Top 3-5 cost efficient ways to decrease body roll? - Page 5 - PeachParts Mercedes-Benz Forum

English Bulldog · #61 01-13-2011, 03:13 PM

Quote:

Originally Posted by leathermang

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

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.

leathermang · #62 01-13-2011, 03:29 PM

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.

English Bulldog · #63 01-13-2011, 03:30 PM

Quote:

Originally Posted by moon161

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.

we were just going to measure it. can cut a partial coil right?

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.

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.

vstech · #64 01-13-2011, 03:58 PM

Quote:

Originally Posted by leathermang

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.

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...

moon161 · #65 01-13-2011, 04:20 PM

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

English Bulldog · #66 01-13-2011, 04:45 PM

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.

t walgamuth · #67 01-13-2011, 04:47 PM

[QUOTE=leathermang;2635322]

Quote:

Originally Posted by t walgamuth

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

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.

leathermang · #68 01-13-2011, 05:11 PM

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...

pgringo · #69 01-13-2011, 10:01 PM

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

t walgamuth · #70 01-13-2011, 10:21 PM

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.

leathermang · #71 01-13-2011, 11:19 PM

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.

EDBSO · #72 01-14-2011, 01:09 AM

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

whunter · #73 01-14-2011, 01:59 AM

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

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

.

MBeige · #74 01-14-2011, 02:26 AM

Even the AMG tuned 500CE had some body roll

dalek · #75 01-14-2011, 02:34 AM

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.

Quote:

Originally Posted by English Bulldog

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

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.