lap

those that have "played around" with your settings, what have you finally "settled" on.

Would you be kind enough to enlighten us on:

1) TYPE (Bilstein/ Carlson/ H&R, etc..)
2) F/R Height (Collar postion, etc.)
3) F/R Absorber Setting (1-9, etc. if applicable)
4) YOUR RATING / Comparison to STOCK of the mod (1 = little real improvement TO 10 = bring me to the track!!!)

THANKS.

Got my PSS-9's just in (Sorry HARRIS, would have gone with you, but did a package deal in Europe for a few of my other cars as well ... BUT will probably do the CF mod when i get back into the black.. ) and am looking for some HELP

TIA
lap

smgC32

You will find all this in recent threads this month.

gamedna

Ask Harris, he knows everythng......

Prasith32

lap,

check out some of these threads.


Great writeup by smg on the carlsson. I gave this to my dealer when I asked them to put those in for me and they said it was very informative and helped them a lot. No pics but like smg said who needs pictures when he has over a thousand words

http://p066.ezboard.com/fmercedesc32...cID=1263.topic

some stuff on ride height

https://mbworld.org/forums/showthrea...threadid=72476

some miscellaneous stuff

https://mbworld.org/forums/showthrea...threadid=73335


hope that helps and please post your impressions on how it handles.

Prasith

AMG BRED

sarcasm?

gamedna

nope~
Since Harris had tried them all, thats why I think he supports to know it .....

lap

I have been following the Suspension threads for almost 2+ years now and I would like to thank Prasith32, Harris, SMG etal. for your links/comments.

The reason that I started this separate thread was to get a "simple and concise" commentary on what people may have started/finished with in one neat consolodated thread.

I will post my impressions after installations.

TIA


PS. Where can I locate a PSS9 "HEIGHT ADJUSTMENT TOOL" both of my kits did not come with one

s4iscool

those *******s never include the spanners...alwasy make you go out of your way to get them. HR packs them in all coilover packages.

Harris

For those who know me well enough, you know I no longer like to discuss the PSS-9 in public. Just let the product speaks for itself.

"lap": if you want any further input from me, you are more than welcome to send me an e-mail (although I am not too happy that you didnt get the suspension from me! Hahaha. j/k)

The adjustment tool should be hiding somewhere inside the box. Usually at the very bottom of the box or tug under one of the flaps.

smgC32

The Carlsson packaging is immaculate. In any coilover kit, you need two wrenches as the adjustable collars are of a different OD. Carlsson has them wrapped in foam sheets nestled securely within on of the springs. Call Bilstein NA and they will sell you a set through their customer service department. You can adjust the suspension without them by using a screw driver and a hammer. It is much easier and better to set your ride height prior to installing on the car. The PSS-9 instructions should give a suggested ride height like the Carlsson's do.

Prasith32

lap, (and anybody else that's interested)

I summarized all the threads that I found pertaining to carlsson install for my dealer. I am having the dealer install it and they have never done the carlsson or pss9 before so I put this together for them. It is basically just taking everything that smgc32 said and making it into a pretty format and putting my numbers in it. Just a disclaimer none of this is actually mine I just gathered the information.

-----------------------------------------
Writeup on Carlsson RS Coilovers By a Knowledgeable C32 Owner
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Introduction and About the Kit
------------------------------

Well, they finally arrived after a much anticipated wait. I will be installing them hopefully by the weekend. Here are my observations of the kit:

The quality of construction is top notch. Beautifully designed and put together including near perfect welds. This kit is manufacturer by Bilstein using their PSS-9 design and technology. What seperates the two is the proprietary valving and springs. In addition to the Bilstein markings and labeling on the units, Carlsson also has their logo and part numbers engraved on the finely polished aluminum strut housing and rear shock assemblies. The nine-way adjustment knobs are identical to the PSS-9. Besides the unique markings, the color of the rear shock tubes and springs are what seperates the two visually. Carlsson uses black on their rear shock body, while Bilstein uses yellow. Carlsson springs are a dark blue/purple color, while Bilstein uses their standard powder blue color.

The installation manual is actually quite good considering it foreign produced. The rear adjustable spring perches are very nice units and will secure well to the lower frame assembly. The front springs have a unique plastic tube that surrounds approximately 1.5 coils and starts near the top of the spring. I am assuming that this piece will function to reduce vibration and noise from any coil bind that occurs at this section of the spring which is right next to the upper strut bearing. The rear springs come with their own upper spring "cap". The kit comes with some single use lock nuts to be used during the installation.


Things Needed from MB
---------------------

1) You will also want to go out and buy replacement factory bolts and nuts as instructed so as not to reuse some of these "old" pieces as they have "stretched" are are not for re-use. You will need 8 nuts (2 large, 2 medium, and 4 small size) and 4 bolts. I discarded the part numbers but they are easy to identify in the Carlsson installation manual and the MB parts department computer files. These pieces must be replaced in order to maintain the safety of the vehicle.

2) At the same time of installation, you should also install the factory camber correction bolts to dial in the appropriate camber setting you wish as well as equaling out both sides of the front suspension's camber readings.


Ride Height Measurements and Settings
-------------------------------------

I will be setting the ride height and valving to start as follows:
Measurements are in inches from center of wheel (use the MB star), to the top of wheel arch.
BTW Rear stock height is variable on many cars and depends on which spring pad MB has on yours. It is best to first take measurements based on the pad you are running. I think there are 4 different types and I prefer to use the thinnest one. I would recommend doing a stock measurement and recording the values and that way you can make sure you are getting the right lowering on the rear.

My stock measurements are

Front: Stock = Left 15" Right 15" (there is usually a variance on this from the factory)
Rear: Stock = Left 13.625" Right 13.5" (there is usually a variance on this from the factory)


The Carlsson is to be set at
Front - Left 13.50" Right 13.50" (a 1.50" drop) which should be about half way between the approximate 1" adjustment range of the strut's useable threaded section. Valving to be set at "8" (please refer to the valving section later).

Rear - Left 13.00" Right 13.00" (a .50" drop) which should be about two thirds down from the 1.75" useable adjustment range upon the rear threaded collar. Valving to be set at "8" (please refer to the valving section later).


Settings for the Coilover Adjustable Collar
-------------------------------------------

NOTE TO PAUL: The following settings were written for a ride height of 13.0" on the front and 12.5" on the rear. I would actually like the settings to be 13.50" on the front and 13.00" on the rear so please revise the numbers presented below accordingly. Thanks.


In any coilover kit, you need two wrenches as the adjustable collars are of a different OD. Carlsson has them wrapped in foam sheets nestled securely within on of the springs. It is much easier and better to set your ride height prior to installing on the car.

Front Strut/Spring:
I set the adjustable lock collar at .375” from bottom of strut threads to underside of collar. This height puts the top of the upper collar/spring perch at just about the top of the tire. The car sits at about 13.0” from fender lip to center of hub, or 2.0” lower than stock. It appears that the range of adjustment is about 12.625” at the lowest setting to about 14.125” at the highest setting. So from stock ride height of about 15”, the Carlsson kit allows an adjustable range of approximately .875” – 2.375”, or about 1.5” of adjustment. The installation instructions indicate to set the collar height at 215mm (8.5”) from the center of the middle spindle-mounting hole to the top of the upper collar/spring perch. This would force the collar to be set at maximum ride height of about 14.125”. This could be where Carlsson wants the front ride height to be, but I felt it was too high and I started at a much lower number. Once the car is corner balanced, we will see where the car wants to sit front and rear. There is approximately a tight four fingers width between the tire and fender lip with 4/32” tread left on the front tires.

Rear Spring:
I set the top of the upper collar/spring perch at about .875” down from the top of the threaded stock. We originally set this height at 1.75” from the bottom of the threaded stock to the top of the upper collar/spring perch and then adjusted it down some to set the desired ride height of 12.5” from the fender lip to center of hub, or 1.0” lower that stock. The Carlsson installation instructions indicate to set the collar height to 52mm (2”) from the bottom of the threads to the top of the upper collar/spring perch. It appears that you can adjust the ride height from about 13.375” at its highest, to about 11.875” at its lowest setting, or about a 1.5” adjustable range. 12.5” is just about in the middle and approximately 1.125” from the bottom of the threads to the top of the upper collar/spring perch. Any lower in the rear would be problematic in adjusting the ride height in the future due to the upper collar hiding within the lower control arm recess and being inaccessible to the supplied wrenches. There is approximately a tight four fingers width between the tire and the fender lip with 1/32” tread left on the rear tires.

I have effectively lowered the car 2.0” inches in the front and 1.0” in the rear for a 1.0” differential between the front to rear rake. In stock ride height there was a 1.5” rake differential (15.0” front, 13.5” rear).

The current body clearance dimensions are:

Center of front bumper = 5.4375"
Corner of front bumper at side edge = 4.50"
Rocker panel at front edge = 4.4375"
Rocker panel at front door seam = 6.375"
Rocker panel at rear edge = 5.375"

I did not take pre-installation reading of the same section heights. Maybe someone else can for comparision.

Prasith32

CONTINUED






Some Miscellaneous Information about Parts in the Kit
-----------------------------------------------------

The two nuts and metal raised washer provided with the kit were not used. Neither lock nut fit on any of the components or factory bolts, and the raised metal washer fit nowhere as well. These items are not identified on the installation instructions. The plastic tie wrap that was included is used to secure the ABS line assembly plate to the lower strut. I will have to find out where these pieces go out of curiosity.

Installation is about a 3-hour job with the right working tools. Expect to be billed 4-6 hours by an independent or more from the dealer if they are willing to do the install.

So far in the few miles I have driven today, there are no rubbing issues front or rear, either in lock to lock turns, driveway/road bump clearance, or fender clearance.


Information on Setting the Adjustable Dampening/Valving
-------------------------------------------------------

I have set the strut/shock valving to the number 5 position for now, which is right in the middle of the 9 settings. Just like the Bilstein PSS-9 system, 1 is firmest, and 9 is softest. The adjustable monotube design typically will adjust rebound values 2.5 times that of compression values. Typically this system will have a 20-point spread for compression, and a 50-point spread for rebound. I did not have an opportunity to dyno the shocks and test the spring rates since my connection no longer does this type of work. What makes the RS/PSS-9 different from the Koni, KW, etc. rebound only adjustable units is that rebound and compression change together in a linear but factored way. For illustrative purposes the following rates are probably close within 15%: Front Rebound: 200 – 250, Front Compression: 60 – 80, Rear Rebound: 130 – 180, Rear Compression: 100 –120. If we look at the front values we can see that for every 5 points in compression, we get 12.5 points in rebound, or 2.5 times compression. In other words, for the front valving when you are at R=200, then C=60; R=212.50, C=65; R= 225, C=70; R=237.50, C=75; R=250, C=80. To simplify the formula I used 5 steps rather than 9 (increments of 5.5 for rebound, 2.22 for compression). Within reason we could assign these values to setting numbers 1,3,5,7,and 9 on the valving adjustment knob, 9 being 200/60, and 1 being 250/80. The same formula holds true for the rear shocks. Again these are educated guesses as to the exact rebound/compression values but provide a framework of understanding as to how the shock works. In a twin tube design, such as a Koni, with only rebound adjustability, we could illustrate with the same valving values as above that if the compression stayed the same, lets pick the middle value of 70 for arguments sake, the rebound would adjust 50 points or even more, so we would end up with maybe R=180, C=70, R=200, C=70, R=220, C=70, R=240, C=70. This is not a worse design, just different in the nature of the shock design. Double adjustable twin tube designs allow both adjustment of rebound and compression separate from each other. You will fine-tune the shock with the rebound, but you will also find that you use a higher compression number as you increase your rebound numbers and/or spring rates. The Bilstein adjustable monotube design adjusts both for you and takes the guesswork out of the double adjustable units, although not ideal in its nature. Double adjustables are always better because you can tune both rebound and compression independently without being locked in to a particular combination. The problem is most people don’t have the patience or understanding to commit to properly setting up their car’s suspension.

A benefit of a monotube design is that they hold up better and dissipate heat more efficiently than twin tube designs, which will foam more easily when pushed to their limits, unless you move up to remote reservoir units. Additionally, the RS/PSS-9 strut is a Group N type upside down piston design, which has an internal bump stop, and an inherent shorter shaft for increased travel at reduced ride heights. The strut reacts quicker and helps to reduce unsprung weight. The other factor in shock tuning is the difference between low speed and high speed valving values. It is the low speed values that affect comfort when driving in normal traffic around town. We will have to see how well the RS is tuned within these frequencies.


Factory Camber Bolts Install and Alignment Details
--------------------------------------------------

I installed the factory camber bolts but was only able to get -.87 and -.89 in the front. Something may be wrong with the install. I will have to go back and check again. I should get at least -1.25 according to other users if not -1.5. However as the car is not adjustable in stock form and the acceptable stock alignment variance is between -.04 and -.64, this is all that I may be able to get on my particular car. If I started at -.04 (I did not take a pre-coilover install reading) and ended up at -.89, then I had -.85 degrees of adjustment. If others started at -.64 and added -.85 degrees of additional negative camber with the camber correction bolts, they would end up at -.1.49. This makes logical sense and may account for the differences. Either way, someone needs to make an adjustable camber plate for this car providing up to 3 degrees negative and retrofit the 4matic strut tower configuration to our cars.

As I mentioned before the front camber is -.86 and -.89. The rear camber is -1.45 and -1.76 which should be more than enough around town and acceptable in the canyons. I will take some tire temps next time out during our next photo shoot. At stock rear camber, the inside block was wearing out faster than the outside with 265's. It will only be worse now and will require a dismount and side to side rotation to extend the tires life. New Toyo T1-S's will be here on Monday, and just in time since the steel cords on the GSD3's are slowing me down BTW, the GSD3's are out of stock in the country for another month and the 265's need to come from Germany, so I went with the Toyo's. Nero's are also out of stock on the West coast. No problem getting Pilot Sports though. The Toyo's average selling price for 235/265 is 215.00/240.00. I am looking forward to testing these tires with this setup. I have been a big fan of the RA-1 over the years.

The bump and rebound valving values are significantly stiffer than stock. It is very difficult to push the front end down without flexing the sheet metal. The rear requires twice the effort to compress than on stock. Almost no side to side motion when the car is rocked. The current lowered stance looks very aggressive at 13.0" front and 12.5" rear. The rear could go another .25" lower and look right but I don't think it is necessary. The front does not need to go any lower. In fact, it may be better to raise it up by .25". We will see when we corner balance the car. The front and rear looks visually balanced with the same gap at each wheel wheel, about a fingers width. The car looks low and noticebly so, even when only looking at the roof line. The driving position feels better as well, as the car sits at a more forward angle. Before changing the shock valving settings, I will push the car in various conditions to evaluate its middle position baseline performance. Already, body lean has been almost eliminated at least around fast corners in town. We will see in the canyons and the track. Speed bumps are absorbed easily and quickly with no "after-bounce" like with the stock set up. Freeway transition strips are taken in stride and do not upset the chassis. I tried all the problem areas in town for clearance problems that I find on my E36 and the C32 clears them all. Lock to lock is OK, as is all driveways. No rubbing on inner fender or at lip. I took a few speed bumps at 30mph just to see what would happen with no problem and no bump stop intervention. The concern with lowering the car too much in the front is bottoming out the strut. Fortunately, with the upside down design of the Carlsson/Bilstein strut, travel has not been a problem.



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Once again thanks to smgc32 and all the others from the suspension threads on the c32life forum for being so prolific and technical.

Hope it helps.

Prasith

smgC32

Do I get a consultant fee for this?! I started the thread on C32life and will continue to post within that thread for consistancy in the future. To be fair and loyal to the other forum, a link would have sufficed.

Prasith32

smg,

just think of me as your editor

If you notice I actually combined a few different tidbits from quite a few threads.

if you do start writing technical car novels i would be glad to edit for free.

sorry about posting on this thread.

I had to put this together for my dealer anyways so I thought I would post it here.

Prasith

lap

I've looked through all the material supplied and cannot determine what "non-re usable" mercedes parts I should aquire. Are these the bolts on the "top" of the suspension towers?

Any further help / Part #'s would be greatly appreciated

Hopefully can get this done by month's end!!!

Thanks again.
lap

smgC32

There are several bolts and nuts that should not be reused, although most shops reuse them, especially the independents. These are the bolts and nuts that hold the strut unit on. The Carlsson Instructions indicate which bolts to replace. Some of these bolts and nuts stretch during torqueing and were meant to be single use.