[BSM n54iS]

Originally Posted by solishe

Hi. Here is a cut/paste from a different thread that I posted to recently.

My Setup
I originally had the BMWPS V2 kit with all M3 front and rear control arms, M3 subframe bushings, Dinan rear upper shock mounts, and OE 287 18 inch wheels with Michelin PSS non runflats. I am basically running everything the same but now with Bilstein B8 Sport dampers instead of the BMWPS dampers.

Ride Height
With the BMWPS my distance from center of wheel cap to fender was about 13.25 inches to 13.35 inches on all 4 corners. It really was a perfect stance for my taste. With the Bilsteins and new strut mounts/spring pads, my ride height increased by about .4 to .5 inches in the front. So I installed SP lowering perches up front and now the car sits as it was before the change or just a touch lower.

Performance
Overall feel: I am really impressed with these dampers on springs that were not even used for their precise tuning (eibach pro kit springs were, the ones in the B12 kit). The 4 corners just feel more stable/solid and the rear feels more planted than with the BMWPS dampers. I don't know if it is the higher damping force (due to high pressure gas in monotube applications) that is responsible for this sensation, but it is noticeable (when compared to the BMWPS dampers). With the BMWPS dampers I used to have to run 35 PSI in front and 42 PSI in rear to achieve a more solid feel and much less play in the rear. With the Bilsteins, 33 PSI in front and 38 PSI feels best and more stable in the rear.

Acceleration/Braking/Hard Turning: Squat upon hard acceleration and dive upon hard braking are much less noticeable with the Bilsteins than with the BMWPS dampers (again probably because of the higher damping force as a result of higher pressure in the monotube). Also, on hard turning, the reduced roll has lessened the understeer sensation.

Performance over small bumps/imperfections (nvh): This is where the Bilsteins really shine when compared to the BMWPS dampers. They dampen the small imperfections in the road (ie road reflectors and very small bumps etc) very well. The ride comfort has increased with these Bilsteins. I got so used to the nvh of the BMWPS/m3 control arm combo that I did not realize I missed it. But I am very pleased with how well this monotube design keeps the high frequency/low amplitude vibrations away from me in the driver seat.

Performance over larger bumps or really bad roads: In this department it is a bit tougher for me to notice a difference in straight line performance. Maybe it is due to the high stiffness of the BMWPS yellow springs, but the combination of the high damping force and high spring rate is a rocky experience as the dampers attempt to dampen the larger spring deflections (perhaps it would be better with less stiff springs such as the eibachs, which the dampers were designed specifically for in the B-12 Pro Kit). But I would definitely say the Bilsteins are at least on par with the BMWPS dampers, and perhaps better due to cancelling out the nvh element of the larger bumps.

For $600 shipped for all 4 dampers with associated dust boots and Bumpstops included, this was a nice upgrade for me as I just kept my current PS springs. The car just rides like a newer car as the nvh is not as bad. Furthermore, my wiggly and unstable/somewhat disconnected feeling rear issue has been improved. And the bonuses of reduced dive/squat/hard-turning roll and general stability are nice bonuses.

This will be my last spring/damper combo. If I make another change, I will move on to quality coilovers most likely.

If I had to recommend a nice bang for buck spring/damper combo I would recommend the B12 kit over my setup. I have a feeling the B12 would be more comfortable than what I'm currently running (PS springs with B8s). I think the PS springs may be a touch too high on spring rate and the B12 would probably be a bit more comfortable as the B8 dampers were designed specifically for the eibachs in that kit (which have a lower spring rate than PS springs). But if one wants a stiffer ride, then I suppose the combo I'm running would suffice.

solishe Why did you decide to go with the B8 dampers over Koni Yellows for instance when upgrading? Do you think the Konis would have given that same .5" rise in ride height that the Bilsteins did?

[feuer]

Koni yellow matched with BMWPS and satisfied.

[BSM n54iS]

Originally Posted by feuer

Koni yellow matched with BMWPS and satisfied.

Hey yea I remembered you had the Koni's, how many miles have you put on them? The reliability from Koni to Bilstein is a point. Turner loves Bilstein, so I can't really tell how the damping would be matched on the B8 vs. the yellows

[feuer]

Originally Posted by BdSM n54iS

Hey yea I remembered you had the Koni's, how many miles have you put on them? The reliability from Koni to Bilstein is a point. Turner loves Bilstein, so I can't really tell how the damping would be matched on the B8 vs. the yellows

I have two cars with Koni yellows. One matched with Eibach Sport installed in 2010 with about 75k (still feel better than the 60k Suchs they replaced). Another matched with BMWPS installed in 2014 with about 25k. Regarding reliability of Koni compared to Bilstein I don't have personal experience on any on my cars. At the shop a lot of Bilsteins are getting replaced. Especially the regular black Bilstein. But they are a lot more cars with Bilstein to begin with. So that isn't an accurate comparasment either. Only issue with Koni is rust. I learned that with the 2010 setup. So coated the 2014 setup with ceramic clear spray paint and after 3 Chicago winters they look well. Few rust spots from dings during installation. I can take photos if you would like to see. I choose Koni only because of the adjustability.

[BSM n54iS]

Originally Posted by feuer

I have two cars with Koni yellows. One matched with Eibach Sport installed in 2010 with about 75k (still feel better than the 60k Suchs they replaced). Another matched with BMWPS installed in 2014 with about 25k. Regarding reliability of Koni compared to Bilstein I don't have personal experience on any on my cars. At the shop a lot of Bilsteins are getting replaced. Especially the regular black Bilstein. But they are a lot more cars with Bilstein to begin with. So that isn't an accurate comparasment either. Only issue with Koni is rust. I learned that with the 2010 setup. So coated the 2014 setup with ceramic clear spray paint and after 3 Chicago winters they look well. Few rust spots from dings during installation. I can take photos if you would like to see. I choose Koni only because of the adjustability.

Cool thanks.

That's the other thing also, where to put the Koni settings..on the rear for example cuz Turner said in order to get the rears adjusted you have to put them in a press?? I hadn't done the research in diligence on the actual adjustment procedure, I knew about needing to take the rears out, and the fronts being relatively easy. Then some others say the adjustability really isn't too useful to begin with. Yours being an E90 not sure where to set it up for my e92 that's slightly lighter than stock also. Would like to get the rears right on the first go around obviously, and having to 'guess' at what the appropriate valving should be...

[Go Horns!]

Originally Posted by BdSM n54iS

Has anyone here have an actual review 1st hand experience with the swift springs on an e92?? This would help out tremendously

Here you go: http://www.e90post.com/forums/showthread.php?t=899127

[Yozh]

Originally Posted by feuer

Koni yellow matched with BMWPS and satisfied.

I love mine too. Have e93M3 front bar, M3front arms, Monroe upper rears, Turner Al Subframe bushes.

[feuer]

Originally Posted by BdSM n54iS

Cool thanks.

That's the other thing also, where to put the Koni settings..on the rear for example cuz Turner said in order to get the rears adjusted you have to put them in a press?? I hadn't done the research in diligence on the actual adjustment procedure, I knew about needing to take the rears out, and the fronts being relatively easy. Then some others say the adjustability really isn't too useful to begin with. Yours being an E90 not sure where to set it up for my e92 that's slightly lighter than stock also. Would like to get the rears right on the first go around obviously, and having to 'guess' at what the appropriate valving should be...

With adequate tools and know-how removal or rear shock to adjust valve setting is not required. Isn't all that dificult as you think it is. Also, if you don't want to through the the whole ordeal of try and don't like it route you can always post in your local groups to find a guy who's going to let you experience their ride with similar setup to yours. If you like it go with the same adjustment.

[feuer]

Originally Posted by Yozh

I love mine too. Have e93M3 front bar, M3front arms, Monroe upper rears, Turner Al Subframe bushes.

Other than one being I and the other D we have similar setups 😂

[BSM n54iS]

Originally Posted by Go Horns!

Here you go: http://www.e90post.com/forums/showthread.php?t=899127

There's this thread too that I found:

http://www.e90post.com/forums/showthread.php?t=907615

And it's weird a guy in each thread other than the OP ended up not liking the swifts haha

[Go Horns!]

The problem with the Swift Spec-R springs is that the ratio between the front and the rear spring is too biased to the front to achieve a flat-ride. Based on sprung weights of 889F/772R, the stock m-sport springs have a flat-ride at 70 mph. Whereas the Swift Spec-R springs will never achieve a flat-ride at any speed you will ever drive (it is at plus 200 mph).

So if you drive smooth rodes most of the time and you want a firmer ride, you will like the swift springs. But if you deal with bumpy roads, you might end up less than impressed.

I used the spreadsheet that is shared below to do the calculations. I found it here: http://www.eng-tips.com/viewthread.cfm?qid=344263

Hope they dont' mind.

https://drive.google.com/open?id=0B8...Hl2anNYd0dtVUk