks) but isn't as stiff as the M3 piece (less NVH, etc.).

I think the OP keeps mentioning "comfort" over performance a lot. However, the OP wants performance too. Problem is you can't have both when you go to extremes, especially like a B12 Kit etc.

This is why I suggested a B4 sport. He'd get a set up that has some performance but still have some comfort too.

[Spitfire007]

I think It's important to keep something in mind. These cars were engineered to use runflat tires so they're over sprung and underdamped, the sub frames and subframe bushings are engineered softer and more compliant, and to use softer shocks to compensate for harder tires.
Switching to non-runflats helps.
Compensating for softer tires by adding stiffer shocks, also helps. But then you've changed two major components without changing anything else.

The problems are the compromises that must be made to keep the car comfortable yet performing well.

The E90 Platform is simply not that comfortable a car. Period. The e46 was better. The stock e38 was amazing (handled better than my e90)

Yes I drove my car in and around New York City and Brooklyn. I'm now in PA.
I had B6s specifically installed, WITH ALL NEW HARDWARE AND MOUNTS AND RUBBER, also because they are much tougher (less deflection) not just because they are stiffer and to help protect the rest of the car from damage (bottoming out for example) due to the poor road conditions.

But even with multiple long road trips south north east and west, I can positively assure you that I cringe every time I approach a bump pothole or highway expansion joint.
This is even with the softer Continental DWS06 tires on stock 17s.

B6s Are sublime on smooth roads. But the simple fact is America's roads are mostly crappy, especially in the Northeast. If the original poster wants sportiness and comfort, I think the best one could achieve would be to remain with the stock sport suspension. Going any stiffer, or adding stiffer M3 components will transmit a lot more noise vibration and harshness through the car to the driver and its occupants.

Having had B6s on multiple cars over the last 12 to 15 years, I enjoy their performance I enjoy the cornering and the stability in breaking, but it comes at a not insignificant cost in comfort. Just something to keep in mind.

Originally Posted by Spitfire007

I think It's important to keep something in mind...

Very well said and I agree 100%...but, just like you mentioned, there are multiple factors that go into the "harshness" of a damper; not just the stiffness level of the struts/shocks themselves.

Perfect example; I'm currently riding on oversized DWS tires and B6s w/ stock springs. When tire pressure is set to 30 psi or below, the ride is soft and almost squishy at times; especially during the hot/humid months.

A week or two back I upped the pressures to 32 psi all around though. That one small change makes it feel like a completely different car. Expansion joints and potholes are indeed cringe-worthy given the stiffer tire; especially on days where temps are less than ~50*. Best way to describe it is like the difference between setting the KW coilovers in my old car (Civic) from 50% stiff to 75% stiff; it made that much of a change.

So yeah, little things make a big difference; whether it be stiffer bushings or a change in tire pressure/height/compound/etc. Each is all user dependent though so, as always, YMMV.

[Spitfire007]

And the DWS is a soft and squishy tire...imagine Michelin AS3s....ran those for 4 years and handling was laser like...I was very disappointed in the DWS initially. Have gotten used to them, but still don't think the slight comfort increase is worth the serious increase in vagueness and slow response...

[cranelec]

Originally Posted by EdmJunky

Ok so I took another look over the weekend. The front upper control arm bushings are done on both sides so those will need replacing, the rest of the bushings looked fine so I may or may not be servicing those.

Now these last two posts have sent me down another path of uncertainty though. I was dead set on the B6's until reading mweisdorfer's and Spitfire007's posts. The B6's were my choice because I read from other posts that they were similar ride comfort as the B4's but without the body roll. Now I'm unsure and having a hard time choosing between the b4's, b6's, and now the Koni FSD's as I read these are best for ride comfort although durability is shotty (but they do have lifetime warranty if I understood correctly).

I may also be adding Eibach Pro Springs for stance, not sure if this will change the shock/strut combo I should go with. Again, my main focus is ride comfort for daily driving in town and on highways.

TLDR: Koni FSD's are great for 30k miles on Northeast PA roads.
Three years ago, @ 85K miles, 07 328xi I installed KONI FSD dampers (front & rear). Additionally, I purchased and installed the ECSTUNING front and rear damper installation kit.
FRONT: except for the OEM sport springs, I replaced thrust arms, lower control arms, ball joints, inner and outer tie rods with OEM (Meyle or Leomforder)
REAR: just the Koni FSD dampers with the ECS hardware.
Car was a goddamn dream to drive until this past January.
The Pennsylvania Department of Transportation road maintenance was nonexistent this past winter.
The left front factory sport spring simply broke into three pieces. Surprisingly, the FSD damper is ok (according to my local BMW. Dealership)
Unfortunately, my right rear FSD damper is toast (according to my local BMW. Dealership).
IMHO...The Koni FSD's provided me with nearly 30k miles of true driving enjoyment.