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Discussion Starter · #1 ·
I've started putting pencil to paper, and I developed a few under-tower mount concepts over the weekend, but I need your input.

First a question: Those eccentric circle camber plates out there, anybody know how far over they offset the top of the strut? Like, when they're turned all the way to one side, how far from center is the strut? 1"... 1/2"... and anybody have any concrete numbers on the resulting camber change?

Edit: Removed design information.
 

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Discussion Starter · #2 ·
Did a little searching, and this tells me a lot actually:



Thanks Murph!


That's about as far over as you could get a top mount plate, without starting to hog out sheetmetal. Murph, that gives you 1* camber? What would you do for more?

So, it sounds like the design brief would be:

-Mostly decoupled camber from caster adjustment. You could make both sides equal camber without screwing up caster. Camber adjustment would be easier to set, smoother...

-Would give 1* camber without touching sheetmetal. And 2-3* if you do remove sheetmetal.

-No more clunking noises, but maybe increased road noise transmission.

-Cost $2-300 with high quality teflon lined bearing you could hang a truck off.

Who'd be seriously interested?
 

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Inheritly Sinister
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I have those plates. I run about -1* on the street, and rotate them for the track to about -3*. Thats what the alignment machine said. Thing is, when I go to my track setting, it kicks my toe out, but it comes back in when switching back.

And no noises what so ever.

Hope that helps.
 

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Did a little searching, and this tells me a lot actually:



Thanks Murph!


That's about as far over as you could get a top mount plate, without starting to hog out sheetmetal. Murph, that gives you 1* camber? What would you do for more?
At my ride height my camber at the wheels is -2.25 to 2.50 or so. If mr. pyrometer is telling someone they need more, there is no doubt that you'll be cutting for your design right?.

There is no doubt seperating camber/caster is the "real" approach, but I think I'm "set and forget" for now.
 

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Discussion Starter · #5 ·
Does that thing have any angular compliance in it at all? I haven't played with one. The stock mount has angular compliance, which it NEEDS, otherwise you're going to be trying to bend the shock shaft as it goes up and down. Anybody know?
 

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Does that thing have any angular compliance in it at all? I haven't played with one. The stock mount has angular compliance, which it NEEDS, otherwise you're going to be trying to bend the shock shaft as it goes up and down. Anybody know?
I don't remember any 'angular compliance' when I installed mine. The nut sandwitches things tight.


This is not good...How come nobody pointed this out before? Are you sure its necessary?
 

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Discussion Starter · #7 ·
Are you sure? It's pretty much mandatory. The stock strut mount has rubber between the cup, and the mount plate. The plate is bonded to cup with rubber, and that rubber provides angular compliance.

Think about it, as the suspension travels up or down, the angle of the strut relative to the body changes continuously. *Something* between the body and the strut rod has to let that movement happen. If not, you're either flexing the strut shaft, or the plate itself. In either case, the resulting load on the shaft would cause a lot of internal friction in the strut, wear it out faster, possibly fatique the shaft or the plate...

I know those little disks are rigid with the little cup they mount to, but what about the cup to the plate? Like, the inner cup thing with the lip that the plates sandwhich, is that lip/cup thing solid with the mounting plate, or is there rubber somewhere?
 

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I know those little disks are rigid with the little cup they mount to, but what about the cup to the plate? Like, the inner cup thing with the lip that the plates sandwhich, is that lip/cup thing solid with the mounting plate, or is there rubber somewhere?
It's a noteworthy issue. They put a very, very dense material on the mounting plate, probably just enough to provide the angle, and be almost completely rigid once assembled. I think this "angle" and the non-compliance is probably the source of some peoples clunking when the assembly loads and unloads. I don't have have any undue noise at this point, I could see it happening though, if someone is running too low a ride height with a ton of rebound damping.
 

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Did a little searching, and this tells me a lot actually:



Thanks Murph!


That's about as far over as you could get a top mount plate, without starting to hog out sheetmetal. Murph, that gives you 1* camber? What would you do for more?

So, it sounds like the design brief would be:

-Mostly decoupled camber from caster adjustment. You could make both sides equal camber without screwing up caster. Camber adjustment would be easier to set, smoother...

-Would give 1* camber without touching sheetmetal. And 2-3* if you do remove sheetmetal.

-No more clunking noises, but maybe increased road noise transmission.

-Cost $2-300 with high quality teflon lined bearing you could hang a truck off.

Who'd be seriously interested?
Are we talking about conventional springs or coilovers in this design brief? As far as I'm concerned: Springs = very interested; coilovers--less interested.
 

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For discussion purposes:
 

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Discussion Starter · #11 ·
Back to those other plates, it appears they have something rubber in there, so they can deflect somewhat. However, even with some rubber, it will still cause a bending load in the rod. Read Maximum Motorsport's webpage for some more info:

http://www.maximummotorsports.com/cc.asp

Dynamic alignment accuracy is the ability of your Mustang to maintain its static alignment settings during hard cornering. This accuracy is not possible with the stock rubber strut mounts because they deflect, allowing the camber and caster settings to fluctuate, which changes the effective toe setting. Any time the effective toe setting changes it creates a steering input which is not coming from the driver. When engineering our Caster/Camber plates, we discovered that the only design which allows the necessary strut top movement is a spherical bearing. The desired movement is a strut top which swivels without moving side to side, while the strut bottom is allowed to move in an arc.
The MM plates use a spherical bearing instead of a urethane bushing. A spherical bearing accommodates the required motion without binding. Urethane binds and puts a bending load on the top of the strut shaft, which may cause your strut top to break.
 

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Yep, there is no doubt the load is there, and that, along with the simple, co-dependent camber/caster adjustment of this design.........reveals what an $80 solution is like versus a $200 or more, thoroughly developed application.

Definitely not your rally choice I guess
, though I will feel quite heroic if any of my antics break the top of my struts.

sighs deeply while in denial of the desire to change every darn suspension component.... again.......
 

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Rob, I have the specialty products ones sitting in my bedroom right now waiting to go on the car. If you are coming to town soon you can take a look at them.
 

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Discussion Starter · #14 ·
Is there any desire to have adjustable caster too?

Edit: Just removing design information.
 

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Pulling a naz here

What about something like this?


That disc at the bottom is to show what the inside would look like. It would be one piece, so caster is locked. For camber adjustments, loosen the bolt, and slide to the desired position. Won't give too much, but you can run any camber inbetween without mess up your caster.

Or would this not work?
 

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Discussion Starter · #17 ·
I think it's a pretty bad idea... All the lateral stress at the top of the strut is being resisted by ONE bolted joint, which only has like 30% contact area at that.

It would be constantly changing camber settings. And there would be strength issues with it.

Basically, the top of the rod would make a mess out of that slot pretty quick. There's just not enough bearing area left after the slotting.

I just came up with a new idea... well I'm gonna call it pretty inspired. Definitely moving forward with this. I'll be picking up some bearings maybe tomorrow if I can find someplace local, and start cutting metal.
 

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I would love to have adjustable caster in addition to camber. If it were a difference between $200 and $250, no question I go for it. I've been reading about how some people believe hard core in caster being the key. Apparently some BMW race teams run up to 15 degrees (neg or pos?) to get crazy negative camber in the corners but less down the straights.
 

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Discussion Starter · #19 ·
One thing about caster is, too much can ruin your struts. It can help handling, it was a big thing on Mustangs too. But I'm going to be careful with that. It's a real toss up. It can make a big difference in cost and complexity, with a minor increase in performance, and a decrease in strut durability.
 

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Here is some ramblings about the true or perceived value of more postive caster....

Tech-Talk Caster

It seems to mirror what I've read from Don Alexander and others......some more caster can be a good thing, much more is overrated.....particularly how much camber is gained.
 
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