[AkisGr]

Originally Posted by cvc 22349a

I've been interested in the KW Street Comfort suspension for a few years but haven't seen many reviews, so I thought I'd post one. I chose the Street Comfort suspension over the V series because of the linear rate springs 286 F/572 R and because I was more interested in ride quality than 'slamming' my car.
My past suspensions have been OE Sport, Koni FSD, Koni Sport and most recently Koni Sport with BMW Performance Suspension springs and bumpstops. In addition to the PS springs and Koni's, I've installed M3 front control arms, the PS front anti roll bar, M3 rear subframe bushings, M3 rear upper links and guide rods, Meyle toe arms and the E91 14mm rear anti roll bar. I was satisfied with the handling of my car but not the ride quality. Every small bump or undulation in the road was transmitted to the chassis and caused the car to move around too much for my liking and to the liking of my favorite passenger.
'DefactoM6' has the KW SC suspension and was very patient in answering the many questions I had. At his recommendation I also had the Ground Control street camber plates installed along with the suspension about 3-4 weeks ago. Last week, I went back to my installer to adjust the ride height and get an alignment. The ride height is approx. 1/4" lower in the front than the BMW PS springs and set at 25.5" from the ground to fender at all four corners. The car could sit a lot lower or could be raised up a little bit. Since the install, I've taken two road trips on Hwy 1, a curvy road on the Ocean with lot's of hairpins, and I've got say I'm very pleased The additional neg camber up front vastly improves grip and reduces understeer. The car is much flatter in turns and just grips! Handling has been dramatically improved as has ride quality. The suspension absorbs most of what was previously transmitted to the chassis. Ride quality is better than oe sport springs with Koni FSD. I don't understand shock valving technology, but I'd say KW does a better job of it than Koni.
The only downside to the KW's is they do make an occasional odd sound when turning the wheel towards lock or going over a speed bump. I think the springs turn or move on the adjustable perch causing a light clunk or grinding sound. I'm guessing this is why HPA includes thrust sheets with their coilover suspensions.
I know there are a lot of options out there; I've been researching suspensions for this chassis for several years. I like that the shocks are valved for the springs and don't need stiffer springs for a car driven on public roads. The suspension may be soft at the track, but it's perfect for spirited driving on public highways!

This is probably one of a couple most helpfull reviews on KW street comfort online.And the fact that you've changed more parts on your suspension makes it the best of all the others.

Well here's the thing. I don't have a Bmw any more(my 2004 330 coupe is long gone).
I have a CLS 320 Cdi (W219) with a Brabus D6III chip and although right now my post seems strange and in the wrong place,you'll see it isn't.

I have the car for 5 years and 107k miles. After many weeks of researching for new suspension(non airmatic),it finally came down to KW SC coilovers. The deciding factors were comfort and slight hight drop with a bit larger wheels (even though i'd prefer 20's,19's is the most probable because i'm afraid 20's will take out to much of the comfort levels).
I got it some days ago but since all suspension parts are a bit tired (107K miles) i thought that maybe i should also change other parts of it so that i improve the feeling of a 107kmiles car,the comfort/smoothness of it and responsiveness.

I've searched online but found nothing on the subject for my car and nobody answered. I'm a member on a couple of Mercedes forums but eventually nobody knew anything(or maybe they just ignored).
And then i stumbled on your post and although its for a BMW,i couldn't help but see the resemblance.
Well,at the end they're both cars with same suspension ordinance.
Both have wishbone links,both have anti roll bars,tie rods,guide rods,strut mounts,joints,bushes, etc, etc. And you seem to know what is good to renew for refreshing the feeling of the ride,or improve it.

I could nowhere find any kind of advise about it and you seem you know a lot about.Any advice ,or suggestion before i install the KW SC would be great!
Thank you

[cvc 22349a]

^ Sorry, I don't. Different cars. These BMW's were engineered around runflat tires which suck. Fortunately for you, the Mercedes was not.
One thought: In addition to the suspension, inspect/replace shock/strut mounts and inspect/replace control arm bushings.

[cvc 22349a]

Update: I sold the Ground Control camber plates as I didn't like the metal on metal bang under hard/full compression for a DD. I replaced them with oem strut mounts and Dinan camber plates and am glad I did as the front end is much quieter. At my ride height with M3 control arms, I can't get under -2d camber up front which is a bit too much for a DD imo. I wish I hadn't installed the Dinan camber plates as I could easily get -1.5d w/o them. Turn in and a reduction in understeer is the same as when I had the GC plates, so I can't recommend the GC plates for a DD. Should've listened to Harold at HPA who stated many years ago he recommended against camber plates for a DD.

[mwahlert]

Interestingly, I just got off the phone with KW and the tech I spoke with said that the spring signature listed for the SC is a progressive spring... but, I'm not sure any more as the installation instructions for the SC and v2 are claiming the same part numbers so maybe he was confused?

he said the SC kit comes with springs 2023/2017 which are progressive springs.

more interestingly, i had a set of these on my 07 back in 08/09, and i swear back then the SC kits had fixed dampening... to this day the product description on the KW website for the SC kit for the e90 makes no mention of adjustable rebound, but includes instructions how to adjust the rebound... i wonder if they changed this at some point... or i'm remembering the past incorrectly.

[cvc 22349a]

Originally Posted by mwahlert

Interestingly, I just got off the phone with KW and the tech I spoke with said that the spring signature listed for the SC is a progressive spring... but, I'm not sure any more as the installation instructions for the SC and v2 are claiming the same part numbers so maybe he was confused?

he said the SC kit comes with springs 2023/2017 which are progressive springs.

more interestingly, i had a set of these on my 07 back in 08/09, and i swear back then the SC kits had fixed dampening... to this day the product description on the KW website for the SC kit for the e90 makes no mention of adjustable rebound, but includes instructions how to adjust the rebound... i wonder if they changed this at some point... or i'm remembering the past incorrectly.

How old are you? I think it's your memory I'm pretty sure they've always had rebound adjustability.
Company sales persons don't always know their products. If you compare SC and V2 springs side by side you'll see the upper coils of the V2 springs taper down in diameter whereas the SC's don't. Due to their shape, ppl will say they are progressive rate springs including my tech.

As a side: I've tired of having a lowered front end for DD and will throw my zsp springs with Koni sports back on when the KW struts are shot. The KW SC struts lose rebound damping force over time but I still have plenty of adjustment left.

[mwahlert]

Originally Posted by cvc 22349a

How old are you? I think it's your memory I'm pretty sure they've always had rebound adjustability.
Company sales persons don't always know their products. If you compare SC and V2 springs side by side you'll see the upper coils of the V2 springs taper down in diameter whereas the SC's don't. Due to their shape, ppl will say they are progressive rate springs including my tech.

As a side: I've tired of having a lowered front end for DD and will throw my zsp springs with Koni sports back on when the KW struts are shot. The KW SC struts lose rebound damping force over time but I still have plenty of adjustment left.

I think I will be going with TCKline Koni SA setup. Probably 300/500 spring rates.

[cvc 22349a]

Originally Posted by mwahlert

I think I will be going with TCKline Koni SA setup. Probably 300/500 spring rates.

For a DD? Those are soft springs. TCK recommends 350/600 I believe.

[cvc 22349a]

I sold this suspension to another forum member because I live in a very hilly town and got so tired of coming to a crawl to make a turn up/down or approach due to the lowered ride height. So, I went back to oem sport springs and Koni sports which was my favorite spring/shock combo and am glad I did. Handling isn't as important as DD functionality/comfort to me. I think I wrote the KW SC suspension was more comfortable than sport springs and Konis? Well that's not true. Also, the chassis is quieter w/o the coilovers. It was a good suspension if I lived where it's flatter and smoother and I was younger.