Spring and spring pad types- Pre '96 vs post '96

[Vetruck]

I took a look a my car today underneath ('94 C220) and can not see the spring pad up inside the upper can enough to see any identification bumps. However, reaching down through the center of the can with my finger, the rubber spring pads in there do not see more than about 1/2" thick both front and rear Assuming that the spring coil recesses into it a little, I must have the 8mm units on there.

When I do an internet search and "add up the points my car options have for weight" my catagory falls into the 47-52 lb which is the thinnest 201 321 09 84 (8mm pre '96 pad #1). I was curious after all the research I have read on these cars over the last few months as to how much adjustability I have with my current stock setup in going thicker or thinner and as to what options I have availiable based on this thread that shows spring pad part #'s and thicknesses. http://mbworld.org/forums/c36-amg-c43-amg-w202/416269-suspension-spring-pads-shims-c43.html

Now the real question-
does anyone know if the later spring pads (post '96 210 series pads) fit into the Pre '96 spring cans? Now I know the springs are different shape on top. The early ones like I have are tapered top ends and helox bottoms standard indexing, but will the later year helix top srpings and spring pads fit into my car if I change them all out to later year stuff?

Reason I am asking is becasue I am looking at some '96 and later Eibach prokit front springs that are made for the heavier C280. Eibach does not make a Prokit for the 94-95 C280, nor the c220. So what I am looking to do is change the front spring pad to the later style and use the later helix top springs with the C43 #1 5mm pads.

Will this fit my car? or did Mercedes change the can and spring diameters on the 96 and later W202's?

[Vetruck]

Probably my other option is to try a 94 C280 stock spring and just slightly trim a little off the bottom of it. That C280 spring in my C220 would give a little front rate increase I am looking for, then I will worry about balancing the rear of the car to get it to rotate with swaybar size and shock adjustment (I have some Koni Yellow Monotubes on the way)

[Vetruck]

I see this forum really lacks knowledge on these cars other that headlight/tailight replacement,,,oh well. I guess I have to do all the research myself.

[Vetruck]

Im just looking to see if the later year cars run the same 4" top can on the front and rear speings. I know the bottoms are the same via the same use of front and rear lower control arms, so the bottom spring diameter and index are the same- but is the top the same diameter. Someone please don;t make me take a trip to the junkyard just to measure a later year spring cup

[anf6789]

I know they are different pads but I'm not sure if they are interchangeable or not. I can't see why they wouldn't be.

[anf6789]

As long as I've owned my 202s I've never lowered one....

[Vetruck]

I am have pretty much concluded what direction I am going. Since I havee the lightest weight car option out there off all w202's it makes thngs real easy for me to modify it using OEM springs. I am just going to get the heavier rate c280 springs and trim them to height for the front. I am leaving the rear stock springs and trimming them slightly to height (only need about a half coil off them). The rate will slightly go up, but not much, and I get my ride height. I have it dampered very well with the Koni's so it will stay softly sprung in the rear as opposed to the front (this makes for a great ride quality) and I will loosen the rear so the car will rotate with just a larger rear aftermarket H&R swaybar and higher rebound dampering- I'll leave the stock front swaybar alone. This should give me a great ride qualitty as well as a much better handling car that will not stand on its nose every tme I brake and corner.

[anf6789]

Cutting Coils?! OH MY.. just kidding, theres always that age old debate. You know what you are doing though...

How come you got away from the Weight Jackers? I was looking into it and may go that route. The C36 aready has upgaded swaybars, but I'd like it to be lower and handle a bit better. Maybe a H&R cup kit..

[wichipong]

it should be...

but currently not running any pads..

[Vetruck]

Cutting Coils?! OH MY.. just kidding, theres always that age old debate. You know what you are doing though...

How come you got away from the Weight Jackers? I was looking into it and may go that route. The C36 aready has upgaded swaybars, but I'd like it to be lower and handle a bit better. Maybe a H&R cup kit..

Its the Mrs daily driver and she doesn;t want to get stuck driving my suga caddy for a week or more while I have it all torn down, grind and welded up. The Caddy is the only car she can drive of all my vehicles and she thinks it's a boat and is scared of it. Weightjacker would probably be fairly easy, but once I commit to it I am kindof guessing at spring rate- and if its not correct I can not go back to the conventionals- it would be down until I get the next order and reset it again until its got the correct feel and travel, basically I don;t want a divorse before I am even married. It's a fight waiting to happen if I pull her car down for really something that is not necessary. The other method is really easy and will work fine for what I need to do.

Cutting springs is a fine practice as long as you understand what you are doing and how the spring works, what the rate increase will be like and if it will go into coilbind or bounce off the bumpstops etc. i am a suspension guru, I have all of this handled. I need to deal with alignment and new arms also when I do all this so going weight jhackers right now also will be a nightmare in the lirttle down time I can afford on it- Now if the car broke and is down, that's another story- but me purposely taking it down? I ain't a stupid man...as slang would have it.

I have one last thing I need to research- that is "did Mercedes use the same rate spring on the front of both the C220 and the C280- but only change the spring pad to a thicker one to compensate for the heavier engine?" I am going to check into this right now.

[Vetruck]

I have one last thing I need to research- that is "did Mercedes use the same rate spring on the front of both the C220 and the C280- but only change the spring pad to a thicker one to compensate for the heavier engine?" I am going to check into this right now.


At least I know what to look out for- Low and behold my assumption was correct. They use either a #3 or #4 spring pad with the same spring. So going a 94 C280 spring in my 94 C220 would be the same exact part #.

Looks like Ill have to order some Eibachs for the 96 C280 and some post 96 #1 spring pads to accept them. I will order the spring pads first since they are cheap in cost. I can measure them and confirm if they will fit the diameter- Which thank you Wichipong for your response- I also do not see why they would change the spring cup. The spring design I can see changing, it appears the later years can utilize a barrel type spring which is much lighter weight and more laterally stable. The rears I will probably still keep the stockers and trim them to height- then add the larger swaybar- I doubt I would use the Eibach rears. I like that Eibach rears are progressive, but itf the rate climbs too much it will most likely ride harsh with the Konis and the larger rear bar. I wold rather have the larger rear bar rather than the stock rear with stiffer overall rate prgressive springs becuase t he car will still lean into corners and not rotate like I want it to.

I should also note that I know why Mercedes changes the spring design. The front springs on this car will make distrotion rubbing noise- kind of a rubbing pop- whe the sometimes deflect when one wheel travels over a speedbump and not the other. I am sure they had customer complaints about srping noise by the end of 1994 and by the time the change was processed they outfitted the production line by early 96- thus the change in spring pads and spring shape......See, we are al learning something here about these cars and why changes were made. That is a good reason for the upgrade. I figured a C280 spring would be a steeper coil ranp in windings so if I installed it onb the lighter C220 and trimmed it thenn I would not have this issue- I just did not discuss this part with everyone until now. this is what I mean on understanding spring dynamics- turns out its the same part # so if its doing the noise on this lighter car- then the smae spring will do it even worse on the slightly heavier nosed C280 of that year- They didn;t use two different spring rates for two different cars like they should have- cheaper in production line costs.

[Vetruck]

Ive also seen where they use the same exact spring in the C230, and the Kompressor Sport230 as they do the C280 and the C36. Just different Sping pads there also as well as different swaybars. It was all based on the same springs and ride heights event thought the cars were different weights. The C36 is the heaviest and used the thinnest pads- but they put larger swaybars on it to give it a little extra support for cornering performance over the slightly lighter c280. Once you figure this stuff out, its was really a simple production line engineering feat to keep cost down- Leave it to German engineering.

[Dearlove]

hey mate, ive been away a few days and funny you bring this up.

For my c36 I was going to cut half or 1 coil off the front and go with a thicker pad, increasing the spring rate but not lowering it too much

As for cutting the spring, as long as when the suspension is at full travel the spring is still slightly compressed (as in its not going to fall out) it'll be fine.

Also with the different spring shapes, so you're saying with your 94 the top of your spring is tapered (flat on top)? and you say this goes to 96? I'm surprised because my c36 isn't like this (my 190e was tapered)

[Dearlove]

just went and took a few shitty iphone pics of c36 springs in case anyone didn't understand
http://i363.photobucket.com/albums/oo72/dearlove88/076_zpsc018d6a0.jpg (http://s363.photobucket.com/user/dearlove88/media/076_zpsc018d6a0.jpg.html)
http://i363.photobucket.com/albums/oo72/dearlove88/075_zpsda4b50c0.jpg (http://s363.photobucket.com/user/dearlove88/media/075_zpsda4b50c0.jpg.html)
http://i363.photobucket.com/albums/oo72/dearlove88/074_zps84712863.jpg (http://s363.photobucket.com/user/dearlove88/media/074_zps84712863.jpg.html)

[Vetruck]

Thank you Dearlove. That last pic is great. I am assuming it is a NON-cut factory C36 spring since you said you 'were planning on cutting"?

If that assumption is correct then you have an 8 1/2 coil wind spring. I am almost certain without going out and looking again that the one I have in there now has alot more windings and a thincker wire- thus the coilbind issue. That is a lighter weight spring then what I have which is also nice. I will need to count the winds and the diameter of hat I have. I do not have its freee height lenth, but if you could get me your info since the spring is out- that would be fantastic. What I need is wire thickness, outside diameter, and free height. I will count my coils and wire thickness and outside diameter for now and then get the free height when I remove it. With your info I can try and calculate what the spring rate is on that C36 coil.

[Vetruck]

Thank you Dearlove. That last pic is great. I am assuming it is a NON-cut factory C36 spring since you said you 'were planning on cutting"?

If that assumption is correct then you have an 8 1/2 coil wind spring. I am almost certain without going out and looking again that the one I have in there now has alot more windings and a thincker wire- thus the coilbind issue. That is a lighter weight spring then what I have which is also nice. I will need to count the winds and the diameter of hat I have. I do not have its freee height lenth, but if you could get me your info since the spring is out- that would be fantastic. What I need is wire thickness, outside diameter, and free height. I will count my coils and wire thickness and outside diameter for now and then get the free height when I remove it. With your info I can try and calculate what the spring rate is on that C36 coil.

[Dearlove]

give me 10 mins :)

[Dearlove]

free length - 377mm
wire width - 14mm
OD - ~109mm

[Dearlove]

and its 8 & 1/3 windings

[Dearlove]

found a few calculators, I'm guessing the material would be close to piano wire?

[Vetruck]

free length - 377mm
wire width - 14mm
OD - ~109mm
8 1/3 windings


So you have basically in inch figures-

C36 spring

.551 wire
4.25 OD (3.7 mean diamter)
8.33 active coils
Rate: 307 lbs per inch travel.

C220
.551 wire
4.25 OD (3.7 mean diameter)
11 active coils
Rate: 233 lbs per inch travel.

I estimate mine to be a free height of 15-16". lets use 15.5 for an approx. If my compressed static height is 11.5" aprox, then my aprox effective static compressed rate would be 4 x 233 lbs = 932 lbs when loaded.

yours would be about 11.5"compressed,rate of 3.5x 307 = 1075 lbs when loaded.

You have a tad bit heavier engine by probably 100 lbs, but your car also rides more firm so the extra 75 lbs in free rate is justifiable. That would be quite a firm spring for use in my lighter car- and then also upped a little more with the aprox full coil Id need to cut off to get my car lower to the desired ride hieght. BUT REMEMBER- even though I am looking to use your C36 spring cut and slightly higher rate on a lighter car, you also have the larger swaybars that I do not have up front- so that washes a little back out onto the table.

Take a look at my picture below- you can totally see where the early design c220 and c280 cars go into coil bind and make spring rub noises against the top can. This is the front of my car earlier today.

[Vetruck]

GDDDD/8NMMM

G=Torsional modulus for steel [11.25 x 10(to the power of 6)or 11,250,000
D=Wire Diameter in Inches
N=Number of Active Coils
M=Mean Coil Diameter in Inches. Mean Diameter is:
I.D. = 1 Wire plus inside Diameter
O.D. = 1 Wire minus outside Diameter
8=A Constant for all Coil Springs

So you equate for the C36 spring by using-

11,250,000 x .551 x .551 x .551 x .551/ 8 x 8.33 x 3.7 x 3.7 x 3.7

[Vetruck]

Now if I cut 2/4 a coil off the c36 spring and installed it into the C220, it would give me a static rate of 341 lbs, a free height of 10% less as well as 3mm of pad thickness loss. So a combined motion ratio drop to about 13.25" free height and compressed with the same 932 lbs it would take me to about 2.75 less height when compressed or 10.5" static compressed height. At the motion ratio of about helf, that would drop the fender gap of about 1" (good starting point to be safe) and maybe even more than 1.5" drop. Bes to error on cutting short at first, and installing it a few time until I get the correct height.

The most important thing is this C36 upgrade into my early C220 look very viable and would shorten the overall wheel travel properly without having coil bind issues which are also present in the early spring design. I would have a lowered car with more gap between the active coils.

This is not all exact science, but you get and idea of a proprtionate starting point that purchasing a few $10 spring pads and a $135 set of front C36 coils new would be a low cost experiment to quickly execute- and if its not a decent ride? I simply put the stock coils back in and try again. The rate going from C220 to C36, and then to C36 cut are not equivilant. the cutting rate only goes up about 30% compared to the changing rate. So the car gets a good boost in spring rate to support the lower stance and keep it off the bump stops- the koni shocks have plenty adequate rebound damper to control heavy recoil rates of the firmer springs when one impacts a pothole indepenantly. Remeber, I am keeping the smaller stock fron swaybar.

I now have a game plan. Thank you all for helping with info.

[Vetruck]

Also lastly, by just cutting the stock C220 coil, the rate would not go up enough and the car would travel into the bumpstops or hit the fenders with the tires at the same ride height. The rate would not go up enough to support the limiting need in travel- this is why the heaveier C36 springs are needed. It's like putting big block chevy springs into a small block car- I am lucky I have the lightest version of the W202- gives me several options to work with as well as spring pads to correct the rate and ride height. I love this Mercedes spring pad system, it is alot like how you would dial weight jackers to keep a consistant ride height regardless of spring rate.

I'm a sucker for the liught nose versions of cars. I ge tthem to handle so well they take own any of the larger engine cars of the same type at the track. i did this with a little V6 Camaro and won a few dollars in my day racing V8 Camaros of the same type. This car turned circles on them because of the light weight motor. I could carry my speed faster through corners which ment less braking and less having to speed back up. makes for a fun car to run around town in as a good milage daily driver

[John Jones Jr.]

Great posts Vetruck.

[Dearlove]

yeah i've thought about getting a 97 or later c280, with the v6 for that exact reason