[RedKloud]

My suspension story:

Unfortunately when I got my 340i Xdrive last year, I got it with the standard suspension. While the ride quality was pretty good, it had too much body roll and floatiness. After much research on this forum I installed Dinan springs with Bilstein B8s 2 months back.This setup has improved the cornering a lot, but the ride quality has obviously deteriorated with the stiffer shocks. I don't mind the stiffer setup, but the suspension is also quite bouncy and just doesn't have the composure you'd expect of a car at this price point. So, I'm caught in a dilemma right now: should I go back to the OEM setup and accept the body roll and poor cornering? Would upgrading to coilovers such as the Bilstein B16 improve the ride quality?

[CruzM3]

Might be that the springs don't go well with the dampers. They need to be matched to each other.

[Polo08816]

Originally Posted by RedKloud

My suspension story:

Unfortunately when I got my 340i Xdrive last year, I got it with the standard suspension. While the ride quality was pretty good, it had too much body roll and floatiness. After much research on this forum I installed Dinan springs with Bilstein B8s 2 months back.This setup has improved the cornering a lot, but the ride quality has obviously deteriorated with the stiffer shocks. I don't mind the stiffer setup, but the suspension is also quite bouncy and just doesn't have the composure you'd expect of a car at this price point. So, I'm caught in a dilemma right now: should I go back to the OEM setup and accept the body roll and poor cornering? Would upgrading to coilovers such as the Bilstein B16 improve the ride quality?

Originally Posted by Cruz28/40

Might be that the springs don't go well with the dampers. They need to be matched to each other.

It's exactly because the springs didn't go well with the dampers.

This is the downside when people mix and match, and find out it doesn't handle as they expected it to.

[cfm56d7b]

Originally Posted by Cruz28/40

Might be that the springs don't go well with the dampers. They need to be matched to each other.

Bilstein B16 Coilovers feature 10-stage adjustments but each adjustment (click) will tune both rebound and compression. While it's perfectly fine, there isn't a way to tune rebound and compression individually.

KW V3 Coilovers feature 16-stage rebound and 12-stage compression adjustments; both can be tuned individually. You might want to ask fellow forum members about their experience tuning rebound and compression settings on KW V3 coilovers.

Either Bilstein B16 or KW V3 Coilovers will lower your vehicle by at least 30mm.

[RedKloud]

Originally Posted by cfm56d7b

Bilstein B16 Coilovers feature 10-stage adjustments but each adjustment (click) will tune both rebound and compression. While it's perfectly fine, there isn't a way to tune rebound and compression individually.

KW V3 Coilovers feature 16-stage rebound and 12-stage compression adjustments; both can be tuned individually. You might want to ask fellow forum members about their experience tuning rebound and compression settings on KW V3 coilovers.

Either Bilstein B16 or KW V3 Coilovers will lower your vehicle by at least 30mm.

Thanks. I remember you installing KW Street Comforts on your 335 xDrive. How was your experience? Did you experience any bounciness?

[cfm56d7b]

Originally Posted by RedKloud

Thanks. I remember you installing KW Street Comforts on your 335 xDrive. How was your experience? Did you experience any bounciness?

I thought KW Street Comfort coilovers were almost perfect for my needs as a daily driver: did not want to lower the vehicle (needed extra ground clearance), no body roll / floating symptoms, rebound only adjustments sufficient.

I don't believe KW Street Comfort Coilovers are available for 2016 340i xDrive vehicles yet. But one never knows. Call KW to confirm availability.

By the way, Bilstein B16 Coilovers are also an excellent product. It all depends how much do you prefer the flexibility of individual rebound and compression adjustments.

[CruzM3]

Originally Posted by cfm56d7b

Bilstein B16 Coilovers feature 10-stage adjustments but each adjustment (click) will tune both rebound and compression. While it's perfectly fine, there isn't a way to tune rebound and compression individually.

KW V3 Coilovers feature 16-stage rebound and 12-stage compression adjustments; both can be tuned individually. You might want to ask fellow forum members about their experience tuning rebound and compression settings on KW V3 coilovers.

Either Bilstein B16 or KW V3 Coilovers will lower your vehicle by at least 30mm.

I was responding to why his current setup was not working. I understand that coil over or adjustable bilsteins would work better.

[cfm56d7b]

About why the current setup may not work - very good point. Although some forum members were happy with different springs and shocks combinations, I am not a big fan of mismatched springs and shocks either. One of the more common symptoms: stiffer springs with softer shocks will lead to a bouncy ride. The Suspension forum has many threads about this topic.

[RedKloud]

So, will switching to coilovers make a difference or not really?

[cfm56d7b]

Originally Posted by RedKloud

So, will switching to coilovers make a difference or not really?

It will definitely make a difference.

[CntryClub007]

Originally Posted by RedKloud

So, will switching to coilovers make a difference or not really?

It will be a catastrophic improvement. If you want great handling, I've always believed in coilovers, not strut/spring combos. If you wanted to go crazy, you could do coilovers as well as sway bars. Will corner on rails then.

I always liked the initial response and predictability of coilovers vs. strut/spring combo.

[RM7]

Originally Posted by RedKloud

So, I'm caught in a dilemma right now: should I go back to the OEM setup and accept the body roll and poor cornering? Would upgrading to coilovers such as the Bilstein B16 improve the ride quality?

I'm not sure why everyone goes to springs and shocks to counter body roll. Springs and shocks help marginally, while turning the entire ride harder (requiring more damping). Anti-sway bars are specific to body roll, that's what their purpose is in life. Replace anti-sway bars with thicker. There is the stiffer translation of bumps from left to right, but it doesn't wreck the entire ride, while significantly dialing out body roll. If anything, you still might need some better shocks to better dampen the effects of harder cornering, but but just going springs or shocks to "dial out body roll" doesn't seem like the right way to fix the issue, definitely not based on stiffer sways in my last few cars.

[bbog2008]

OP, what tires and rims are you running on?

If you are still on RFT's there is not setup there that can improve the ride quality. Also if you are running on 19" rims that could be another issue.
If you have regular non RFT's you need to play with the tire pressures a bit to find the sweet spot.
I have this setup on my car and is really really good.

[cfm56d7b]

Very helpful discussion about how anti-sway bars work:

http://speed.academy/how-swaybars-work/

There is much more to anti-sway bars than just choosing aftermarket anti-sway bars. Softer front / stiffer rear anti-sway bars can eliminate understeer as an example. It's important to know what your tuning objectives are.

I still think the most practical sequence of steps is 1) install coilovers (if coilovers are preferred), 2) let the suspension settle, evaluate suspension behavior after driving for a few weeks, and 3) consider anti sway bars with understeer / oversteer considerations in mind.

[Polo08816]

Originally Posted by JamesNoBrakes

I'm not sure why everyone goes to springs and shocks to counter body roll. Springs and shocks help marginally, while turning the entire ride harder (requiring more damping). Anti-sway bars are specific to body roll, that's what their purpose is in life. Replace anti-sway bars with thicker. There is the stiffer translation of bumps from left to right, but it doesn't wreck the entire ride, while significantly dialing out body roll. If anything, you still might need some better shocks to better dampen the effects of harder cornering, but but just going springs or shocks to "dial out body roll" doesn't seem like the right way to fix the issue, definitely not based on stiffer sways in my last few cars.

I'm convinced the springs/shocks vs. sways debate may be going on with people with different configurations.

I can see the xDrive vehicles (except for M240ix) requiring thicker anti-sway bars.

I'm not convinced that's the solution for RWD cars with the Sport Suspension which already has thicker sway bars. This is consistent with the M Performance Suspension which includes sway bars if one is upgrading from base suspension, but is basically just a matched spring/shock combo for those who already have the Sport suspension.

[RM7]

Originally Posted by Polo08816

I'm convinced the springs/shocks vs. sways debate may be going on with people with different configurations.

I can see the xDrive vehicles (except for M240ix) requiring thicker anti-sway bars.

I'm not convinced that's the solution for RWD cars with the Sport Suspension which already has thicker sway bars. This is consistent with the M Performance Suspension which includes sway bars if one is upgrading from base suspension, but is basically just a matched spring/shock combo for those who already have the Sport suspension.

OP has a 340ix though, meaning he can't get sport-suspension. He can try to emulate it, with thicker anti-sways, lower (stiffer) springs and shocks to match. Except for what you mentioned, there is no such thing as "sport suspension" on 3 and 4 series x-drives. Audi does it. BMW doesn't do it.

[raybolic]

Originally Posted by RedKloud

My suspension story:

Unfortunately when I got my 340i Xdrive last year, I got it with the standard suspension. While the ride quality was pretty good, it had too much body roll and floatiness. After much research on this forum I installed Dinan springs with Bilstein B8s 2 months back.This setup has improved the cornering a lot, but the ride quality has obviously deteriorated with the stiffer shocks. I don't mind the stiffer setup, but the suspension is also quite bouncy and just doesn't have the composure you'd expect of a car at this price point. So, I'm caught in a dilemma right now: should I go back to the OEM setup and accept the body roll and poor cornering? Would upgrading to coilovers such as the Bilstein B16 improve the ride quality?

I installed B16 on my F32 428i RWD and here's little feedback.

When cornering, you'd feel minimal body roll and feels like the car is well planted on the ground. As others mentioned there's 10 clicks from softest to hardest. I used 6 front 5 rear and this is perfect for me.

Note that if you want a tuck, these coilovers can't go that low. At lowest setting I'm at 3/4 finger gap (at least for the F32). DO PAY ATTENTION on the part number you're ordering, as there's two versions of B16 with one being comfort version (little higher ride and overall meant to be street use) and other is standard version.

KW v3 seems to be the choice if you want absolute control of height / dampening, but I believe B16 is cheaper.

p.s. if you're running M bumper with a lip, I guarantee you will be scratching everywhere with B16 at lowest setting as is. Again, this is for F32 RWD not F30 xDrive

[Big Nodge]

The KW Street Comfort coilovers work for the 340xi, I'm running them with Dinan sways. KW confirmed they are compatible a while back. I love how my car handles, but I am getting some creaking from the rear that I haven't gotten around to diagnosing yet. I think it's probably the end links (stock) or swaybar bushings.

[RedKloud]

Originally Posted by bbog2008

OP, what tires and rims are you running on?

If you are still on RFT's there is not setup there that can improve the ride quality. Also if you are running on 19" rims that could be another issue.
If you have regular non RFT's you need to play with the tire pressures a bit to find the sweet spot.
I have this setup on my car and is really really good.

I have non-RFTs on 19" rims. I have lowered the tire pressures, and it improves the bounciness, but the steering becomes more mushy.

[RedKloud]

I have decided to go back to stock suspension. Appointment has been made for next week.

[goj]

Originally Posted by CntryClub007

It will be a catastrophic improvement. If you want great handling, I've always believed in coilovers, not strut/spring combos. If you wanted to go crazy, you could do coilovers as well as sway bars. Will corner on rails then.

I always liked the initial response and predictability of coilovers vs. strut/spring combo.

Not to be that guy but "catastrophic" in no way describes an improvement

[Sidewinderpb]

Originally Posted by goj

Not to be that guy but "catastrophic" in no way describes an improvement

Hahaha - I was reading through hoping to find this comment