[benton0311]

I purchased a lightly used set of KMAC Stage 2 camber plates several years ago and I'm finally getting round to installing them. I've got them mounted on Koni Yellows, Tein springs with E30 "lift" upper spring plates and all new rubber insulators.

The problem: Once the top nut is fully tightened down on the top of the strut, the strut will no longer turn inside of the plate/spherical bearing due to the clamping pressure from the top nut on top of the spherical bearing. I haven't tried installing them on the car yet since I cannot get the strut to turn as it should inside the camber plate.

Has anyone else experienced this with camber plates before? I've installed camber plates on other cars and never had this issue but it was on coilovers so I was able to remove preload from the spring to reduce pressure on the plate.

I spoke with KMAC about this and they are unsure of what could be causing it. I used wheel bearing grease inside the spherical bearing/outside top nut but was assured by KMAC that this wasn't required due to teflon coating inside the spherical bearing. The spacer is being used below the bottom conical washer so there is no binding against the upper spring plate. The problem appears to be that the top nut is forcing down on the spherical bearing and against the bottom washer creating so much friction that it won't turn. Would this possibly be relieved when everything is installed on the car and the weight pushing downward relieved tension on the top nut?

Also, I noticed that the top nut does not contact the top of the conical washer inside the spherical bearing. It seems to me that it should so that pressure is held by the inside shaft of the top nut against the conical washer. It almost appears that the conical washer or top nut shaft is 2 mm too short.

[benton0311]

Is the gap between the top nut shaft and conical washer shaft, which it would appear should join together to form a solid, rotating shaft inside the spherical bearing, correct?

[serotoninsteve]

Problem is that they don't use an axial bearing to allow the lower assembly to turn against the camber plate.
As now the spherical would need to turn but is to tight to allow this.
In your design it would need a bearing between the conical washer and the spacer.

Possibility 1 would be to not use these camber plates as they are a poor design.
Possibilty 2 is what I have used on a race car where we had the same problem is to use one of these:
http://www.summitracing.com/int/part...b250/overview/

Their purpose isn't really what they need to achieve here but it works for me.
Just put some marine grease on them and they can do their thing between the spring and the perch.
The other circular movement is done inside the strut itself.

[benton0311]

Thanks so much for the reply. I think at this point I'm leaning towards Possibility 1 and just not using them.

The problem I see with the axial bearing solution in this case is that it would still have pressure from the top nut forcing down on the spherical bearing even with the bearing on the bottom. So it would appear that I'd need two per strut, one bottom and one top or that the real solution would be the correct length top nut and an axial bearing on the bottom.

I almost think that they sent the wrong top nut kit with these plates (should be 2mm longer) or they switched to a thicker spherical bearing during production without changing the length of the top nut shaft.

[ajsalida]

I don't think the strut shaft is supposed to be able to turn freely inside the spherical bearing, while the bearing does not move at all. The spherical bearing is supposed to be able to rotate back and forth a little inside the mount, and tilt a little bit out of vertical. In order to do that maybe KMAC has designed the top nut and conical washer to clamp the spherical bearing, I don't know.

Generally spherical bearings aren't supposed to take big axial loads. But that never stopped camber plate makers from using them. They are supposed to be used like on sway bar links or other links that deflect/rotate.

edit: I would contact KMAC and ask about that gap, if it supposed to be there or not, and if when assembled the shaft is supposed to turn freely...

[vwetish]

I think that the conical washer or the spacer is binding with the stationary part of the bearing not allowing the rotational inner part to turn together with the strut shaft and the spring perch. I will look into that. If not might be over tighten.
Also, actual photos would help determine the problem.

[benton0311]

Here are some pics of the plates, bearings, etc.:

Assembled camber plate showing spring plate, spacer, and conical washer:


Top nut/assembled plate:


Top nut and conical washer assembled on strut without the camber plate and spherical bearing. Fits perfect without the plate and this is how I think it should look when assembled in the spherical bearing:


This is how it would look when it is assembled inside the spherical bearing due to the top nut being too short (I think) - note the gap:


Top nut and conical washer inserted into spherical bearing, note the ~ 2mm gap at the bottom of the top nut thread between the top nut and conical washer:


Spherical bearing inside bushing - I think this bearing is either too tall or the top nut too short:



I could be wrong but it definitely seem like the gap is causing the problem with sandwiching the spherical bearing with too much pressure. As someone mentioned, perhaps it was designed this way for some reason but the strut will not turn if the top nut is tightened. If the top nut is loosened then it just spins off the thread when the strut moves and as soon as it's tightened a little or a lot the strut no longer turns.

[benton0311]

This is what I received from KMAC:

"..Presume you are using OEM diameter springs with the stock OEM top spring seat (not smaller diameter coil overs).

Once the whole assembly is tightened (we supply 3 pairs of nuts – as aftermarket Koni, Bilstein etc sometimes use different diameter strut shaft threads than the OEM 14 x 1.5 thread pitch).

The strut shaft nut needs to be tightened by an impact gun to assure fully tight.

The center self aligning spherical bearing is Teflon lined so does not need lubrication (they are tight but this is required to prevent premature pounding out) – encasing in urethane cushions the bearing, greatly extending wear life and is therefore often chosen for rally and off road.

When you say “spin” keep in mind this bearing is a vertical load, not a high speed design bearing.

Being Teflon lined the only thing that could prevent turning would be if the spring seat top surface was binding against (the stationery) underside of the blue clamp plate.

But with the alloy spacer and cone shape washer between top of seat and underside of bearing (as you describe) you should observe clearance/no binding!

Hope this information helps...."

[ajsalida]

I think they are saying the bearing is only supposed to turn inside the camber plate, and it will feel very stiff. I'd be surprised if you could turn it by hand.

I do not think the shaft is supposed to turn inside the bearing, let alone spin, even a tiny bit of play in there would eventually pound the sh*t out of that, as they said, it takes a vertical load.

One thing you could do is assemble & install it, drop the car down onto it and see if there is any binding in the steering lock to lock.

[Cloud9blue]

I would say just call your lose and go with a different kit, preferably one with a proper radial bearing to take the spring load, such as Vorshlag or Ground Control ones.

The problem will only get worse if you several hundred pounds of pressure on those washer and the bearing once you get it installed on the car. And without a radial bearing to take the rotational movement, that spherical bearing will wear out very quickly. There is a reason why you don't see KMAC selling a lot of those plates.

[benton0311]

Thanks for the input everyone. Part of me wants to install everything and drop it down to see if the wheel turns ok while loaded but I'm probably going to cast these aside and throw the stock mounts on for the time being. If I can't turn the strut in the plate then I'll have a hard time even getting the studs to line up in the strut tower when mounting. Maybe I'll look at Ground Control down the road, I ran those on my STi and they were great.

I'm kinda bummed, I was really looking forward to some extra caster to improve the poor on-center feel of the steering.

[Cloud9blue]

Originally Posted by benton0311

Thanks for the input everyone. Part of me wants to install everything and drop it down to see if the wheel turns ok while loaded but I'm probably going to cast these aside and throw the stock mounts on for the time being. If I can't turn the strut in the plate then I'll have a hard time even getting the studs to line up in the strut tower when mounting. Maybe I'll look at Ground Control down the road, I ran those on my STi and they were great.

I'm kinda bummed, I was really looking forward to some extra caster to improve the poor on-center feel of the steering.

Extra caster won't help a whole lot for our cars I would imagine. Since the stock caster angles are already pretty ample at +6-7 degree if I remember correctly. Look into M3 front control arms and wider tires if you want better steering feel.

[vwetish]

After seeing the photos, and due to the plates design I don't think the gap is the problem since this works just as stock strut mount. I think is the conical washer on the bottom that is causing the binding. When is tight is catching on the stationary outside portion of the bearing not allowing it to turn. The shaft turns together with the washer, the strut perch and the strut body itself. Since is of the car I assume you can see the marks from the metal to metal contact. You can even spray paint, install, tighten loosely and turn so it will leave marks. Also, is possible that that spacer need to go between the bearing and the plate and not on the spring perch. Usually the conical washer sits on the perch. I definitely one of these things and not the gap.

[serotoninsteve]

I don't see the sense for the conical washer at the position you put it.
Has the sperical bearing a conical shape at its lower side to fit the conical washer?
Fact is that the sperical bearing must be squeezed to form a fixed unit together with the strut shaft and upper spring perch.
The gap you think is to much is necessary to allow the squeezing.

Would it still get squeezed without the conical washer?

If everything is tightly squeezed together and the sherical bearing sits tight you wont turn it by hand.

One time in the car your steering input will turn the strut and the spring needs to transfer the turning force to the upper part and turn the tight sherical bearing.
Mostly this doesn't work and the spring makes funny klingklong sounds while turning, or worse the upper strut nut can become loose.

That's why all the good camber plates (KW, Vorshlag, GC, TCKline, ...) use a ball bearing somewhere to allow a stressfree circular movement.

[benton0311]

Seratoninsteve, the top of the conical washer is actually a cylinder that matches the top nut shaft and fits into bottom of the spherical bearing (I think conical washer is somewhat of a misnomer but that was the nomenclature used). It basically has a short shaft that fits into the bearing with tapered sides at the bottom. It's in the correct position according to KMAC and the bottom of the spherical bearing would wobble on the strut shaft without it. You can see it pretty good in the third photo.

Knowing that the shaft formed by the top nut/conical washer shaft is not supposed to turn answers some of my questions. I didn't think it would be feasible to rotate the spherical bearing which is why I thought the shaft formed by the top nut and "conical" washer were supposed to turn inside of the spherical bearing.

The bearing/bushing assembly is threaded into the upper part of the camber plate to facilitate replacement when worn out. You can see the bearing assembly just below the lower blue camber plate in the first photo. When loosened, this threaded portion turns quite easily in the threads, so easily that I first thought it was a separate radial bearing assembly until I dissassembled and unthreaded it from the camber plate. I though about loosening the whole assembly so it can turn but I'm not sure if constantly turning a threaded assembly would be practical in the long run.

[ajsalida]

You may want to try the following before you give up on what I am sure you realize are lower-end used camber plates.

Install the assembled plate/strut unit into the upper fender/tower using the three studs, lightly TQ them down but do not put lower strut into the steering knuckle. Using your hands or carefully placed tool, try to turn the lower strut body, see if you can break the spherical joint free inside the plate or see what moves if anything. It may just be frozen.

What may also happen if I am thinking about it right is the lower strut housing may rotate around the upper shaft/plate assembly, and the spherical won't budge. In that case see if you can free it by tilting it side side a bit. And maybe the design is such that it is not supposed to rotate, that is taken care of by the lower strut body rotating around the shaft as you turn the steering wheel. Not the best design but these are after all cheap used camber plates.

In the end you'd want to rotate it to the point that it is lined up right for install, give it a shot esp if you're going to get rid of them anyway. Or at least that's what I'd do. Then decide if you want to complete install and drive the car that way. If after all that steering feels as if it is binding or tight, def trash them.

edit: OK I maybe did not think that through correctly. In order for the lower strut body to rotate around the shaft, the spring would have to rotate with the strut body, and it can't do that up top if the spherical won't move as it is locked to the upper spring perch. So back to needing the spherical to move. Still worth trying partial install IMHO see if you can get the spherical to rotate.

[benton0311]

Looking at the latest version of the KMAC plates (google image link from Turner Motorsports Page): the newer version now has a center sleeve section to fit between the top nut and conical washer (conical washer->center sleeve->top nut). The plates look the same otherwise. So, at least based on that design, it does look like the fitment of the top nut/conical washer shaft (and now center sleeve/shaft) inside of the spherical bearing is exact and that the shaft would rotate inside the spherical bearing.

[ajsalida]

Originally Posted by benton0311

Looking at the latest version of the KMAC plates (google image link from Turner Motorsports Page): the newer version now has a center sleeve section to fit between the top nut and conical washer (conical washer->center sleeve->top nut). The plates look the same otherwise. So, at least based on that design, it does look like the fitment of the top nut/conical washer shaft (and now center sleeve/shaft) inside of the spherical bearing is exact and that the shaft would rotate inside the spherical bearing.

Actually what I see is a "self lubricating radial bearing" spring perch assembly (pic 3) which would fix all of your problems

http://www.turnermotorsport.com/p-13...eettrack.aspx#

[benton0311]

Those particular perches are 60mm but I wonder if they have them available for standard size springs. I may still look into getting a set of thrust bearings to install where the 6mm spacer sits above the spring plate. I think the general consensus is that is where the binding is occurring and not the top nut as I had originally thought.

[ajsalida]

Originally Posted by benton0311

Those particular perches are 60mm but I wonder if they have them available for standard size springs. I may still look into getting a set of thrust bearings to install where the 6mm spacer sits above the spring plate. I think the general consensus is that is where the binding is occurring and not the top nut as I had originally thought.

Well in that case it is a mystery why they'd see a need for radial bearing type of set up with 60mm but for standard size nothing? Sorry, this must be driving you nuts.

BTW if your set up were supposed to rotate inside the sleeve, it'd probably destroy the inside face of the spherical just from friction in a short time, considering the constant load it is under with no lube or real bearing in place.

edit: actually reading the description on Turner's site it says the 60mm perches and radial bearing is to eliminate spring binding. Which to me means when you use them on stock diameter springs w/o the perches and radial bearing, you'd get binding, which is what happens when the lower strut body turns WRT fixed upper strut. SO maybe they are "supposed" to do that, as bad as that sounds.

[benton0311]

I messed around with them last night with the spring/spring plate removed (strut and camber plate only) and came to the conclusion that, as long as the top nut is torqued down on the strut, the camber plate will not allow the strut to turn inside of it due to the spherical bearing being clamped. The only solution would be to install thrust bearings both on the top (between spherical bearing and top nut) and the bottom (between spring plate and bottom washer) of the plate, which would be impractical for a several reasons.

With a thrust bearing mounted on the bottom only, the strut body and spring assembly would be able to turn but the strut shaft would be fixed to the plate. My understanding is that the strut body and strut shaft should move together when turning, not the strut body around the shaft as this would cause premature wear of the internal seals. Is this correct or can the strut shaft remain static while the strut body turns around it?

The only other option, and this is a long shot, is to loosen the threaded speherical bearing assembly, lube the threads, and allow the threaded portion of assembly do the turning. I don't see this being viable for very long as I would think the loosened threads would take quite a beating. This, however, is how I believe the original owner and maybe others who claim to have had no issues, believed that the plates work just fine as it's the only point of axial rotation thats possible.

[feuer]

Originally Posted by benton0311

My understanding is that the strut body and strut shaft should move together when turning, not the strut body around the shaft as this would cause premature wear of the internal seals.

No, as some OEM assemblies, M car in particular, implement guide support that prevents the strut shaft to move together with the rest of the assembly.
Additionally, most adjustable camber plate not allow that as well and it will not cause premature wear.