I know a few people have written reviews somewhere in this forum, try searching for "strut tower bar" or something like that in the forum for their write-ups

 

Checking that now. Much thanks Nolan.

 

http://www.benzworld.org/forums/showthread.php?t=2011393 one of the more in-depth ones I had bookmarked

 

I remember the thread about these bars and how it made the forum roll and shake around! For my part I think I compared these bars to the "Kings new clothes" story, it all developed into a >>>

 

Nolan thanks for this link to the very favorable report by Pete S, about this strut bar. Reading about this invention for the first time today, I remain slightly puzzled as to why more Benzworld writers have not acquired this strut brace bar so as to experience the dramatic road handling benefits offered by this subtle yet effective suspension enhancement device.

Bearing in mind Red Liner's reference to the possibility that this particular suspension upgrade may not prove to be as beneficial as the product advertising suggests, I imagine that this after-market structural connection between the front shock-absorber upper mounts could produce a much more noticeable handling improvement on the pot-holed roads of the Third World where I drive, than would be experienced by drivers on the comparatively smooth highways in Europe and North America.

On the other hand though, there is the possibility that after prolonged driving on rough road surfaces, the frame rigidity imposed by such a retro-fitted strut brace may result in faster than normal wear of suspension components, or worse still, breakage of critical suspension support surfaces in the vehicle front end.

As a minor digression, some years back I attempted to "upgrade" the rear anti-roll bar in a 2001 Jeep WJ Grand Cherokee, after being won over by the advertising pitch extolling the improved rollover protection offered by the after-market heavier-than-stock gauge rear anti roll bar. Cutting a long story short, I did not notice an appreciable sense of roll-axis stability with the new rear anti-roll bar installed, and wound up returning the stock rear anti-roll bar when its mounting bracket on the vehicle frame got ripped clean off under the added stresses inflicted by the "improved" heavier gauge anti-roll bar.

Unexpected suspension stresses caused by after-market undercarriage components would be less of a concern for lucky drivers tooling along the pristine roads of the West, but out here in the boonies where the roads range from marginal to lunar, I might be wise to wait and read a few more user reviews, before I go ahead and buy a strut brace bar for my 1991 500SL.

 

...I stumbled on a suspension modification that I have never encountered before anywhere...

Strut tower braces are not a new concept and were around when M-B designed the R129. I have seen them on production GM cars for years.

The brace appears to me to be an obvious improvement -- too obvious, in fact, and for me therein lies the rub. The R129 is such an over-engineered vehicle, and surely M-B would not have overlooked incorporating such a cheap component if they believed it would enhance the vehicle.

I am reminded years ago of Benzworld members replacing their stock crankshaft pulley with a lightened pulley from a vendor who claimed his product increased horsepower and fuel economy. Though it was proved that the product in fact was worthless, members who had purchased and installed the pulley reported back that their "butt dynos" had measured a great improvement. Perhaps there was a placebo-like effect.

If you purchase a strut tower brace believing it will improve your vehicle in some fashion, I believe that you may perceive that improvement and be pleased with your purchase regardless of whether or not the brace actually has any real effect.

 

Strut tower braces are not a new concept and were around when M-B designed the R129. I have seen them on production GM cars for years.

The brace appears to me to be an obvious improvement -- too obvious, in fact, and for me therein lies the rub. The R129 is such an over-engineered vehicle, and surely M-B would not have overlooked incorporating such a cheap component if they believed it would enhance the vehicle.

I am reminded years ago of Benzworld members replacing their stock crankshaft pulley with a lightened pulley from a vendor who claimed his product increased horsepower and fuel economy. Though it was proved that the product in fact was worthless, members who had purchased and installed the pulley reported back that their "butt dynos" had measured a great improvement. Perhaps there was a placebo-like effect.

If you purchase a strut tower brace believing it will improve your vehicle in some fashion, I believe that you may perceive that improvement and be pleased with your purchase regardless of whether or not the brace actually has any real effect.

Ha ha the placebo effect. Now that I am aware of this phenomenon as it applies to driver expectations after vehicle "improvements", the next big challenge will be learning to discern whether mechanical performance improvements perceived as a result of non-stock vehicle alterations are real and measurable, or merely figments of my own imagination, as I endeavor to rationalize the cost of the "upgrade".

On a serious note, one does wonder why this simple device was not part of the original R129 suspension design. Perhaps Mercedes auto engineers decided to discard the strut brace option for purely aesthetic reasons, in that the inclusion of a structural bar above the engine air cleaner could detract from the look of the engine bay, while also obstructing some routine engine service procedures.

This preceding paragraph is merely idle optimistic speculation on my part, as I try to banish the thought that the R129 designers actually found such a shock tower connecting brace to be detrimental in the long run, due to accelerated wearing out of related suspension components caused by the bar's addition between the upper shock mounts.

 

These struts really make the SL look cool when the hood/bonnet is open. Probably effective on the CLK Black series but on a R129; doubt does anything.

:|

 

The bar does stiffen up the suspension. Anything you can do to stiffen up a convertible will help. I have noticed that the cowl shake is greatly diminished. It is a little difficult getting it from Germany, but it was worth it. The only thing I didn't like was the red color, which looks out of place under the hood. I had mine painted black, which blends in perfectly. After seeing it on Pete's car, I had to have one. 5 minute installation. It took longer to get the tools together! I totally recommend this mod. The only negative is that it adds a few minutes to the removal of the air box, but it's only 2 bolts.

 

I think I will take the plunge and buy this strut bar. Between the number of driving hours racked up by Pete S, and by Jeff, behind the wheel of R129 cars fitted with these Weichers strut bars, any downsides to fitting this modification to the struts in a R129 would have been uncovered by now.

I found no R129 user reviews of the Weichers strut bar on Youtube, but every one of the user reviews that I have read, on this, and one other internet forum, have been enthusiastically positive, with no reservations expressed besides understandable disapproval of the curious lobster-red color scheme that is the only one evidently offered for the device, along with minor gripes over some difficulty in distinguishing the un-marked right from the left end of the strut bar, during the initial installation.

Regarding the possible detrimental effects of running a R129 equipped with a strut bar on poor road surfaces, I will find out first hand, as the miles and years roll by. If anything really disadvantageous turns up with respect to long-term installation of a strut bar, I will be sure and report my findings to this forum. Hopefully there will be nothing negative to report in this regard.

 

Glidescope you read the thread I started and I still feel the same way about it.

I don't think the engineers overlooked this, it's just a matter of who the target buyer is for a certain model and the SL was not targeted for the ultra high performance buyer rather the buyer that wanted to take a nice leisurely ride along a beautiful road with added power and style. JMHO.

Glidescope I don't know if they still offer it but they did have a aluminum version. I know one member bought it and was not satisfied because he said he could flex it with his bare hands, my guess is they didn't use a thick enough aluminum so I would stay away from the aluminum if it is still available.

It's not a "holy shhhh this is so much better handling now" difference but if you are type of person that feels a car in his hands and butt you will notice a change.

This is all I'll say. There was a thread that became a shit storm regarding cowl shake and if it did or didn't rub on the M113 equipped cars but that's in the past, personally I will not participate any further in those discussions.


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Pete my hat is off. I just saved myself some good money by reading the above post. Were it not for the timely advice you spelled out here, about the importance of choosing the steel strut brace over the flimsy aluminium version, I would have ordered the aluminium one for sure, because I would have assumed that unlike the steel version, the aluminium shock brace must have been designed to crumple in the event of a collision impacting one side of the vehicle's front end, thus minimizing the amount of force transmitted beyond the impact zone, by that connecting strut brace.

Reading your description of the aluminium strut bar being flimsy enough to flex by hand with little effort, my layman's deduction is that the load-bearing tensile strength required to transmit the impact forces involved without deforming is simply lacking in the aluminium strut bar, making the steel version the wisest option to choose,even if it is only shipped in fire engine red ha ha.

Regards and sincere gratitude.

 

I bought one for my 02 SL500 with the M 113 engine. I quickly sold it to someone else.

The bar didn't fit properly. It rubbed the air box on top of the engine, leaving red marks. There was no clearance what so ever. In addition, the abs break lines mounted in the firewall needed to be moved.

Waste of money, waste of time.


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From my understanding of the product description, Mike, the manufacturer of the strut bar does make mention that it would not be suitable for the 1999 and newer R129's fitted with the M113 engine, meaning that only R129s made before 1999 could be fitted with the strut bar, such that it does not make contact with the air cleaner once installed.

Well heeled punters gamble thousands of dollars at the blackjack tables in 'Vegas every day, so, despite being a man of comparatively modest means, I am opting to take a gamble on this strut bar, which costs far less than those high rollers lose without batting an eyelid, and, if Lady Luck is in a good mood, I may find that the road handling benefits mentioned by other users of this bar are real, and attainable for my 1991 M119-powered R129.

Definitely if I experience any adverse consequences to using this bar, I will post my observations here in this forum, to warn off any others who might be contemplating this modification.

 

I can guarantee you that he added that verbiage after my (and others) experiences with the bar. I do not gamble, as you put it with modifications to any vehicle I own. That would just be plain foolish.


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While casually reading through the R129 forum over at The Dark Side, I stumbled on a suspension modification that I have never encountered before anywhere, and which has earned rave reviews from several R129 owners who acquired this product from Germany...

Oh Mr Glideslope, not another victim of another wild goose chase? haha

The cheaper end of the mass car manufacturer market use combined MacPherson struts for cost reasons, where the spring and strut are combined so that the entire sprung force is transmitted to the strut tower. When the nose of the car dives under braking, the strut towers flex inwards. This alters the wheel geometry and leads to vagueness of steering generally and squirming under hard braking. The aftermarket cure is to install a strut brace.

Now, the R129 on the other hand is not a mass market design thrown together in someone's shed overnight. It does not use combined suspension struts. Mercedes engineers, being bright fellows with a larger pot of money at their disposal, decided to have a separate spring tower much closer to the main chassis rails supporting the wishbones. This means that only the damping force is transmitted to the strut towers, which consequently do not flex under hard braking.

If you believe that a strut brace will make a difference in a R129, go ahead and buy one. But before you do, try this test: -

Park car on level surface. Tape a length of string or para cord across the strut towers, but make sure it has a slight sag so that there is no tension in the cord. Get some help and push the front on the car down and watch the cord. If the cord dips by more than 2mm, you can be sure that your strut towers are flexing.

If the cord doesn't budge, take the money that you would have spent and post it to me! No don't do that. I've got enough tax problems already!

Regards
Rob

 

Rob, your description of the strut towers in the R129 having been designed not to flex, in contrast with lesser vehicles, is by far the most persuasive argument against adding a connecting strut between the two shock towers. I was literally moments away from clicking on the buy button when I read this post of yours, and now all of a sudden I am not so sure this would be a worthwhile expenditure. My predicament at this point reminds me of the joke about the person who remained terminally undecided about whether or not to enroll for an assertiveness seminar.

In the meantime, while my local shade-tree mechanic was replacing the front springs in my 1991 R129 this morning, he belatedly noticed that the control arm bushes and the sway bar bushings were worn, so after a brief rant about wishing I'd been told all this before I placed my initial suspension parts order, I decided to delay my purchase of the strut bar until after all the worn bushings are replaced with new ones, so as to take another test drive during which I will decide whether leave the stock suspension alone, or to go ahead and add the strut bar.

My lingering doubts about adding this after-market strut connecting bar arise more from speculation about possible damage or accelerated wear of other associated suspension components if the bar is added to a car driven extensively on washboard road surfaces, than from concerns about the strut bar not actually living up to its billing.

 

Rob, your description of the strut towers in the R129 having been designed not to flex...

Well, the test I was talking about is a way to measure that flex. One things for sure, the R129 strut towers will flex, but no way near as much as other makes that use combined struts/springs.

The biggest culprit of vagueness and tramlining in the R129 by far is the steering box, Pitman arm, damper set up, and of course wear on the suspension bushes.

Get out there and do the test! Lets hear your feedback. I can hear the wives of the US right now... "what the heck are you doing with that string and tape fool?!" "Ahem... it's technical dear"... haha

 

I can confirm that the application guide was only changed after the shhh storm thread where a few members with M113 engines complained, LAMike being one of them.

I am no engineer and I could be wrong, but I don't think tying a string to the towers and having some buddies push down on one side of the car can replicate the lateral forces of throwing this 2 ton car into a long sweeper at 50 MPH.

There is no right or wrong answer, I say give it a shot if it's in your wheelhouse and your suspension is all sorted out. It's not a big ticket item, for me it was worth the risk/reward.


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...I don't think tying a string to the towers and having some buddies push down on one side of the car can replicate the lateral forces of throwing this 2 ton car into a long sweeper at 50 MPH...

Its the vertical force due to the shift in weight on the bend that is critical, not the lateral... and I reckon with a few strong pals you should be able to depress the front of the car enough.

But be careful... I wouldn't want anyone to injure themselves.

The lateral force you describe from your long sweeper would be applied at the point of contact of the load bearing wheel on the road surface. This force would be applied through the chassis rail via the lower wishbone. This would not directly affect the top of the strut tower. There would be a lateral counter force due to the moment about the lower wishbone joint which is resisted by a reaction at the top of the wheel hub. This would impart a lateral force on the top of the strut tower, but this would be acting in the opposite direction to the centrafugal force on the car, so it would counteract the lateral force at the top of the strut due to the shift in weight.

If you run the suspension on the bump stops (buffers) and you are hitting the road over jumps very hard - I'm talking serious off road action, or 'Bullet' like driving through San Francisco then a strut brace would help to limit the flex in the the strut towers, granted... but the rest of your suspension would get wrecked pretty quickly, and the road would be strewn with parts from you car... fender, sump, license plate...

Regards
Rob

 

I installed the V12 Wiechers solid aluminum bar (a carbon fiber is also offered) and the front end is more composed when driving over uneven pavement. In addition to the Wiechers bar, I would recommend a refresh of the front suspension components.

Although the car is a convertible, I've never experienced cowl shake on this car which puts even more power down than the V8 version.

 

I notice from the photo in the ad that it looks like the strut brace has a hinge at each end. I've always wondered about this, how does fitting 2 hinges on a metal bar aid stiffness?

 

From the pictures of this strut bar installed, it looks like it would take the removal of the retaining bolt on either side, in order for the strut bar to articulate in a vertical arc, about either hinge. I would imagine that the single bolt connection to each strut tower is intended to offer structural rigidity when the bolts at both ends are in place and tightened down, while ensuring that the strut bar can be removed easily when one needs to replace air filters during routine service of the vehicle, for example.

After my usual undecided wavering back and forth, I finally decided to buy this Weichers strut bar, and give it a trial. At the worst I'll be out $150, and at best, I may be glad for the improved handling on rough roads that Richard F and a couple of other satisfied owners of the strut bar noticed after its installation. Over time, I will get to know if there is abnormal suspension component wear associated with the use of this bar, and if that does not occur, I will have a keeper for sure.

To be sure I have a sound suspension to begin with, I am paying even closer attention to all bushings and linkages in the vehicle's suspension system, to ensure any that need replacing are swapped out before the strut bar eventually arrives here in the post.

 

I don't have one.

Just wondering how a bar with a couple of bends in it, then supported by single bolt at each end (even if tight) with no proper triangulation could be very stiff.

I suppose if you had a very stiff bar, any chassis flex could prove problematical. The top mount fixings, are fairly low torque items not designed for lateral stress.

The OEM ones I've seen are solid welded affairs, no hinges in sight.

 

All I know is I like my car on twisty roads better with it on.


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I've considered ordering one but decided against in that its a really simple/inexpensive modification and if it indeed provides benefits then I'm curious why Brabus, Carlsson, Renntech, Koenig, and AMG never utilized one? I've seen them used more extensively with other makes.

 

And yet (for those that have them), the ride is noticeably better.

I find it also helps minimize tramlining on grooved road surfaces.

Glideslope, even though my original front lower control arm bushings didn't appear cracked or worn, they WERE worn out.

 

Have you tried those strong magnets that clamp around the fuel line to the distributor? They claim to improve power and economy. I've heard good results from those that have them! haha :devil

Happy Days! :grin
Rob

 

Who cares if it works. It looks cool!

 

The R129 will never be a corner burner due to it's weight, I think MB and ALL the aftermarket tuners knew this and mostly confined their engineering to straight line acceleration (engine mods) and stopping (braking). RENNtech did offer larger sway bars (I have one of their rear bars) and replacements for all the rear links, but this was most likely to help handle the V12's torque at launch. This may be the reason why there are so few examples of strut tower braces.

Say what you will (even mock the folks that have them), but the ride is improved with the strut brace.

Triangulation would be nice, but I don't really see (on a V12) where there would be room or firm support for an attachment point on the false firewall. There's barely room for the cross bar as it is.

 

R129 is a VERY LOW VOLUME production car, not much of a target for aftermarket stuffs.