Swift is basing it on the stock 14mm bar. JDM, EUDM and AUDM get a 14mm rear sway. When upgrading to 15mm, that's 132%, which is 32% stiffer than original.
From a 15mm to 22mm like the Comptech (assuming similar material and shape), it is 363% stiffer than original or a whopping 463% if using Swift's method of comparing stiffness.

 

assuming one would only have the comptech rsb and supplied bushings as the only mod on the car. would the oem suspension also be a contributing factor to the added stress?

 

Not an expert either, but I've got to think the bushings are seeing decent amount of force. If the end links impart a 'twist' on the bar in a turn where one wheel is 'up' and the other 'down' then some part of that force is going through the bushings. That's why stiffer poly bushings give you a stiffer feel than the rubber bushings. Even though the rubber bushings are pretty stiff, hardly noticeable from the poly when you feel them in your hands.

If you think of the forces of 3,000 pounds changing direction at some speed, even a fraction of that force going through the mount is a lot. And after getting under my car and really looking at these mounts, they don't seem to be built to take much abuse.

I guess I falsely assumed Comptech did their engineering before selling this product. And now that they are going out of business, there is no recourse if something breaks. Is there an A-Spec RSB for the Acura? I've never heard of it so I guess the answer is 'no.' Maybe the weak mounts is the reason.

I'm glad I saved my OEM bar and bushings.

 

Can you look at the mounts and confirm if one is broken? If so which side, drivers or passenger? Also, what RSB and bushings do you have? Do you have any guess of how many miles you put on the bar before the noise started? Of course there will probably be some noise from the stiffer bushings, this may be what you are hearing. This can get worse in cold weather. I'd imagine the noise from the broken mount is much different.

 

i thought the mounts only act as pivot points for the bar to rotate?? Does the bar exert upward/downward force against the bracket/bushing?

Secondly, on some cars like my friends Mustang, the sway bar has NO bushing mounts like us. In fact, it is mounted at two points, of the rear control arm with no "pivot" bushing mounts in the center.

theoretically speaking, if it is exerting force (play), then it is wiser to use softer bushing of course, so that allows the bar to stretch down more without stressing the mount... maybe becuz since the ES bushing is so stiff... there is not enough play for the bar to move, thereby, adding stress to the points.

 

Yeah, this is exactly what I was trying to say earlier b/c that is one of a few differences in the bars that I've seen. Someone once put a stock, Comptech and Progress bar next to each other and I don't recall if there was any other differences.

Either way, it makes me want to switch over to the Progress now.

 

What I did was buy hose clamps and some PVC tube and made my own "locking kit" so that the bar doesn't slide from side to side.

 

Pics please!!!

 

This is certainly not encouraging, especially with Comptech going out of business and therefore of limited help in solving this problem. I have always thought the mounting area for the rear bar is weak. The little bolts are weak and I actually stripped one of the welded-nuts and had to get a longer bolt and put a regular nut on it. I never thought about the additional forces put on the mounting area from a stiffer bar but now that I see the result, it makes perfect sense.

Not much additional strength was engineered into that area, it was made for the 15mm bar and, I fear, not much more. I'll be checking my Comptech mounts frequently and I may just go ahead and put the stock bar back on.

Is there any way that this failure is a product of having the Comptech bar plus other things? Do the guys who had this break have coilovers? Or just the stock dampers/springs? I wonder if a combination of the softer stock dampers with the stiffer bar is putting more of the body-roll resistance on the sway bar (granted, that's it's function) that might be lessened by stiffer dampers.

Or maybe not, that's a question not a statement.

 

I'll crawl underneath tomorrow to take pics if possible. It's 12am here.
It's basically PVC tubing that fits over the RSB. Put 1 piece against each side of the bushing and clamp it down so that there is no more gap and prevents the RSB from moving side to side.

 

As much as I liked the Comptech RSB when I first installed it, I'm now beginning to wish I never had. I've had the clunking for awhile now too. I've just got the original Comptech rubber bushings w/ a little teflon tape and it's been on the car for about a year. It's an 06 MT with otherwise OEM suspension.

I had it into the dealer earlier this week for the infamous '06 seat squeak (fixed) and a shimmy in the front end that was that can only be explained by some kind of ice/snow buildup because it's now gone. While it was there I thought I'd have them look at the RSB/endlinks to get rid of the noise, even if they charged me for it.

They didn't find anything but verified the noise went away when the RSB/endlinks were disconnected. They tightened everything back up. I was initially pumped because the clunk was gone and no charge from the dealer. I ordered a set of greasable ES bushings yesterday and was planning on changing them on a warm weekend.

The clunk is back today, so I was assuming the endlinks loosened up AGAIN. I'll probably try some nylocks to see if I can keep it tight. Anyone know the size of the nut? Now I'll also have to check it for the broken bushing mount.

If I had the OEM bar, I'd probably put it back on. Threw it away last year. I'd also be interested in seeing pics of the hose/clamps for side/side support. And if anyone gets a good preventative weld done, to see pics of that also.

 

I looked at mine this morning, no signs of breaking or stress but that doesn't necessarily mean anything. I'm with you, if I had the old bar I'd put it back on. Now that I know what might happen, I'm going to go around corners gingerly anyway, so what's the point?

The sway bar attachment points are very mild, thin stamped steel and the welds are not robust at all. Funny, I never noticed it before but now that I see the problems people are having, the piece looks very fragile and thin. Especially in contrast to the swaybar and the forces I can imagine get generated at high speeds in turns.

I'm surprised there aren't more reports of these failing under road-racing conditions. Maybe it's a fluke in the ones that have failed? (Wishful thinking?)

 

Check out what JTso wrote over two years ago....

https://acurazine.com/forums/showthr...=neuspeed+sway

"A swaybar with solid endlinks and poly bushings will be more responsive than one with only rubber bushings. Because the full effectiveness of the swaybar won't be realized until all the "gives" is taken away by compressing the rubber bushings. The only concern I have with a thick bar and poly bushings is the D-bushing mounting point. There's a possibility the stress being put on the mounting point during hard cornering can break that part of the mount off. My Neuspeed rear bar for my Civic came with a reinforced backing plate for that same reason"

-JTso

Hindsight I know but it seems this was predicted to happen some time ago.

What about a Neuspeed (19mm) bar with the bushings they use? That might be just within the safe range....

 

I think the "Safe Range" would depend on vehicle, driver, road conditions, and driving conditions. so with those all taken it to account, it would be difficult to determine a "Safe Range".

 

Have we found out if both of these TSX's are 04's?

 

Ya, "safe range" is a bit vague. Everyone pushes their car to different envelopes and has different expectations of what the car should be able to do.

 

Yours sounds like a lack of lube. Teflon tape alone is not enough (I tried that). Best was the thick gray-colored high temperature lithium grease.

 

Hey guys, i want you all to read this. This is exactly what I thought sway bar bushings do. my friends told me the sway bar pushes against the bushing/mount under load. But my assumption was that the whole purpose of the sway bar was to "rotate" or pivot INSIDE the bushings and have nothing to do with pulling or pushing the bushing/bracket upward or downward.

this website also confirms my assumption:

"Q: I have heard that the purpose of stiffer anti-sway bar bushings (Delrin bushings, for example) is to offer less flex, limiting the movement of the anti-sway bar. Is this correct?

A: Not quite. Anti-sway bars, by design, are supposed to counteract body roll during cornering. they do this by mechanically tying the body of the car (in this case the rear suspension crossmember) to the vehicle unsprung mass (suspension). The movement in the suspension during cornering creates a "twist" in the bar. The bar reacts to this "twist" by "pulling down" on the body of the car, resulting in less body roll. The bushings only acts as a link between the bar and the body. The bar, by design, is supposed to twist and rotate in its mounts. In fact, during an impact like a speedbump where both wheels move up and down together (as opposed to during cornering where one wheel moves up as the other moves down), the bar NEEDS to rotate in its bushings or else the suspension movement will be compromised by the binding caused by the interference in the bushings.

Look at a real race car sway bar and you will find that the anti-sway bar is not even mounted in a bushing...they use spherical rod ends as 'bushings' to hold the bar in place in order to REDUCE friction between the bar and the 'bushing'. The only forces which should be impacting wheel motion should be the force generated by the suspension spring as it is compressed, the resistance generated by the damper internals, and the TORSIONAL (twist) resistance of the anti-sway bar – not the friction between the bar and the bushing.

As a general rule, a less compliant (stiffer) material = less bushing deflection = more efficient transfer of forces = sometimes better handling. The bar will still twist the same as it did before and will still "pull down" as much, but if the bushing material deflects under this load it will not transfer the "pulling down" force as quickly or efficiently as a "stiffer" bushing will to the body structure.

In summary, the anti-sway bar determines the total amount of twist. The bushing determines how fast the force is transferred to the body.
"

taken from: http://www.teamscr.com/swaybar.html

so apparently, its POSSIBLE that the only cause of the breakage is caused by when you go over a bump too fast?? and not when your doing extreme hard cornering??

 

Just a few days ago, y'all were posting about what a great mod this is.... now, you're ready to remove it. Not to mention waTSX, who was giving me a hard time for not being a big modder.

Anytime you deviate from the stock parts, you risk getting things out of spec. With no guarantee something won't fail prematurely.

In the meantime, anyone want to figure out what kind of "backing plate" (see JTso's message above) might be made to reinforce the bracket for those who's brackets are not yet broken? Well, assuming that you want to try to keep the RSB.....

I'm also curious to hear more about Aaronng's clamps and how that would prevent failure? Is the bar shifting and THEN causing pressure? I don't get it.

 

Yup, that's probably a big part of it. I'll be shooting lithium grease into the zerks periodically after I get the new bushings installed.

I checked my bushing mounts last night, they looked fine. I'm still concerned though.

The question was asked before, but did the two '04's have any other suspension mods?

 

Entire list of suspension related modifications:
March 04, 2004 @ 5,560 miles - Shop installed Eibach Prokit with stock dampers
March 04, 2004 @ 5,560 miles - Shop installed Ingalls rear camber kit
March 11, 2004 @ 5,915 miles - Self installed Neuspeed upper strut
March 24, 2004 @ 6,275 miles - Self installed Comptech Sway w/rubber busings
Sep 23, 2005 @ 25,112 miles - Self installed ES polyurethane bushings
Dec 03, 2005 @ 27,913 miles - Self installed Cusco Type II
Jan 27, 2006 @ 28, 456 miles - Replaced damaged Cusco Type II
May 27, 2006 @ 33,350 miles - Shop installed Tanabe Sustec Pro OC Type II
Nov 22, 2006 @ 39, 102 miles - Shop installed Rays G-Games 77W 1PC 18"
Feb 21, 2007 @ ~44k miles - Detected broken sway bar mount after clunking noise

 

can we have more information on what happened with the cusco?

 

I hit a rather large rock in some road construction that damaged the Cusco and dented the cat/header. There were some really minor scrapes on the exhaust. It did nothing at the rear of the car.

The damaged Cusco does not relate to the broken sway mount.

 

Any updates on this? I'd like to see what are some DIY options for reinforcing the area.

 

Here is a very simple test you could try. Unfold a paper clip so it looks like a swaybar. Position the horizontal end facing you and the unfolded ends forward. Now move one end up or down, simulating how an independent suspension would move. You will see the twist movement on the horizontal bar and how this movement is translated to up/down movement where the bushing mounting points would be. Stiffer bushings would limit this up/down movement but the energy is transferred to the mounting points. Something has to give.

If you look at the original bushings that came with the Comptech RSB, the top of the bushing is very thin and it is often crushed to a point that causes noises. The replacement bushings have thicker material. This is a good indication how much energy is being moved up or down during the twisting movement of the bar under load.

Btw, there are different methods of swaybar mounting. Independent suspension and solid axle uses different mounting points. A thicker sway is not a problem as long as the mounting points are strong. You will not find the same problem on the front bar because the D bracket and bushings are mounted to a solid subframe, whereas the RSB is mounted to a weak bracket designed for a much smaller bar.

 

are the mounts different on the TL compared with the TSX? are broken endlinks/mounts an issue that TL owners face too?

 

Excellent, excellent example. You can feel the forces at work in your fingers if you use them in lieu of "mounting points" for the paper clip-sway bar. I took two different diameter paper clips (a little one and a pretty good size one) and twisted them both. The difference in force on my "mounting point" is remarkable. This is a good way to understand the increased forces from a 50% thicker swaybar.

JTso, do you have the Comptech bar on your TSX?

 

For everyone following this thread:

We also own a CRV. I have built a pretty good rapport with a SA at one of the local Honda dealerships. Well I stopped in there at lunch today and had chat with this SA about my problem with the sway bar mount.

Long story short.... he introduced me to a Technician in the back who is a Master Welder. I showed this gentleman the pictures from this thread at a PC in the customer waiting area. He said without a doubt he could MIG weld the broken areas; however, he also said something vividly similar to what JTso said with this posting from a long time ago:

"A swaybar with solid endlinks and poly bushings will be more responsive than one with only rubber bushings. Because the full effectiveness of the swaybar won't be realized until all the "gives" is taken away by compressing the rubber bushings. The only concern I have with a thick bar and poly bushings is the D-bushing mounting point. There's a possibility the stress being put on the mounting point during hard cornering can break that part of the mount off. My Neuspeed rear bar for my Civic came with a reinforced backing plate for that same reason"

The Technician also remarked on how puny those stock mounts appeared in the pictures. He said the welded areas would be very strong, and I tend to believe him. He said I could probably keep the Comptech bar but dump the poly bushings but there was no guarantee on anything permanently holding together. His best suggestion was to have something beefier fabricated.

So my end game to this shituation is this.... I am removing the Comptech bar tonight. Then I am going to contact the welder and have the damage MIG welded, hopefully tomorrow or over the weekend. After that is said and done, I am going back to stock.

I have loved the improved handling of said Comptech bar and ES polyurethane bushings but the bottom line, to me at least, is this ordeal was not worth the benefit. My TSX has performed beautifully, and I do not intend to trade anytime soon. The reliability is my goal here. Honestly, I do not think I have pushed the car very hard.

Anyway, I also came to the stark realization that David McDavid Acura in Plano, Texas was 100% useless on this issue. I walked in off the street and got better service at the Honda dealership. Granted, the SA knew me from other appointments, but he seemed intent on getting my problem fixed regardless. Even though this repair is not through the dealership and will be performed at a private residence that is some service IMO. There is light at the end of the tunnel.

 

good to know. hope your TSX fully recovers.

 

I used to have Comptech but switched to Progress due to the clearance problem with my Tanabe exhaust.

 

Although the Progress has the flanges that hold it in place relative to the mounting bracket (side-to-side, I believe), do you expect that bar places basically the same stress on the welded subframe mounting surface as the Comptech bar?

I'm going back to stock -- this kind of ordeal is simply not worth it for a street-driven vehicle. Too bad the mounting points are so wimpy, but that's what they are. JTso, with your welding expertise you could probably weld up a beefier brace. I, on the other hand, can't.

 

No doubt.

 

Whilst I respect JTso's opinion, I have to respect that of the engineer I spoke with from Progress too, but in doing so, there's a conflict.
Given as I've said previously, that Progress used and found 27mm bars (of their design) to be breakers, they've had no issues with their 24mm and 22mm ones.
Also, unless you can test both bars side by side, you can't infer that the Progress bar is as stiff or stiffer than Comptech's.
Wall thickness and where the bends are are additional factors that make up the increase in stiffness over OEM and others'.

I'm going to contact Comptech and see if they can provide me with numbers, and hopefully Progress will be in touch with theirs. Similarly H&R.
Then maybe things will be a bit more clear.

 

No numbers available from H&R, but at 20mm solid bar, and designed for street moreso than track, they are very confident no issues so far will remain no issues attributable to theirs in the future.
Awaiting Comptech's response for numbers.

 

The bar is now off my TSX.

Some more pics:

The driver side mount looks unmolested.


You can see why the loud clunk was persistent. The broken bracket shifted.




Here are some shots of the broken piece.





Notice the "crack" forming in the center. I am not sure, but I "think" this end of the bracket is slightly bent.

 

As long as you're collecting numbers from everyone, don't forget Neuspeed!

Neuspeed's is "only" 19mm. I assume that this, too, would be a "safer" solution, but, as with the others, hard to say for sure without some numbers to back it up.

But still....

 

I've got the pics, but the camera is in the boot! Will get downstairs in an hour or two when the boss isn't looking. The only way to reinforce the area is to weld a reinforment plate to it.

 

Done - Whiteline to go, unless Aaron fancies doing that one for us?

 

I'm not sure how a reinforcing plate is going to transfer load from the points where the mount failed. The flat part of the bracket is not the weak link, it's the puny fingers that are spot welded on the sides of the mount and the other vertical surface where it fails. If anything, a stiffer flat part of the bracket will transfer these loads more efficiently and actually increase the loads on the part of the bracket that is failing. I suspect the crack on the flat part of the bracket shown earlier was a secondary effect of the failed bracket twisting under load. You would have to weld in reinforcement on the sides of the bracket to make a difference.

What is confusing is how one bracket can completely fail yet the other side appears undamaged. It could be the drivers side is a little different, enough to be able to handle the loads that the passenger side can't. Puzzling.

 

Good luck, I suspect their engineers were the first employees to be let go.