[izaazk]

I've been researching for a while now and read many threads but no concrete support for the question...

I have an RWD F30 with m adaptive (58K miles) thats bouncing and bottoming out frequently..

I want a floored look (not that honda cambered crap) just no wheel gap ..

I live in a city with crazy pot holes and road crevices etc.. comfort is very important... so is ride height because i need enough clearance in the snow

So... I am considering BC BR coilovers for now which allow height adjustability independent of shock height...

Or should i look into a shock / spring package (Bilstein b6 + lowering springs?)

[cfm56d7b]

Without going into excessive details, to achieve comfortable ride you are looking the suspension needs to have individually adjustable dampen / rebound controls. Comfortable ride is achieved by tuning the suspension to your preferences.

This means more expensive coilovers such as KW V3.

[Stlthnmrdrd]

bc br with swift springs work just fine. With proper setup u can make a bc coilover ride like kw, but the build quality wont be as good as kw.

[Logicoeur]

Originally Posted by Stlthnmrdrd

bc br with swift springs work just fine. With proper setup u can make a bc coilover ride like kw, but the build quality wont be as good as kw.

The build quality is just as good as KW. Maybe not the stock BC springs, but with Swift springs that doesn't matter.

[Logicoeur]

Originally Posted by izaazk

I've been researching for a while now and read many threads but no concrete support for the question...

I have an RWD F30 with m adaptive (58K miles) thats bouncing and bottoming out frequently..

I want a floored look (not that honda cambered crap) just no wheel gap ..

I live in a city with crazy pot holes and road crevices etc.. comfort is very important... so is ride height because i need enough clearance in the snow

So... I am considering BC BR coilovers for now which allow height adjustability independent of shock height...

Or should i look into a shock / spring package (Bilstein b6 + lowering springs?)

Look at KW Street comforts. They will give you exactly what you are looking for. The rear dampening adjuster is on the top, however. So you would have to remove the shock to adjust it.

The Bilstein PSS10 are a good alternative as all the adjusters are on the buttom of the shock. It's just that they are $700 more than the kw street comfort.

[N420i]

Any of the options that have been suggested, even the street comforts, are going to be significantly stiffer than the adaptive you now have even in comfort settings... And it's sort of unavoidable if the car is lowered.
Suspension travel is paramount to comfort. By lowering the car you're shortening the available suspension travel and the springs just HAVE to be stiffer to prevent bottoming out. If you wanna get rid of the wheel well gaps you're gonna have to drop by at least an inch. A whole inch of travel reduction is going to require reasonably stiff springs...
Also keep in mind that big drops eat stock shocks because they are forced to work outside of their engineered height continously... It's generally a good idea to swap shocks if dropping the car by anything around or over an inch...

[Logicoeur]

Originally Posted by N420i

Any of the options that have been suggested, even the street comforts, are going to be significantly stiffer than the adaptive you now have even in comfort settings... And it's sort of unavoidable if the car is lowered.
Suspension travel is paramount to comfort. By lowering the car you're shortening the available suspension travel and the springs just HAVE to be stiffer to prevent bottoming out. If you wanna get rid of the wheel well gaps you're gonna have to drop by at least an inch. A whole inch of travel reduction is going to require reasonably stiff springs...
Also keep in mind that big drops eat stock shocks because they are forced to work outside of their engineered height continously... It's generally a good idea to swap shocks if dropping the car by anything around or over an inch...

Not all coilovers shorten the suspension travel when lowering. BC coilovers haves shock body adjustment so this doesn't happen.

Others account for the shorter travel range with the springs and valving so there's no performance lost but "comfort" is still retained (eg. KW and Bilstein)

[BuefordTjustice]

Originally Posted by N420i

Any of the options that have been suggested, even the street comforts, are going to be significantly stiffer than the adaptive you now have even in comfort settings... And it's sort of unavoidable if the car is lowered.
Suspension travel is paramount to comfort. By lowering the car you're shortening the available suspension travel and the springs just HAVE to be stiffer to prevent bottoming out. If you wanna get rid of the wheel well gaps you're gonna have to drop by at least an inch. A whole inch of travel reduction is going to require reasonably stiff springs...
Also keep in mind that big drops eat stock shocks because they are forced to work outside of their engineered height continously... It's generally a good idea to swap shocks if dropping the car by anything around or over an inch...

Do you know this from experience? I have KW street comforts and although it's almost on the lowest setting, my ride and comfort is superior to my stock x drive springs.

[N420i]

Originally Posted by BuefordTjustice

Do you know this from experience? I have KW street comforts and although it's almost on the lowest setting, my ride and comfort is superior to my stock x drive springs.

Not from direct experience with street comforts on an F30, but general experience as I did work in a performance tuning shop for a few years.

If both the spring stiffness and suspension travel is reduced, there is a real risk of bottoming out hard and often.

Even if the spring is just as long, if the car is riding lower than stock the whole strut HAS to be shorter (as that's what determines ride height if we're ignoring top hat stack height or suspension arm geometry, which is beyond the scope of what's being discussed here) and thus there is less travel available for the wheel to move vertically over bumps.

Perhaps you don't get a lot of speed humps over in the US, but over here in Europe bottoming out is a real concern, and it's prevented by either riding high or installing stiff springs. This wouldn't be a concern over normal potholes as those aren't deep enough, but it would be on standard speed humps such as these:



or strong compressions.

[Logicoeur]

That's why the coilovers come with stiffer springs and valving. The suspension travel is accounted for that way.

[N420i]

Originally Posted by Logicoeur

That's why the coilovers come with stiffer springs and valving. The suspension travel is accounted for that way.

Certainly, and stiffer springs and valving lead to a harsher ride, not to greater comfort...

[Logicoeur]

Originally Posted by N420i

Certainly, and stiffer springs and valving lead to a harsher ride, not to greater comfort...

Not when they are paired correctly as in KW or Bilstein or even BC

[kern417]

Keep in mind that stiff doesn't mean harsh. Harsh is what I experienced with BCs. Stiff is what I experienced with KW. Yes all coilovers will be stiffer, but not necessarily harsh. And most people associate a stiffer ride with less ride comfort, so I agree it will degrade with any suspension designed to lower the car. You will feel bumps more and it takes smaller bumps for the car to become unsettled.

But for the best comfort, I also hear KW Street Comforts are as good as it gets. I have V1s and I like them, but the car definitely is stiffer than the stock non-adaptive m-sport suspension. So it's definitely stiffer than adaptive in comfort.

I wouldn't recommend BCs at all.

[cfm56d7b]

Adding a few more thoughts to the discussion.

Suspension travel has two priorities.

Compression - the quicker the compression cycle, the more comfortable the perception as the road imperfections are absorbed.

Rebound - the quicker the rebound, the more control (aka "sportiness") the driver experiences as the suspension geometry is maintained as quickly as possible.

That's why there individually controlled compression and rebound controls are always desired. However, some coilovers such as Ohlins optimized both cycles by design.

[JaredG_F30]

Ohlins road and track are adjustable from the bottom and do a great job at absorbing bumps and potholes

[MacklinUSOB]

Originally Posted by kern417

Keep in mind that stiff doesn't mean harsh. Harsh is what I experienced with BCs. Stiff is what I experienced with KW. Yes all coilovers will be stiffer, but not necessarily harsh. And most people associate a stiffer ride with less ride comfort, so I agree it will degrade with any suspension designed to lower the car. You will feel bumps more and it takes smaller bumps for the car to become unsettled.

But for the best comfort, I also hear KW Street Comforts are as good as it gets. I have V1s and I like them, but the car definitely is stiffer than the stock non-adaptive m-sport suspension. So it's definitely stiffer than adaptive in comfort.

I wouldn't recommend BCs at all.

Exactly.

Stiffness is a large element in ride comfort but isn't the end of the story. Many people are more comfortable in a car that may be more stiff but has improved body control to limit "float" sensations, myself included. On end of life 704 dampers I found ride quality worse than with the V2's. The excess up and down motion before the suspension would come to rest was enough to make me and passengers nauseous at times, I can only imagine this being more pronounced with heavier F3X variants, or those with xDrive.

Can't go wrong with the Street Comforts. Having the adjustibility is a nice cherry on top. The adjustment is really not difficult and I have done it just by loosening the top hat and compressing the shock until I can access the knob. What I really enjoy about it is that I can turn them almost all the way down when I swap winters on to have a more compliant ride for when the roads turn lunar.

BC's are not something anyone should be installing if they're after a comfortable or quiet ride. Have heard and felt first hand how harsh and noisy they can be.

[Logicoeur]

My only experience with BC was on my old A4. I did not see the stiffness or discomfort many complain about here. However I did upgrade to swift linear springs, new tophats, New rubber spring mounts, and poly spring washers out of the box.


I believe the noise people here complain about is the shock top mount. It seems to be metal top mount against the metal of the tophat. Seen a couple posts here about a complainnts of the same on KW coilovers, as well. I dont believe they use a rubber insert in the mount either?

[kern417]

Originally Posted by Logicoeur

My only experience with BC was on my old A4. I did not see the stiffness or discomfort many complain about here. However I did upgrade to swift linear springs, new tophats, New rubber spring mounts, and poly spring washers out of the box.


I believe the noise people here complain about is the shock top mount. It seems to be metal top mount against the metal of the tophat. Seen a couple posts here about a complainnts of the same on KW coilovers, as well. I dont believe they use a rubber insert in the mount either?

For me it was all because of the camber plates. I will never run them on a daily driver again because the spherical bearings wear and get noisy. It sounds like it's broken a lot of the time.

I'm still not sold on the swift spring thing, though i know it's a common upgrade for BC's. If it doesn't decrease the spring rate then I don't understand how it could make it more comfortable, but I know most people increase the spring rate to prevent rubbing. But as stated before, everyone's tolerance is different. On a track car, sure. But not on a car that spends 95% of it's time driving me to and from work. I'll find other ways to dial in the suspension geometry that are more compliant.

[Logicoeur]

Originally Posted by kern417

For me it was all because of the camber plates. I will never run them on a daily driver again because the spherical bearings wear and get noisy. It sounds like it's broken a lot of the time.

I'm still not sold on the swift spring thing, though i know it's a common upgrade for BC's. If it doesn't decrease the spring rate then I don't understand how it could make it more comfortable, but I know most people increase the spring rate to prevent rubbing. But as stated before, everyone's tolerance is different. On a track car, sure. But not on a car that spends 95% of it's time driving me to and from work. I'll find other ways to dial in the suspension geometry that are more compliant.

Do the F30 models come with a camber plate?

As far as the swift springs I believe they manufacture with much better metallurgy, and so they don't sag anywhere as soon as the stock BC springs. I do agree with everyone's tolerance differing though. They were my second set of coilovers ever. First one was a set of $300 coilovers equivalent to Racelands . Now those were HORRIBLE, so by comparisom it was a huge jump incomfort.

Planning to go PSS10 with this car anyhow

[kern417]

Originally Posted by Logicoeur

Do the F30 models come with a camber plate?

As far as the swift springs I believe they manufacture with much better metallurgy, and so they don't sag anywhere as soon as the stock BC springs. I do agree with everyone's tolerance differing though. They were my second set of coilovers ever. First one was a set of $300 coilovers equivalent to Racelands . Now those were HORRIBLE, so by comparisom it was a huge jump incomfort.

Planning to go PSS10 with this car anyhow

The BC coilovers do. They advertise the spherical bearings for performance (which they are great for) but ignore the fact that they are horrible for daily driving. That's why factory bearings like ball joints, axles, etc. come with boots to contain lubricants that reduce noise and extend the useful life.

My vote is to go with the camber-adjustable LCA bushings for a daily driver. Not as easy to adjust or install, but much more compliant and also provide improved performance.