The problem is that these mods will look very silly on a W123. He will end up with a 125HP sedan that "looks fast" to a 12 year old.

I had a 350mm Momo steering wheel on a 914, it was quick but it took some muscle to turn.

__________________
'82 300D (563K)
'83 240D (250K)
'04 E500 4matic (69K)
'83 BMW R80/ST (36K)

I came out of a coffee shop and walking thru a parking lot, when i happened upon what seemed to be an immigrant busboy behind the restaurant with a 1970ish corolla. Upon the front panel above the front wheel, he had sprayed painted the words TOYOTA with a stencil. It looked like he did not have enough paint because you could see the color of the car through the painted logo and the edges were not sharp. Obviously spray paint over a paper stencil.

You can get clamps for your springs to drop your car by a coil or 3, try it on for size w/o cutting your springs. Bit of work to wrench them down, it is. Make sure no that no brake or fuel lines are in the way of the clamps or suspension.

If you choose to drop it, you'll probably need to have it aligned. Camber and front wheel toe will couple w/ suspension travel. IIRC, Porsche started putting roll steer into the rear wheels to tame the way the rear end breaks loose, read about it ~1995 or 7.

[QUOTE=t walgamuth;2635038]You don't take MY WORD on this ? What is this forum coming to ?
Your butt is telling you one thing... me something different...

I am not a spring expert... but for this thread lets assume that I AM.

A coiled spring with regular matching coils ( meaning the same size and existing directly above each other ) .. .like most automotive coiled springs...have a variable rate of springing... starting in the free state uncompressed state determined by the type of metal, the wire size, the heat treating method , etc. and it goes from that starting point to ZERO.... NO SPRINGing at ' fully compressed'.... so there is a curve in the spring rate which nearing compressed increases very fast.

In other words.... this is a dynamic system and what your butt is feeling is the result of the suspension GETTING to that increased resistance section of the curve FASTER... thus making the spring feel stiffer...
when in fact all the result is from the reduced travel available due to shortening.

But the metal in the spring is not stiffer due to cutting them shorter.

I enjoy talking about these finite physics things... but I totally agree with Tom on the big picture... these cars are not going to do what some who have experienced firm rides in smaller cars might think is only a suspension ' fix' needed...

At the same time... if your car has old springs, old tires, old shocks , old bushings, old antisway bar..... and you are entering corners too fast and braking into them....as compared to slowing properly before hand and accelerating out of them... then there are some things which you can do to bring it back to nice MB ride and cornering you deserve.... or most of you deserve.. LOL

You do know Bilstein HDs can be revalved to your specs, right?

Any benefits to putting a strut brace?

Ah,, nomenclature moment..
what do you mean by ' strut brace' ?
It may already have what you are envisioning...

Answer
 

Just completed a 300CD for the exact same issue a few days ago.

Typically on the W123 chassis:
I assume most of the roll is in the rear.

#1. New heavy duty shocks.
#2. New differential mount.
#3. New sway bar links.
#4. New springs + shims.
#5. New front sway bar end bushings = on the end of the bar at the upper control arms.

OOOHHHHH,,, wish you had done that to my car...
how much was the total bill ?

Slow Down!!

Do you mean i can send my Bilstein Comforts to Bilstein and they will revalve it to HDs?

If so, then i should call them and ask how much.

thanks

since it takes somewhere less than 20 hours to do the front sway. it seems like someone should make a brace bar to control the front sway that fits inside the engine compartment. it would take less time to install.

Is there an issue with space to do this.

Doing the front sway bar is a big job because lots of other things have to be taken out and put back in to replace it..
but where do you think something could be attached TO which would accomplish what the antisway bar does .... which basically uses the OTHER WHEEL position to modify with spring action the following of the body towards centrifugal force.

tomorrow is the last day to buy an alignment certificate at the mercedes dealership in carlsbad. 79 dollars. i had better drive down there and check it out so i am offline soon.

aftermarket uses under the body to mount additional antisway... on other cars... mostly for rear though. hard to do in the front with the engine/tranny...

Neat read.
http://www.motoiq.com/magazine_articles/articletype/articleview/articleid/1712/the-ultimate-handling-guide-part-v-the-one-unforgivable-sin-overlowering-your-car.aspx

The wheels are not refinished yet and i am planning the next push and trying to get it right the first time.

1. BBS RS 7 x 16 Nexen N3000 205 50 16 ET 24 Diameter =24.1
2. BBS RS 8 x 16 Nexen N3000 245 45 16 ET 11 staggered set D = 24.6
3. OEM oil pan protector
4. KMAC Camber adjuster rear
5. front 3 inch spring cut
6 rear 3.5 inch spring cut

1.
2.
3.
4.
5. Wait for group buy perfect sway bars front and rear.

[QUOTE=leathermang;2635322]It is my understanding that the actual springing from a coil spring comes fromt the twisting of the metal in the coil. If you picture a straight bar like in a torsion bar and then take a given section and reduce its length you will increase its ability to resist twisting, so shorten the coil you stiffen the spring. Hence a stiffer spring of a given diameter wire if it has more coils is softer than one of the same height with less coils.;)

Your scenario is also true, you would reach coil bind quicker in a shorter spirng with a given movement.;)

Tom, lets assume that all the actual in these springs in question is the same.. unless you can site differences.... usually ' spring' steel is about the same composition (?)...

Hence, your statement " Hence a stiffer spring of a given diameter... " brings to question how a spring is made stiffer WITHOUT increasing its diameter...

The unit movement ... any particular number of inches of that spring..if comparing same diameter.... will twist the same amount under the same load...
by increasing or decreasing the length of the piece of metal you are increasing the TOTAL added movement of each of those increments... not changing the unit stiffness of the metal in that spring..

I and my family owned about 7 Chrysler products in the era of those longitudinal torsion bars... a wonderful space saving design. The only drawback was that if they were not set to within one quarter of an inch of each other.... rolling and swaying was introduced to normal driving... and few people knew to check and set ( easily set ) that..

Have you seen springs wound to where they can be compressed to ' flat'... so the coils do not bind.. but lay beside each other in total compression ? I do not remember where I saw them ... but thought they were very smart... the same with springs IN ELONGATION... which do not suffer the increased resistance of coil spring binding... and which I think is the next wave with heavy batteries for electric cars needing softer suspensions...

i believe some of y'all are overlooking one important factor in this whole idea...oversteer is so much FUN. i often miss my gas turbo volvo wagon with fat sways front and rear and the boost turned up. oversteer on demand is fun. the other day, when it was misting, on a deserted chunk of streets, i was getting the 300sd sideways and it was awesome. it made me want to go home and start wrenching.



SUPAAAH DOHRIFFFTOOOO

Do you not understand that changing the length of the rod without changing the makeup or diameter of the material will change its ability to resist twist?

Example.....take a 1/4" rod that is 2' long and take a 1/4" rod that is 4' long...the longer rod will be easier to twist, right?

Now take that rod and coil it up into a coil spring. The longer one will give more.

So cutting the length will make the spring stronger in resistance to a load imposed.;)

The longer one will give more...
but you have not made it stiffer...
you have simply doubled the wire length and it is giving under the same load per increment of length.
Cutting the length will make it bottom out faster... but does not make it stiffer.

I have been spoiled!

My now sold 190e 2.3 16V Cosworth was designed to go racing and drives as though it was on rails with almost no body lean.

Similarly my M3 also is designed to drive as though it is on rails with almost no body lean.

Neither car is soft or "wallowie".

My E300 is very wallowie and I plan on redoing the sway bar bushings and end links and then I plan on simply doubling up the bars for a simple cost effective solution. As weather permits I will do the work and report back. I am realistic and expect less body roll. The E300 will never be a Cosworth or M3 but I believe there is room for lots of improvement.

Watch and see almost no body roll

Spring design
 

SPRING DESIGN
http://home.earthlink.net/~bazillion/design.html

RESOURCES AND LINKS
http://home.earthlink.net/~bazillion/resources.html




.

Even the AMG tuned 500CE had some body roll

http://s3.images.drive2.ru/car.journ...0-original.jpg

The W115 had little strut/shock tower braces that would go from the firewall to the towers. Cars with McPerson suspension really need these braces BTW.

AFAIK, only the HDs can be revalved. Don't quote me on the exact numbers but I think they are like 260lb or so but there is nothing stopping you to have them at 400lb. Difference between doing this and using Koni adjustables is that you would have a known and consistent number.

thats my dream car btw. I actually have a red coupe parts car sitting. Just needs a lot of stuff. The interior is molding bad (steering wheel is growing) and needs lots of parts. Make it just like that one but with a 606 tuned to about 275 hp I think would be perfect. Or a black SEC

What are the steps to do this.

What is a budget to do this.

IIRC all that is needed is to remove the battery tray, separate the mbc from firewall and jack the rear of the trans up....

BTW I recently replaced my front spring pads some months after the springs. They really do smooth out the ride a surprisingly amount.

Some roll is good in these cars. If you look at the way the rear end geometry is setup. Toe adjusts with camber, its certainly a precursor to the multilink rear.

reduce roll
 

SORRY, can't resist...

best way to reduce roll is to stay away from DONUTS.:P

My vote is for bilstein hd's, I experienced much less body roll on the freeway after putting them in.

I don't understand your first three lines and I disagree with your third. Tonight I will try to decifer what Roy posted.

Let me try:

Think of each coil of the spring as a twisted torsion bar. Assuming you are within the design operating range of the spring, the force exerted by that coil is proportional to the displacement of that coil (Hooke's law). So if my spring is 10 inches long and has 10 coils, I can think of it like 10 small springs stacked up.

Lets say I depress the 10-inch spring by 1 inch and feel 100 pounds of force, that means each of the coils was displaced by 1/10-inch and exerted 10 ponds of force. If I depress the spring 2 inches, I will feel 200 pounds, etc.; until I exceed the operating range of the spring.

Now, if we remove one coil we have a 9-inch, 9 coil spring. If I depress this spring by 1 inch, each of the coils will be displaced by 1/9-inch and the resulting force will be 11.1 pounds. However, I only have 9 coils contributing to the total force so, 11.1 x 9 = 100 pounds.

The result is that the overall spring coefficient is the same for the shorter spring, but it has less usable travel. In both cases a total displacement of 1 inch results in a force of 100 pounds. Shortening the spring does not make it stiffer, just shorter.

Wrong.

Shear does not accumulate like displacement through the length of the spring. If it did, there would be no reaction at one of the supports- either the spring perch or the LCA.

Viewing each coil as a free body is useful, and spring body connects the equal and opposite (in a static case) forces at the spring perch and LCA via shear.

Consider the spring again 10" 10 coils, 100lb/inch. For a 100lb load, each coil sees 100lb, and deflects .1". The spring constant of each coil is the force over the deflection, or 100/.1 = 1000lb/in.

Cut a coil off, 100lb load, deflection is 9x.1" or .9". To achieve 1" deflection, each coil deflects 1/9" = .111", the reaction is 1000*.111=111 lb. The new spring constant is 111 lb/in.

Another way to look at it is each coil being in series w/ the next.

http://en.wikipedia.org/wiki/Hooke%27s_law#Multiple_springs

Springs in series add like resistors in parallel:
If added in series, 1/k = Sum(1/k1 + 1/k2 ....)

10 coils 1/k = 10 * 1/1000 =.01
k = 1/.01 = 100

9 coils 1/k = 9 * 1/1000 = .009
k = 1/.009 = 111

So you are saying cutting a coil off increases rate by 10%, right?

Moon161, Do you want to correct the sentence fragment which says 'each coil sees 100 lbs' ... you have the math in the next clause correct for your initial example ..but each coil only sees 10 lbs... and does deflect .1 inch
before we go on ?

Tom, he is trying to say that ..but that is not correct.
Given the same load.. the 100 lbs... spread between either 10 coils or 9...
the deflection per coil is the same.. but with 9 as the load is increased it will encounter the limits of its ability to compress.. thus feeling stiffer... and since we are assuming the load of the car in question remains the same.... each coil still represents a deflection of one inch per 100 lb load .. so the short one is not stiffer.. only shorter and has less travel to offer.

( the load is increased in corners for instance ...and less roll will feel like stiffer.. but will just be less travel available.)

Pretty sure my example is correct. Get comfortable with free body diagrams, & refer to a physics, machine design or solid mechanics book for further explanation.

"For a 100lb load, each coil sees 100lb,"
Your choice... but for 10 coils and one inch deflection per 100 lbs your math of .1 inch deflection is correct.. but your statement that EACH coil sees 100 lbs is not.. your own math does not match your wording...

Coils don't have eyes, right?:P

I believe you are correct. Based on a free body diagram approach, each coil will be exposed to the full load and will respond accordantly, therefore the spring with the greater number of coils will have more total deflection than the spring with fewer coils for the same load.

Sorry, I confused myself trying to do statics in my head. My previous post is incorrect because I didn't recognize that each coil will respond to the full load on the spring, not just a portion of the load. Good catch.

Ours are SPECIAL coils..... can be used by seeing impaired as 'guide springs'....

Each coil in the spring will respond to its PORTION of the full load on the spring.. even his math agrees with that..
Each coil does not ' see' the 100 lbs... but only ( in the 10 coil example ) one tenth of the 100 lb load...

That was my mistake too, if you think of the system as 10 small springs stacked on top of each other, each one has to transmit the full load from the section above to the section below. Each spring section will be displaced a specific amount due to the total load, not just 1/10 of the load. That is consistent with the equation for springs in series (1/k = Sum(1/k1 + 1/k2 ....)), which you can look up anyplace.

My First Kill in my 300CD!!!!!!
 

I was stopped at a red light in front of a freeway on ramp. From behind i hear this rumbling, and i look in the rear view mirror. I have been told my car is slow and I did not want to get run over from behind...so I hit the pedal firmly.....To my surprise I pull away and after 100 yards I look in my rear view mirror and he is 60 feet behind and pushing hard, but I am pulling away. Wow, my first kill in my 300 diesel.

Now i just have to figure out how to paint a small picture of a UPS truck on the side of my car.

Consider a series of sewer pipes, placed end to end, with sewage flowing through it at a constant rate, higher at one end than the other. The decrease in sewage height (head loss) due to friction is cumulative from one end to the other- (Ref. First Law of Civil Engineering). The head loss is distributed evenly between sections, but the full amount of sewage goes through each pipe. The principal is the same- loss is distributed through serial elements, load is distributed through parallel elements.

HIS MATH shows springs with a deflection of one inch per 100 lbs..
HIS MATH figures that at .1 inch deflection.
The total load ...100 lbs... is spread between the 10 coils ..thus causing each to bend .1 inch... his example set the deflection rate of one inch per coil per 100 lbs load..
Don't give up so fast on your initial judgment..

Sewer pipes have nothing to do with this ' feeling stiffer' spring question.

Good article here double up sway bars article

I purchased my sway bars from a wrecker for about $50 for both front and rear sway bars. Bushings are extra.

Too cold and too much snow to play with doubling up before spring.

The front end result should look something like this.

http://www.vwbughead.com/412fast/412...le%20sway1.JPG

another full thread

OK. That double sway bar url clears up a lot... They are not trying a full hookup of two bars.. which I could not visualize as having room to do..
but are ' doubling up' on the interior length of the bars... and cutting the attachment ends off the originals...