Wondering ??
Is the sway bar in an 87 16V 190E bigger than the stock bar on a 85 190E 2.3 8v
Thanks

Front US model 201 anti roll bars:

201 323 52 65 All 190E 2.3 and 190D 2.2
201 323 71 65 All 190E 2.6 (measured 25 mm)
124 323 19 85 All 190E 2.3-16 (measured 23.5mm)
201 323 79 65 All 190E 2.5, turbo & NA


Rear US model 201 anti-roll bars:


201 326 36 65 All 190E 2.3, 190D 2.2, 190D 2.5
201 326 38 65 All 190E 2.6, 190D 2.5 turbo (measued 14.2 mm)
201 326 33 65 All 190E 2.3-16

If anyone can fill in the rest of the thickness dimensions I'd appreciate it.

Duke

Yes

2.3 22mm front 13mm rear
16V 23.2mm front 15mm (?) rear
AMG W201 28mm front 17mm rear

the 190D 2.2 has larger bars than the 190E 2.3

I rewrote my previous post with all the anti-roll bar info I have on US model 201s. The part numbers are from the MB parts book. Measurements are my own for those I was able to measure.

Duke

Duke, the part number I have for the 2.3-16 front bar is 201 323 78 65
The 124 part number you have is for the rubber mounting.

do u have the part numbers for the 500E and E60 front bars by any chance?

Tom

The front bar for the 92-94 500E is 124 323 72 65

Check this Excel Spreadsheet: http://www.meimann.com/images/mercedes/W124_sway_bars/124_swaybars.xls

Thanks,!!! I was suspicious of a 201 anti-roll bar beginning with "124" because differences in chassis dimensions mean that 201 and 124 bars are not interchangeable. I guess I copied down the wrong number when I was jotting down the data. At the time I was looking for a slightly larger rear bar to reduce understeer. The parts book does not provide thickness, but knowing what models have different part numbers told me where to look.

It appears that the 16V may have a slightly larger rear bar, but I dropped the idea after doing a track event and realizing that both the suspension and gearing needed major rework along with the addition of a LSD to be track competent. Being as how I have two other cars that are very track competent with just minor suspension tuning I decided to never take the 190E 2.6 to the track again and just use it for normal driving and long distance touring at which it is superb.

The 16V gearbox and LSD differential and a 3.0L M103 engine would make the 2.6 much more sporty, but I decided it wasn't worth the cost and effort to do all the modifications. It's too bad Mercedes never build such a 190E 2.6 "Sport". I was never attracted to the 16V because I wanted the inherent smoothness and higher torque of a larger I6, and the 16V was too close in concept and performance to my Cosworth Vega. The shim under bucket valve adjustment also turned me off. The CV is shim over bucket and just requires a special tool to swap shims.

I don't have any information on anti-roll bars for any models other than 201s. I just went to the dealer and found a friendly parts guy who looked them up for me. Anyone else should be able to do the same for other models.

Duke

A stiffer rear bar isn't going to reduce understeer, it's gonna reduce roll oversteer instead.

If you make it and the front bar stiff enough, you can get the W115 problem -- it will corner hard enough to force the front outside tire off the rim! This problem was "cured" in later models by reducing the sway bar stiffness some, to allow more body roll. This unloads the front tire and causes the rear to lift and start to slide, permitting the driver to retain control and recover gracefully (as in on the road instead of in the ditch or up alongside a tree or something). It's not as pronounced in the multilink rear end since you don't get the camber/toe changes you do with the semi-trailing arms, but it's still there.

I've been told the multi-link rear end is less forgiving than the semi-trailing one, but I've never driven any of my cars hard enough to find out -- not possible with the 220D in any case!

I've not noticed any understeer to speak of in the W124 (nearly identical to the W201 chassis suspension), so I'm not sure why you would want to "reduce" it.

Peter

__________________
1972 220D ?? miles
1988 300E 200,012
1987 300D Turbo killed 9/25/07, 275,000 miles
1985 Volvo 740 GLE Turobodiesel 218,000
1972 280 SE 4.5 165, 000 - It runs!

I've been chassis tuning with alignment, anti-roll bars, and shocks for a about 30 years, now. The steady state understeer/oversteer balance of a car is determined by weight distribution and front/rear roll stiffness distribution, but suspension architecture can play a major part in transient behavior. Most production cars are set up to have mild to significant understeer. Less understeer is usually rewarding to a skilled driver, but a neutral car can sometimes transition to oversteer at the limit, which is the reason why most OE suspension calibrations have plenty of "safe and sane" understeer designed in. Basic suspension architecture has a significant influence on transient behavior and some are better than others with many IRS designs being more twitchy than a well located solid axle.

Because of its higher front weight distribution, the 190E 2.6 has more inherent understeer than a 2.3, and having owned both, the difference is noticeable. My former '84 190E 2.3 was closer to neutral (less understeer) than the 2.6 without having any tendency to snap into oversteer. For cars equipped with both front and rear anti-roll bars, a slightly larger rear bar will increase rear roll stiffness and move dynamic response closer to neutral. Since the anti-roll bar's contribution to roll stiffness varies as the fourth power of its diameter, even a 1 mm change is usually noticeable.

Roll steer is usually a secondary effect and is a function of the suspension architecture and detailed design. A small amount of roll understeer can be desireable by having the rear wheels steer slightly into the direction of the turn with increasing roll, which adds stability if it is not excessive. At the front, roll understeer is achieved with geometry that causes the front wheels to steer opposite the direction of the turn will increasing roll.

Achieving slight roll understeer with a solid axle suspension is fairly easy by the arrangement of the control linkage and bushing compliances. Roll understeer is achieved on IRS designs with slight toe-in with jounce and toe-out in rebound, but it should not be overdone as lifting the throttle will alter pitch moment, and this can lead to trailing throttle oversteer, especially on designs that have poor pitch control. This behavior is somewhat inherent in semi-trailing arm suspensions because they have fairly large toe and camber change with vertical suspension movement along with relatively poor anti-squat and anti-lift characteristics, which together consititute pitch control.

The five link rear suspension pioneered on the 201 models maintains close to constant toe, camber, and track through most of the suspension travel range, and has very good pitch control. It is essentially "neutral", which yields both stability and good response to small changes in roll stiffness, without introducing any untidy secondary effects, and whatever roll steer is desired for stability can be designed into the front suspension.

My two favorite rear suspensions are the Mercedes five link and the "torque arm" solid axle in my Cosworth Vega. Both have excellent wheel geometry and pitch control and can be tuned to have minimal understeer without a tendency to snap into oversteer in nine-tenths driving situations or if you have to drop the throttle in mid corner.

My experiences with semi-trailing arm suspensions and three and four link IRS designs has been less than satisfactory. These all exhibit transient oversteer due to track, camber, and toe changes, and/or poor pitch control, and if they are tuned to be fairly neutral at seven-tenths, they exhibit a tendency to snap into oversteer at nine-tenths, especially if you lift off the throttle.

Considering that free body in space has six degrees of freedom, and it is generally desirable for the rear suspension to limit wheel movement to one degree of freedom, a five link design makes perfect sense.

Duke

Duke:

That 5-link design is one of the best -- and not too expensive, either, unlike some older "independent" designs (aka Corvette rear ends).

Thanks for the lesson, too -- never hurts to learn more.

I do know that the W123/W116/W126 suspension is somewhat more forgiving at handling limits -- gives the driver plenty of warning that you are getting close to losing control and allows one to recover without sudden changes in direction, etc. This IS accompanied by somewhat unnerving rear end movment. It "jacks" some and the back end starts steering out, but this is a good thing compared to the W114/5 chassis -- the antisway bars are SO stiff in that design that you can force the outside front tire off the rim before the rear starts to slide. Very little body roll.

Needless to say, gracefull recovery is NOT possible that that tire off the rim.

this applies to the W107s as well.

Peter

__________________
1972 220D ?? miles
1988 300E 200,012
1987 300D Turbo killed 9/25/07, 275,000 miles
1985 Volvo 740 GLE Turobodiesel 218,000
1972 280 SE 4.5 165, 000 - It runs!