Which shock?

[Vetruck]

Jesus, Vetruck. My head is spinning. I consider myself a relatively smart guy, but you just made me dizzy with all the info you just dropped!

I drove an all-original, all-stock 1994 C280 on factory bilsteins for 13 years and 250k miles and thought the handling/ride were great! Now, I'm in the C43 and the suspension is pretty worn out but it feels like a "race car" by comparison. I know I hit some interstate on/off ramps a good 15mph faster than I could in my old C280, without even a slight squeel.

I guess it's all perspective. i bought this car for simple prestige- Something a little more classy for the lady and I to go out in to dinner and such so I did not have to lug her around in one of my noisy sports cars. I would not consider a Mercedes a decent handling car at all. I consider them a decent riding car, but not handling- they are engineered for luxury.

The Eibach package and Konis alone should make even a 230 Sport model feel like a station wagon, never the less this crappy little C220 trying to stay on the road in a corner. I have mentioned on here before in another post that I have even tracked a few AMG63's and they are even trerrible in foactory form. most cars sold to the public are set up for the typical old lady driving down the freeway. If the cars were set with better reactive rotation and alignment specs, the typical sunday driver would ass around the rear of the car in a panic situation and hit something sideways or backways. All of the DOT safety standards (airbags, crumple sones, etc) are prety much designed for the occupants to take a frontal impact for the safest crash situation. Thus, they make the car tight in blance from the factory so as not to react to fast steering imputs.

You want a car that handles? you have to tweak these setting and balance the chassis to better balance and geometry.

Just be glad I have not gotten into discussing roll centers, instant center migration,and yawed roll axis. I could teach most of you this for several years and 99% of people never fully grasp the skills it takes to put the proper imaginary image in their head to see it. I am one of those 1 in a million- its partially why I was a NASCAR crew chief on a Supertruck team- I can figure this stuff in my sleep. Don;t ever feel bad not understanding this stuff, most racing teams never fully do.

Dean

[John Jones Jr.]

So I received the Koni Sport (Yellow) adjustables this morning & fitted them. Went for a test drive (20 miles) on various types of roads. There is a massive difference in the cars handling and it's not harsh but well planted. I can take some bends 10mph faster without even trying. The posture of the car is better too, the back is almost level with front now. Delighted so far.

One downside and a bit of a disappointment is that you really can't adjust them on the car contrary to what I thought. The problem is you need to access a very small button on the top of the shock body but once the dust cover/gaiter is fitted you've got no access. So, it's shock out time to change the settings unless I get rubber gaiters that will retract easy enough up over the shock body. For now there're set at position 1 out of the three setting 0-1-2. This could possibly change when I get around to doing the springs.

Springs next.

[kowalski]

do you have an adjustable hat ontop of the shock rod?
like this shock seen in the link
http://www.ebay.de/itm/K392-KONI-Spo...item46027224d2

take some pictures of your shox on your car.
show me that small button.

do you hear more cabin rattle inside your car from these shox?

how is the ride comfort?
did you lose that famous MB ride feel?

[John Jones Jr.]

Sorry, didn't take photos and if I did now all you'd see is a new shock fitted like any others. To show you the button I'd have to remove the shock, see my last post.

No they don't come supplied with the 'hat', they come with a plastic disc (I'll photo that later) which is only fitted when adjusting the shocks.

No issues with cabin noise/rattle and ride comfort is perfect if slightly harder but not crashy - controlled is the best way of explaining it. Actually, the shocks have now shown up another problem, my l/h/s LCA bushes are past their best.

[kowalski]

these shox below for C36/C43 might have a different construction without that misplaced stupeed button?
If you can't axxess that button when the dustcovers are put back in place, what's the point having it there?
What does manual say about this button?

Koni gelb einstellbar 8041-1315SPORT FRONT
Koni gelb einstellbar 8041-1316SPORT REAR

[John Jones Jr.]

The manual (only diagrams, no words) just shows that the button is located at the top of the shock body covered by a plastic disc and a metal cap, remove the cap & disc, press the button, turn the adjuster disc at the very top of the shock and you can then adjust the shock to the next setting. Of course in reality it's not as simple as that even disallowing for the fact the shock gaiter is in the way. Even if the gaiter wasn't fitted this is what you'd have to do.

1. Undo both 17mm lock nuts on top of the shocks.
2. Remove the top rubber mount as that will interfere with the 'feel' for adjustment.
3. Place adjustment disc on top of shock, so you can turn adjustment, that's if you can turn it as there's very little room (see photo)
3. Get somebody else to press the button while you turn the adjustment knob, might be able to do the fronts without assistance but there's no hope on the rears.


Having said all that, I can't see myself adjusting them more than once or twice so it ain't really a big issue, just annoying.

I was out in the car this morning and now I'm thinking I may re-adjust them back to '0' rather than the current setting '1'.

P.s. the photo showing the shocks with the round adjustment knob is a generic photo. I think if you are replacing MacPherson struts there come with the round knob as the struts are located to chassis with an independent top mount.

[kowalski]

how do you know you got no 1 or no 2 settings on front or rear pair?
is there a stop on each step 0 - 1 - 2?

if you have chosen your setting and you're happy with it, there's not necessary to go back and forth with different adjustment settings as you need to remove cover/gaiter everytime?

Did you have to re-use your old plastic dustcovers from your old shox and put them on your new shox?
don't know the exact name for this cover, it's on the top part of the shock, highlighted in black

[Vetruck]

Good morning guys. John, The shocks you have are the 26 series Koni's(the less expensive but better performin and lighter unsprung weight "monotubes"). Koni also makes a twintube sesign which is the 80411 part numbes. Te twintube is the shock with th upper dial knob rather than the removal and depress button mechanism, but as stated, they are more expensive, heavier, and overall a slightly inferior performance design. Knoi makes that series simply for the person that wants ease of adjustment.

I have the Monotubes coming-Just like what you have. The twintubes are more suited for the weekend lazy person that wants to autox his car, but then drive it to work all week so the dial is good for the average joe that does not want top perfromance and mainly does not want to get his hands dirty. The monotube will givve you better valving performance since it is a high pressure single large valve disc design. The Koni twintube is unique over other brands conventional twintube styles as that Koni uses separate valve disks (yes two separate places- one for rebound, and one for compression0 where everyone else uses on small one that tried to handle both vavle passages. The twin tube desgin has an internal tube that is very small in diameter so you can not have adequate vlave ports for both on that small disk- but other brands do it anyways. This causes alot of pressure on the fuild so it heats up more and foams very easy. What Koni did is made the shaft disk the rebound disk(with a vertical inner adjustment rod to the top of the shaft- hence the white dial), and then they put the other compression valve disk at the base of the shock where the shock oil exits the inner tube and enters the outer tube. This design is heavier because of two tubes and two disks and the thicker innerrod and outer shaft, It also only allows for a low pressure nitrogen charge so it does foam still on very agressive raod course use.

The monotube has a large open oil capacity and a very large single "dual porting" disc that is adjusted by turning depressing the button and turning the shaft which spins the disc internal more open or closed on the rebound passages. Its a a better design that allows the use of an absorbtion HP nitrogen porton inside the bottom of the oil chamber to keep the oil under pressure so as not the foam- the HP nitrogen also acts as a damper internally to help take away fast movement harshness- in a sense it acts like the more asdvance 4-way shocks a little bit (but just a little- this is more advanced to explain and not viable for us so I will spare the details)

You have the better Koni shock on there, the 26 series

[kowalski]

Good morning guys. John, The shocks you have are the 26 series Koni's(the less expensive but better performin and lighter unsprung weight "monotubes"). Koni also makes a twintube sesign which is the 80411 part numbes. Te twintube is the shock with th upper dial knob rather than the removal and depress button mechanism, but as stated, they are more expensive, heavier, and overall a slightly inferior performance design. Knoi makes that series simply for the person that wants ease of adjustment.

I have the Monotubes coming-Just like what you have. The twintubes are more suited for the weekend lazy person that wants to autox his car, but then drive it to work all week so the dial is good for the average joe that does not want top perfromance and mainly does not want to get his hands dirty. The monotube will givve you better valving performance since it is a high pressure single large valve disc design. The Koni twintube is unique over other brands conventional twintube styles as that Koni uses separate valve disks (yes two separate places- one for rebound, and one for compression0 where everyone else uses on small one that tried to handle both vavle passages. The twin tube desgin has an internal tube that is very small in diameter so you can not have adequate vlave ports for both on that small disk- but other brands do it anyways. This causes alot of pressure on the fuild so it heats up more and foams very easy. What Koni did is made the shaft disk the rebound disk(with a vertical inner adjustment rod to the top of the shaft- hence the white dial), and then they put the other compression valve disk at the base of the shock where the shock oil exits the inner tube and enters the outer tube. This design is heavier because of two tubes and two disks and the thicker innerrod and outer shaft, It also only allows for a low pressure nitrogen charge so it does foam still on very agressive raod course use.

The monotube has a large open oil capacity and a very large single "dual porting" disc that is adjusted by turning depressing the button and turning the shaft which spins the disc internal more open or closed on the rebound passages. Its a a better design that allows the use of an absorbtion HP nitrogen porton inside the bottom of the oil chamber to keep the oil under pressure so as not the foam- the HP nitrogen also acts as a damper internally to help take away fast movement harshness- in a sense it acts like the more asdvance 4-way shocks a little bit (but just a little- this is more advanced to explain and not viable for us so I will spare the details)

You have the better Koni shock on there, the 26 series

are these inferior
these are the only for C43.
8041-1315SPORT FRONT
8041-1316SPORT REAR

[Vetruck]

how do you know you got no 1 or no 2 settings on front or rear pair?
is there a stop on each step 0 - 1 - 2?

if you have chosen your setting and you're happy with it, there's not necessary to go back and forth with different adjustment settings as you need to remove cover/gaiter everytime?

Did you have to re-use your old plastic dustcovers from your old shox and put them on your new shox?
don't know the exact name for this cover, it's on the top part of the shock, highlighted in black

Koni 26 series have a very noticible click each time the rebound adjuster moves. Koni's settings are 0-3. THose settings have individual clicks that the button will pop back out each time for each of the 4 setings. (don;t ask me why Koni uses "0" as one of the four settings but that's what they start with. 0, 1, 2, & 3- 3 being firmest of the rebound setting.

You need to remove the shock for adjustment, not just remove the dust cover- so the use of rubber boots is unnecessary. You have to push downthe button firmly and spin the shaft inside the body to the left or right to the next click. The button will pop back up at the next setting so if you need to go further you then have to push the button again each time- it only allows you to move the adjuster once click each time you press the button. What the button is doing is holding the outer disk in position as you turn the shaft which connects to the inner disk. It is alot like the buttons you press on a skill saw to hold the blade from rotating as you wrench the center nut off. Other wise the nut pins with the blade when you try and turn it. The Koni buttom holds the disc like the saw button holds the blade.

A little tip is you can make machined bottom pins with clips to hold the base of the shocks in place for quick release insteadof bolting them in place. We do this on the racecars very commonly. I had these on my NASCAR Supertruck so when I needed to pull an entire coilover for a spring or damper change I could do it rapidly. there can not be slop in the pin though or you will hear them all rattle and knock on every bump. Youc an bolt on the top eyebolt and never have to take that off, just undo the bottom shock mount.- however, that's me because I remove the black plastic dust cover boot so I can press the buttom without removing the top mount and having to pull that crappy thing out of the way. Koni uses that to help keep forgein debris of the shcok body top and the seal. I live in sunny Southern California where we do not get snow conditions and thus salted roads- this is very corrosive so they make those protective boots for situations like this- its a worse case senerio thing to hve those boot covers on there. Here is my old Camaro I ran 15 years without covers on them

[Vetruck]

are these inferior
8041-1315SPORT FRONT
8041-1316SPORT REAR

On a scale of 1-10, 10 being best- those are an 8 whereas the Koni 26 series are a 10 in performance level. Most twintube designs I discribed are a 3-5 on that scale. Koni makes a far superior twintube, but it still in not a good as a monotube

[Vetruck]

The Koni Monotubes for our cars are part #'s
26-1575sport
26-1576sport

[John Jones Jr.]

Vetruck, indeed they are 26 Series Koni's . I wanted monotube shocks regardless of the brand due to being so impressed by the Bilstein B6's I fitted to the 190E 2.5-16 many years ago. So, I'm not overally upset that I have to remove the Koni's to adjust them. Thanks for your input in the above post and also thanks again for your earlier advise and endorsement of these Koni's.

One thing Vetruck, the car is driving so well with the standard Merc Sport springs I'm wondering how much difference a set Eibach springs will make? Any views?

[Vetruck]

You are welcome- I mentioned to the forum I am a suspension guru- you guys are starting to reap the benefits on having me around here. Just wait until I learn this car more and more the more I tinker with it over the years

I would probably not suggest you go to the Eibach setup with the Konis because Koni has a more agressive compression valving that Bilstien does. That makes up for dyanmic spring rate in compression movement of the shock, but not dynamic "set" of the shock. Once the spring has compressed in steady state of the corner, the shock damper force goes away when it is under "dynamic- static" load so thus it is only the spring rate holding the roll of the car at that point.

But as for straightline ride comfort, it will limit the travel of a softer spring so as not to bottom out a wheel travel like a lsesor valved shock will do like Bilstein. It is all in feel. The Eibachs will definately make it ride harder with the Koni's as opposed to the Bilsteins, but the Bilsteins also do not have the agressive rebound settings that make the koni shine in cornering chaiss weight control. Koni's are geared to be used out of the box with lower spring rates than Bilsteins


Why I am telling you this is because I see you already stated you want to back the Koni Rebound settings back to "0". If you think the ride is too hard right now then you will not like the Eibachs

[John Jones Jr.]

It's not that I think the ride is too hard, as per my other posts I'm driving a different car since fitting the Koni's. I'm just looking for a good compromise (the impossible!) thus, I was thinking of resetting to '0' and leaving the springs standard. And as I'm on a budget the 200 bucks for springs would go a long way towards other bits. What am concerned about is, if I keep the Merc Sport springs will the car be undersprung for new shocks? Hope that makes sense.

[Vetruck]

No is not under sprung. The rebound setting holds the shock from extending, thus it controls two things
1) body pitch & roll. The chassis weight of a car braking and/or going into a corner will roll over the fronts (braking) on onto the outside wheel (cornering) what rebound does is holds the rear shock from extending under braking, and holds the inside shocks from extending as the body roll away from them extending them. Rebound helps cornering.

What happens if you go too high with the rebound settings is a) you can start to left too much pressure off the rear tires and cuase them to skid, and b) you can have too much force as to not allow the wheel to return to the ground and thus "jack down" the spring if it is too soft for the setting and not returning the wheel to the ground fast enough {this last part is also "2)" }

More on 2) the more the spring jacks down, the more efective rate height the coils are and thus rate increase when slightly more compressed. It will feel like a stiffer spring rate and thus the tires will start having to take the blunt of the force in bumps making the sidewalls compress more rather than the suspension doing its part. The tires taking more percentage of the load will now cause a bobble and make the car wander a little. It gets worse as the rebound setting goes up. The higher static rate of a spring, the less likely for "jacking down" obviously.

[Vetruck]

Now that you have read all of this, your head will start to hurt a little. Lets simplify it. you know understand what Rebound does, so just simpley use tht understanding of hat happens when too much and too little force is exerted with high or low settings and go dil it to where you feel its a comfortable ride. You'll know when the rebound is too high, you will feel it hit harder on consecutive bumps.

lastly, if the car is too loose, lower the rebound one click and/or raise the front one click- if the car is tight then raise the rear one click and/or lower the rear one click. The rear ride quality is important. that is what "bucks you in the ass" it its too harsh, or will casue excessive body movement if too soft. You knidof have to play with both front and rear settings together until you get a feel of how it all works. You will NEVER need to go to #3 click on any of them unless you are on a racetrack. then the front "may" go to 3, but certain the rears never will. It would all depend on how smooth the track surface is and how much lateral grip you are getting(and thus body roll) under tight hard braking corners like autox. Road rae courses will probably only still see 2 front and 2rear/ or 2 front 1 rear at my guess once the tires are hot. When the tires are could the 2 front and 1 rear would make the car tight until you get the rubber warm.

[Vetruck]

I gotta go- I can answer more later if needed.

[John Jones Jr.]

No is not under sprung.

[kowalski]

twintube Koni's are they more problematic?
are they prone to leak more often?
do they have less long life performance and wearing out faster than monotubes?

now I'm getting really confused if I should go for twintubes for my c43?!
mono's seem to be more PITA to adjust if I have to remove them from the car and then adjust the firmness and then put them back on?
Ouch!

[Vetruck]

twintube Koni's are they more problematic?
are they prone to leak more often?
do they have less long life performance and wearing out faster than monotubes?

now I'm getting really confused if I should go for twintubes for my c43?!
mono's seem to be more PITA to adjust if I have to remove them from the car and then adjust the firmness and then put them back on?
Ouch!

No, they are more expensive and a little heavier, and the potential to foam if used really really hard becasue they are low pressure nitrogen gas charged rather than high pressure nitrogen charged like the monotubes. The Twintubes run about 5bar of pressure whereas the montubes run about 20bar of pressure. If you are noeve rreally driving competitve on hot days for 20 minutes straight all-out on a demanding road course then you will never fade the twin tubes. The twin tube design is merely for ease of adjustment. They cost a little more, but are actually slightly inferior to the Monotubes as I have already explained why. The 26-1575sport will fit your C43 fine- it is the same exact mount confirguration. From what I have always seen, the 8041 series "should have" the top dial adjuster, but do not quote me on that since I have never seen the W202 version. Any other Koni twintube 8041 I have seen in Chevy applications always have had the top dial setup. The monotubes always have the button adjustments.

I am big on having lighter weight suspension parts. Moving suspension parts is "unsprung weight" Chassis weight is anything resting on the springs or basically "Sprung weight. The higher the ratio you can get with spung to unsprung weight the BETTER your car will both ride AND handle...period.

[kowalski]

hey buddy
i checked with koni's website, there's only one shock recomended to my car and it's the 8041 versions, it doesn't say anything about 26 series.
8041 is easier for adjustment the other one needs more work.
for average performance driving on motorways i believe 8041 will do fine, won't you say yes to that?

if buying monotubes, what is the best adjustment for them from the first time and not having to pull them out again?
doing a 2 front 1 rear - 2 front 2 rear - 1 front - 2 rear - 1 front 1 rear?
it will cost money at the shop and take time to pull everything out again to do other test-settings

[John Jones Jr.]

Kowalski, if you get the 26 Series Koni'e set them at '0' first off. Of course it will depend on the springs you have and what your preferences are. But from what you've be saying you might be best off getting 8041's unless as Vetruck has mentioned you are going to do some type of heavy track work.

[Vetruck]

hey buddy
i checked with koni's website, there's only one shock recomended to my car and it's the 8041 versions, it doesn't say anything about 26 series.
8041 is easier for adjustment the other one needs more work.
for average performance driving on motorways i believe 8041 will do fine, won't you say yes to that?

if buying monotubes, what is the best adjustment for them from the first time and not having to pull them out again?
doing a 2 front 1 rear - 2 front 2 rear - 1 front - 2 rear - 1 front 1 rear?
it will cost money at the shop and take time to pull everything out again to do other test-settings

TO give you an accurate answer right now would be silly of me in light of that fact that mune should be here on Monday. I will stick mine on with 1 front/1 rear onlly because of my personal experience with Koni's I have never run any set with them just on 0 front or rear on any other car= HOWEVER, this is the first luxury car I am putting them on. I am stickong them on the car tright now with the car completely stock and with the stock 15" wheels and tires. The tires I have onit right now are Michelin Primacy with about 20% wear. they are a very comfortable and quite riding tire but still are poor in handling characteristics being a passenger tire. With that said, I am predcting that I will probably like a 2/2 on them until I puit the 18" wheels and tires on tthe car which yeild a firmer ride. At that point it will probably be a 1/2 but these are merely experienced "guesses". I can give you a "first hand experienced answer" in a week if you have time to wait. Once I get the springs up front and the larger rear bat then it will hopefully drop to 1/1 when the car rotates better and has less roll to control

The 8041 is still a great shock- far better than most anything else out there so you can not go wrong buying either. Compared to stock being a 1, the 8041 is a 9 and the 26 is a 10 on a scale of 1-10. I would take the twintube Koni over the Bilstein HD any day of the week- and you can quote me on that. Bilstein is diehard monotube design-whu? because Bilstein invented the monotube shock 40 years ago. They frown on the conventional twin tube design- bu the Koni twintube is not a typical "conventional twin tube design, I explained how Koni developed a separate two disk gas pressure design- they kept developing the twintube unlike Bilstein and actually still do use some twin tube shocks offered in their racing catalogs- albeit they are lightweight and heat bleeding aluminum shocks and are very very pricey, but they ARE in fact just like the 8041 line- but are labeled 8212 series for the aluminum buld and double adjustment knobs (one at the base that also adjusts the lower mounted compression valve disk at the base of the internal twin tube. They are just not steel bodied over the counter units like the 8041sport yellows but are basically the exact same design internally but with heavier parts than the high end racing versions.

Koni from what I know has continued the development of the twintube (whereas Bilstein dropped any interest in them years ago) becasue of the ease of single and double adjustment abilities where class restrictions allow for adjustable shocks. It makes for much quicker "pitstop adjustments" and thus why Koni has the reputation in auto racing. Recent designs like from Penske in the developent of very high priced 4-way shocks again revolutionized the industry, but most people had no idea how to set them and were lost just messing with adjustments. Lastly, Bilstein never developed the shock becasue when they designed the monotube yearrs ago it became their legacy as well as their sales pitch frowning on the conventional twintube shock- but the conventional twintube is terrible compared to Koni's gas charged two disc twintube

[kowalski]

Thanks for your input.

I spoke to my mechanic today about the monotube vs twintube.
He told me to stick with Koni twintubes as they will be much easier to adjust the settings.
I will probably buy them soon or next month.

I hope these Koni's will give me a pleasent ride matched with Vogtland springs.
I drove my car on the freeway today up to 130mph and I don't like my stock factory suspension.
It feels like my car is moving sideways, like a snake crawling in the sand.
This is how it feels at high speed.

I have replaced all bushings and LCA/UCA on front axle.
Now it's time for new replacement parts like bushings and suspension arms for rear axle.
I've already bought these stuff and I will replace them when I change my shox and springs.

2 years ago I bought new Continental SportContact3 aftermarket tires, they don't have the MO stamp which means Mercedes Original.
Would there be any difference between MO stamped Conti's and aftermarket Conti's?
Something like instability problems, or they might be more tramline sensitive?
Dimension is 225/40/18 front and 255/35/18 rear

I have installed MB Arts adjustable camber arms and did a 4 wheel align when I got my new tires.
This shop also sells rear toe links.
Are these necessary to have when using adjustable camber arms, getting a perfect synergy match?

Adjustable rear toe links do they give more precise straight line performance driving @ high speed or is it only noticeable from stand still launches?