Car is 97 Integra GSR
Spring are 10" 425 lbs/in.

I took one of my front Bilsteins off for some maintenance, and noticed that the shock shaft had light scratches on one side. Upon further inspection, one side of the rod guide had worn out. It turns out that the uneven loading of the spring causes some pretty significant side loads.

Here's a picture of the shock assembly installed WITHOUT the top hat bushings, just to see how much side loading there was in the shaft.



It's hard for me to tell how much force it takes to center the shaft. Maybe 5-10 lbs or so? I can center the shaft by pulling on it with one finger, but it feels pretty significant. Like you wouldn't want your shock to experience this.

The problem is probably due to the uneven loading of the spring as the suspension travels thru it's arc. I'm currently trying to shim the upper spring mount a bit to try to get the shaft centered at ride height. Upon compression of the spring, the side load changes direction slightly.

Any other suggestions for how to address this problem, short of buying the Hyperco hydraulic perches?

By the way, my Koni's had no such problems on the shaft, so I assume that they had better rod guides.

 

I was looking at Dennis Grant's Suspension page and he suggested something called "torrington bearings". The closest thing I could find on McMaster was a needle bearing assembly part #5909K42.

Specs:
OD: 2 1/2"
ID: 1 3/4"
Dynamic Thrust Load: 5600 lbs
Assembly Thickness: 5/64"

 

What springs were you running on the Konis? It could very well be that your rather tall springs are causing that off-center load.

 

The Torrington bearings only have a rotational degree of freedom, which is good for adjusting the collars if the spring is preloaded. It doesn't allow any tilt. However, there might be other spring complexities, in which twist is converted to side loads, I dunno.

The springs I am running now are the same that I used on the Konis a little while ago. I think a longer spring might have less side loading, since it is easier to "bend". I'm not sure, though. I can't run any shorter than 10" due to coil bind issues.

 

Not to bring that up again, but I still don't see why. Hundreds, if not thousands of Integras are running 380-400 lb/in 8" front ERS springs without issue. I did not have issue with mine.

I read your OP again, and I'm kind of unclear and what part had wear on it? Why would the upper mount bushings not keep it centered? I would guess that it being off-center like that is just due to the angle of the spring/damper assembly with respect to vertical/horizontal in a vertical plane drawn between the left and right wheel hub centers.

If you raise the car off the ground (before you reach full extension and the shock rod starts to fall out of the top mount), does the top of the piston change its location at all, relative to being centered?

 

As the spring compresses, I believe the natural tendenacy is to twist. If the spring can't twist since there's too much friction on the spring surfaces (GC spring perch and rubber isolator), then the side loads are generated. If the spring can spin by using the bearings, then the side load is reduced. It's not as good as the Hypercoil's which allow tilt but it's a heck of alot cheaper and may be enought to reduce the issues you're having. At least that's the impression I got from reading Grant's article.

FYI the Hypercoil perches have to be rebuilt periodically. According to Hypercoil's website, they say every 10-12 hours of cycle time which I'm guessing means use.

 

Yeah those Hypercoil mounts are totally NOT for street use. I'm pretty sure they're supposed to be rebuilt every 10-12 hours of track use. So if you use them on a track car that sees road racing for 2 hours at time, you'd need to rebuild them after every 5 or 6 events.

For the street, you'd have to rebuild them once or twice a week!!

 

Its not just his 10" springs causing the issue. My 8" front springs rub the GC threaded sleeve, to the point where some of the threads are now useless/missing. Of course, those threads are higher up on the sleeve than I could ever get the perch (without massive preload and a 4x4 ride height), but it is somewhat alarming to see the mashed/rubbed down threads...

 

what the hell? I mean I only had my GC's for about 10 months, but I know for sure the spring coils never touched the sleeve threads.

 

I do believe that you've posted that you've never had your UCA hit the shock tower. Mine have, repeatedly enough to leave dents. Perhaps you simply never had the suspension compressed during use as far as I have.

Setup is OTS Koni Sports, GC sleeves, 400/400 rates (Eibach springs from GC, 8"/7"), and GC extended upper mounts. Maybe the upper mounts and GC supplied bumpstops allow more bump travel than they should?

 

my shock tower is tower from my passenger upper control arm hitting in during aggressive driving.

 

I based my decision on some "math" I ran, which I explained in that other thread. I think we came to the conclusion that nobody else has problems because they have no suspension travel left.

The rod guide bushing

They do, but it also means that they are exerting force on the shaft when they do so.

yes, it moves around a bit

I might try the torrington bearing idea, since they don't cost a lot. Right now, I just shimmed in a piece of rubber underneath the spring upper perch, and it seems to have made the side load "less bad" at ride height.

 

You mean the metal sleeve that fits through the upper mount bushings?

I wonder if this is something stock suspension, or stock-style suspension would exhibit, i.e. if I removed those top bushings like you did, but using my stock front springs on Koni shocks, if they would be off-center like that. If so, I would think it's something that Honda would have taken into account.

I never noticed anything out of the ordinary on my upper mount bushing metal sleeves when I had them apart after removing my H&R springs to install GC's, or when I removed the GC's and put my stock springs back on.

 

No, I mean the bushing right under the top seal of the shock. It keeps the shaft aligned.

 

I think you're a bit too concerned with this.

 

When the shock shaft develops scratches, and the Teflon on the bushing has worn away, resulting in the shaft rubbing against metal, then yes, I worry.

 

Oh, you're talking about something inside the actual shock body?

 

Just thinking at the most simple angle. Possibly you preloaded the fork my tightening your fork to LCA bolt while the car was raised? This would give the side load you are seeing.

?????????

 

He means along the shaft, to which the piston is attached. The guide that the shaft travels along is typically teflon. The guide is inside the upper cap, which seals the shock body.

OP - I'd be concerned if I was you as well, but I don't think the torrington bearings are your answer. Look at OEM springs and other springs with open ends, that sit in a notched spring perch. There is not much allowance in that design for twist during spring travel.

I think the issue is with the guide itself - was it simply one of a bad batch? What is happening at the other side?

 

The shaft for the other shock also has some light scratches, but maybe not as much. I don't think there is anything defective about the rod guide - only that Bilstein did not spec a beefy enough one for OEM applications. It is the same top cap and rod guide as used on their circle track shocks, which are meant for double eyelet application.

In any case, the rod guide is a dinky little 1/2" tall metal cylinder with a thin and flaky layer of Teflon on it. I don't think it is that durable against side loads. Do you know where I could buy a more durable insert?

 

I tried installing the shock without a spring, and the lower bushing only creates very small side loads.

 

You need to fabricate a set of spring perches to keep the springs co-axial to the shock. As DG states, "any bending moment on the shock rod and spring that occurs when the spring seat doesn't pivot coaxial to the shock rod wears out seals in a hurry, can bend the shock rod, and worst of all, does all kinds of funky things to the spring rates, as the spring is no longer compressed evenly throughout the shock stroke. It is really, really worth the effort to ensure the spring is always compressed squarely."

DG offered up schematics of a coaxial spring perch for a DSM here. With your fabrication skills as evident in the DIY shock dyno thread, I'd bet you can come up with a similar design for your Integra using the above plans as a basis.

 

I don't, sorry. But it seems strange that this is only happening on one side... all this talk about torrington bearings and hydraulic spring perches seems to be covering up a deeper issue. What does Bilstein have to say about the situation?

 

I don't really see any plausible solutions to this other than using the Hyperco perches or converting the suspension to a custom cantilever or bell-crank operated mechanism and reloating the coilover assembly elsewhere. There is just no way to compress the spring squarely by leaving the coilover assembly located where it is - at least not without using a shorter spring and/or reducing damper compression travel.

While it is mostly true, I have to disagree with Grant on that one (mainly with his inclusion of the word "any"), as the OE Showa dampers on double-wishbone Hondas have been known to go hundreds of thousands of miles without developing leaky seals. Now, when you eliminate any compliance in the upper mount by removing the spring isolator and using a spherical bearing, I can see where that could contribute to the problem . . .

I would imagine it can pose more of an issue with Mac strut cars or DW cars that have odd damper geometry (what is the geometry like on a 2nd-gen DSM?), but I'm kind of skeptical of the side loads being generated by a DW Civic or Integra. I'd like to see some figures on this out of curiosity.

 

Thanks for the link. I think his design won't work so well for us because it significantly limits the compression travel available. For one degree of tilt, I could just make a plate that pivots on two points, but I haven't come up with a simple way to have two degrees of tilt, save using an "angular contact spherical plain bearing", which costs like $200.

I haven't checked the rod guide on the other side, but I would expect it to be in similar condition. Bilstein wasn't all that helpful on the issue. The North Carolina guy basically said to run it until things start leaking (no way...) and the California guy kept saying that I should send it back for a rebuild (no way...).

It would vary a lot based on configuration. I would guess that TunerNoob has it pretty bad. Why don't you try removing the top hat bushings and see for yourself next time you plan to take the damper out?

For now, I just wedged in a piece of rubber underneath the upper spring mounting bushing, and that made the problem "less bad".