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      04-04-2009, 09:18 PM   #45
swamp2
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Quote:
Originally Posted by kmarei View Post
why don't we ask the manufacturer for the testing data they got when they tested at nurburgring?
i am sure they drove a regular M3 and an M3 with the bar installed?
i am sure they kept record of all the times they did
or they just threw away all this money
but in all honesty
this strut bar does look very flimsy
the thickness of the 2 solid points on either side looks very weak
and all this presure its being subjected to is only being help together by the 2 bolts?


i have used a front strut brace before
and it made a huge difference
but my car was a convertible so might not be the same case
but i doubt the effectiveness for the rear since that's an enclosed space
meaning the rear metal parcel shelf adds ridgity already
whereas the front strut brace is the only solid thing between the 2 strut towers
since hood doesn't add any ridgity
Many good points here. Totally agree.

However, even if they did test at the Ring. It does not save Mr. Vendor from being wrong about researched AND developed at the Ring...
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      04-05-2009, 10:56 AM   #46
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Official reply from ACS Germany.

Hello board members,

It is the weekend, and I am waiting for the information I have requested from ACS Germany. I should be able to supply all of the info by Monday.

As for you Swamp,

I officially retract this statement:

"(I have read some of your posts and I know you are educated in vehicle tuning as well ) So peer to peer."

It is very evident that you make posts to get a rise out of people. I will not feed into your childish games. Below is my final words to you:

Statements like: "might get ugly", "99.9% sure","knowledge of manufacturing is nearly nil", "Put up or shut up, really", "I would bet pinks on this.", "I would be willing to bet it was not researched and developed (R&D) AND tested at the Ring."

You make all of these statements on a guess. You have never seen this bar in person. You have never driven a vehicle with this product installed. You have never been to ACS Germany and know nothing about the company nor their research and development process. Yet you are 99.9% certain about the materials and testing used to manufacture this product.

Even when Blake chimes in and reenforces my experience with the product you feel that you have a better understanding of the product than he does. So who's credibility is in question now?

It's members like you that make manufactures reps like myself not want to be on these forums. I only contribute to this community because I myself am an enthusiast (with an E92 M3), and have the access to information that is not readily available to all members.

I would like to say that I have nothing against this forum, but "members who have little knowledge of what they [post and provide such false information on a guess] - that is another story."

Members, stay tuned for the official statement from ACS Germany.
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      04-05-2009, 02:28 PM   #47
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Quote:
Originally Posted by Frank@CEC View Post
Statements like: "might get ugly", "99.9% sure","knowledge of manufacturing is nearly nil", "Put up or shut up, really", "I would bet pinks on this.", "I would be willing to bet it was not researched and developed (R&D) AND tested at the Ring."

You make all of these statements on a guess. You have never seen this bar in person. You have never driven a vehicle with this product installed. You have never been to ACS Germany and know nothing about the company nor their research and development process. Yet you are 99.9% certain about the materials and testing used to manufacture this product.
Might get ugly because your lack of knowledge is embarrassing, that is all I meant. Perhaps you could enlighten us on your extensive manufacturing or engineering experience? I'd be happy to do so for mine.

^ all pretty irrelevant. The thing about engineering, manufacturing and product design experience is you don't have to see something in person to make very solid, educated guesses about it. With the proper experience such things become obvious. I never said I drove a car with it, but again that is fairly irrelevant toward my claims. Most of my claims are indeed educated guesses, but ones I am clearly confident enough in to lay them on the table in this fairly firm manner.

Not to digress too much into theory or epistemology, but since I have not spoken directly with the ACS engineers I could not have facts with 100% certainly. But if you want to truly nitpick on certainty, deception by them or deception by a supplier is also a very remote but finite possibility as well. The business of absolute certainty is indeed rare. Hence some of the qualifications I provided.

Quote:
Originally Posted by Frank@CEC View Post
Even when Blake chimes in and reenforces my experience with the product you feel that you have a better understanding of the product than he does. So who's credibility is in question now?
It does not take many brains to understand that there are technical aspects of products and experiential ones. Unfortunately, one gives much more insight into the other than conversely.

Quote:
Originally Posted by Frank@CEC View Post
It's members like you that make manufactures reps like myself not want to be on these forums. I only contribute to this community because I myself am an enthusiast (with an E92 M3), and have the access to information that is not readily available to all members.

I would like to say that I have nothing against this forum, but "members who have little knowledge of what they [post and provide such false information on a guess] - that is another story."

Members, stay tuned for the official statement from ACS Germany.

Wow, talk about the pot calling the kettle black. It is nice to see that you have contacted the manufacturer directly. Perhaps you should have done so BEFORE you rattled off the former list of drivel? This simply continues to demonstrates your lack of credibility. If you had such intimate knowledge of the product already why do you now need to contact the manufacturer?


My reputation here as knowledgeable, firm but fair and a solid contributor will stand the test of your frail little criticisms. I have had plenty of nice and positive things to say about other vendors and other products.

Quote:
Originally Posted by Frank@CEC View Post
Below is my final words to you:
Apparently not since the information from ACS will be "to me" as well...
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      04-05-2009, 02:48 PM   #48
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Looks good though Frank - can you pls PM me with price? Thanks.
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      04-05-2009, 11:37 PM   #49
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Question

You happen to have any installation photos?
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      04-08-2009, 12:02 AM   #50
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Quote:
Originally Posted by Frank@CEC View Post
It is the weekend, and I am waiting for the information I have requested from ACS Germany. I should be able to supply all of the info by Monday.


Two obvious conclusions...

1. You have a great inside line with ACS to get important information quickly.
2. Setting the story straight is a high priority for you.

yawn...
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      04-10-2009, 11:17 PM   #51
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swamp2 1, Frank@CEC 0.

Your hollow indignance is duly noted. Either you can't get the truth, it was not what you wanted to hear or you just don't care about your credibility. In any of these cases simply see the first line above.

Case closed.
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      04-10-2009, 11:56 PM   #52
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Quote:
Originally Posted by swamp2 View Post
swamp2 1, Frank@CEC 0.

Your hollow indignance is duly noted. Either you can't get the truth, it was not what you wanted to hear or you just don't care about your credibility. In any of these cases simply see the first line above.

Case closed.
+1...

I agree...
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      04-11-2009, 07:07 PM   #53
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Thumbs up ACS rear strut brace

Hello board,

Excuse the delay, as I am on vacation and just got the information from remote.

ACS's official statement regarding the materials and manufacturing of the rear strut brace is the following:

"the bar is made of simple aluminum, billet and anodized."

I will retract the "hard" anodized statement as they did not clarify if it is indeed "hard" anodized, but did state that it is anodized.

Now since there is question about the function of this unit, I had ACS Germany airship me a strut brace for my car. Good news is I JUST GOT IT!

I have attached some pictures of the unit and will explain the function of it's design for the members who care to listen. Some members have questioned the design without ALL of the information, and a lack of detailed pics. You know what they say about those who assume...

The brackets on each corner have four fixing locations, two on the top of the strut tower, and two on the side. This helps with vertical movement. The bolts that hold the bar to the bracket were designed as a quick disconnect feature which allows removal of the bar without removing all of the interior carpeting. Very cool feature IMO. These are not "mechanical pivots" as one member said. The "shelf design" of the brackets does not allow the bar to pivot, thus eliminating vertical movement and body roll.

I will be on vacation all of next week, so I have decided to give our tech a break and do a DIY on this strut brace.

I will take detail pictures of the install... stay tuned for DIY and driving reviews.
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      04-11-2009, 07:32 PM   #54
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Frank, Interested to see your pics and hear your review. Good work contacting AC about the product. But I can tell you it's clearly not billet aluminum. Billet simply means it was machined into the shape it's in. That is simply square stock aluminum. Nothing wrong with it. In fact that would be better than billet since it would be pointless, costly, and wasteful to make that piece billet aluminum when square (or tube) stock is readily available. The brackets on the end aren't billet either. They are two pieces of flat stock cut, bent and welded together.
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      04-11-2009, 08:12 PM   #55
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still don't get how the 2 screws on either side are not a mechanical pivot
if the screws are not tightened all the way
is there any movement between the strut bad and the mounting bracket?
all the pressure from the strut towers is being held by those 2 small screws
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      04-11-2009, 10:11 PM   #56
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Maybe there should be two sets of bolts on each side instead of one. In the original pictures by the OP, it looks like his bar is pivoting on the passenger's side as the bar is not completely parallel or resting on the "shelf".
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      04-11-2009, 11:35 PM   #57
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[quote=J08M3;4897947]Frank, Interested to see your pics and hear your review. Good work contacting AC about the product. But I can tell you it's clearly not billet aluminum.

+1 on the not billet point. I noticed this once I received my bar. It's not solid. Yet ACS still said it was billet. But they might be confused because other braces, like the front strut brace they make for the E60 M5, are billet aluminum.

http://www.cecwheels.com/tunerproduc...3/5SeriesM5E60

Last edited by Frank@CEC; 04-11-2009 at 11:57 PM. Reason: spelling
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      04-11-2009, 11:51 PM   #58
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Quote:
Originally Posted by rbk1115 View Post
Maybe there should be two sets of bolts on each side instead of one. In the original pictures by the OP, it looks like his bar is pivoting on the passenger's side as the bar is not completely parallel or resting on the "shelf".
Correct. This is due to misalignment. In the instruction manual, ACS state that a rubber mallet should be used to tap the brackets into place once the brackets have been bolted to the strut towers. Once aligned properly, the bar will sit flush on the shelf.

I started installing the bar late tonight, but have put it on hold until Monday. The bar is bolted in, and aligned, just need to reinstall the carpets and make the cut out. I'll post all the pics once I'm fully finished.
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      04-12-2009, 03:52 AM   #59
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Quote:
Originally Posted by Frank@CEC View Post
Correct. This is due to misalignment. In the instruction manual, ACS state that a rubber mallet should be used to tap the brackets into place once the brackets have been bolted to the strut towers. Once aligned properly, the bar will sit flush on the shelf.
that will be fixed monday. thanks for pointing that out!
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      04-12-2009, 04:04 AM   #60
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So just as I claimed before:
  • The bar is not hard anodized.
  • The bar is not made from billet.
  • The center bar is not machined (unless you count a cut off saw or the machining in of the AC logo as "machining" ).
  • The bar will not improve "roll stiffness" as claimed.
  • The bar was most likely not R&D-ed at the N'Ring.

To top that off I have a new claim:
Quote:
Originally Posted by Frank@CEC View Post
The "shelf design" of the brackets does not allow the bar to pivot, thus eliminating vertical movement and body roll.
  • The bar absolutely will not eliminate vertical movement. At best it will slightly improve RELATIVE vertical movement of the strut towers (until the part begins to yield as I explain further below). What utter rubbish. AC should really be embarrassed by such nonsense from their reseller. Words have a precise meaning and need to be chosen accordingly.

However, to ACs credit the design is ever so slightly better than a true freely pivoting design, but not much better because:
  1. As you can see in the OPs pics any slight deviation from one car to another will have enough misalignment that the constrained pivot actually turns into a true pivot, just as I stated originally. Do I understand the instructions correctly that you are supposed to work around this by getting the end brackets above their yield strength by bending them into position with a mallet? It keeps getting better
  2. The design requires a precise zero tolerance fit of the bolts. Excessive contact stress at the bolt holes and between the shelf and bar will cause local yielding stresses which will increase slop in the fit and again make this a true pivot.
These are basically an expansion of exactly what kmarei said above....


In conclusion:
  1. This is a massively over priced part, that is expensive for reasons of gross profit instead of the reasons claimed by Frank. Note this vendor (not CEC) is asking $750+ for this very bar (link). These bars can be made for ~$50 in quantity. That price is really distgusting. Heck I would even get into this business at those margins but I would be embarrassed to offer such a shoddy design at $300 let alone at $750.
  2. It is a fundamentally flawed design with a constrained pivot (soon after any hard use becoming a true pivot).
  3. This design absolutely will not function in the way claimed by Frank - improving roll stiffness and eliminating vertical movement.



Keep it up Frank... Get your shovel ready... I am really looking forward to a wonderful drive report of how much better the car FEELS once you get this part mounted up in your car.
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      04-12-2009, 04:16 AM   #61
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OMG it gets even better... CEC will charge you $580 for this part for your 335i and $776 for the EXACT same part for your M3.

Price lists are attached (freely available on the web). Part number is 3334-90-310.

And everyone wonders why aftermarket M3 parts are so damn expensive. The low volume argument just does not hold up here. Sure the parts are low volume (for both cars) but still are IDENTICAL. This is clearly the "screw the enthusiast for every penny we can get" factor.

Let me guess the part for the M3 is a higher grade of aluminum, uses titanium fasteners, is dye penetration and x-ray inspected, was developed by an ex DLR scientist and will get you around the Ring 20 seconds faster.
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      04-12-2009, 07:27 AM   #62
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still waiting for the nurburgring times, if they exist

swamp2:
so when will you start selling these for $50
i wonder if you can make the same dsign without the brackets and screws etc
just one solid piece
now THAT would work
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      04-12-2009, 10:39 AM   #63
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Quote:
Originally Posted by kmarei View Post
i wonder if you can make the same dsign without the brackets and screws etc
just one solid piece
now THAT would work
That is actually the main issue here. People want performance, but do not want to compromise usability. Then vendors claim they have products which deliver the best of both worlds without compromises. (I am not sure what CEC claims regarding this issue. That is not clear based on what has been posted here so far. They clearly claim "a" performance benefit, but I am not sure if they claim their design is as rigid as a solid bar or not.)

If you have a few free hours in your hands, and have access to a basic shop, you can build a solid bar by spending ~$50 as Swamp says, but nailing down the necessary dimensions and tolerances would take time. Then there is the issue of how necessary that is to begin with since this part of the chassis is fairly well reinforced (as compared to the front suspenion mounts for instance). I am sure there is still some minor relative motion, but the question is would your average enthusiast actually benefit from establishing a more rigid connection between the rear struts or not. My guess is no.

From the more detailed pics, it is clear that the pivot appears to be somewhat constrained for rotation in one direction, and much less so in the other rotational direction. The contact between the middle bar and the sleeve to each side of the screw will impede rotation somewhat. However, there are two core issues with that design which Swamp already identified: you need a zero tolerance on the bolt for there to be absolutely no play from the very beginning before any loading (which is not possible, and one of the pictures clearly show how much slop there is); if there was indeed significant vertical relative motion in the suspension mounts, then the bar would experience significant loading and the bolt might yield the Al bar or the sleeve at the contact surfaces (that one cannot know for sure without doing some analysis).

The pricing does seem to be high indeed. Dinan sells very similar parts (materials, processes, etc) for M cars for ~$350, so clearly the margin on this particular product is very high. Then it is up to the consumer to decide if they want to pay for that margin or not. I personally wouldn't, and if I felt like I would benefit from a more rigid connection between the rear towers, I would build a solid piece myself.
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      04-12-2009, 12:22 PM   #64
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Swamp2, Lucid,
Why are you even contributing to this thread. There is rarely any benefit to these bars (either front or rear). Anyone with any common sense knows this. Let the lemmings fall off the cliff.

Create a force diagram for the front or rear suspension and note where and in what direction the actual forces act. Then calculate the contribution of a solid bar (give the vendors the benefit of the doubt) and note that the bar cannot contribute any meaningful resistance in the directions of interest.

For all of the cheerleaders out there promoting these stupid things, please answer me this question: Is a strut bar loaded in compression or tension when a car is cornering at the limit?

And one final comment: I find it amazing that people will actually claim that these things actually cause the car to corner flatter! If you believe that, I have some cream that is guaranteed to make your penis bigger if you rub it on.
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      04-12-2009, 01:01 PM   #65
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It would be nice if the "Name Brand" aftermarket tuners could design bars like these and sell them at reasonable prices. Expensive "engine bay & trunk candy" is not my thing. These bars were on my old E36 M3 and were designed by a company called JT Designs here in So Cal. The guy was local to me and even installed them on my car for me. Sorry for the bad pics of the rear bar, but you can kind of see it at the top of the picture. This guy really thought about the design and everything. They are a solid piece design and the rear bar is just as easily removable, if not easier than what ACS came up with. However, these bars were not R&D-ed at the N'Ring.

http://www.jt-designs.com/

Look under "BMW Products" and then under "Suspension Components and Systems".
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      04-12-2009, 01:08 PM   #66
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Quote:
Originally Posted by Radiation Joe View Post
For all of the cheerleaders out there promoting these stupid things, please answer me this question: Is a strut bar loaded in compression or tension when a car is cornering at the limit?

If you believe that, I have some cream that is guaranteed to make your penis bigger if you rub it on.
well with this bar probably neither compression nor tension
cuz it will be too busy moving on the pivot point around the side mounted screw

PM about that cream
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