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i saw a few people do it so i figured i'd give it a try. this is what i came up with.
3/8x24 rod ends with a 1x1 aluminum square stock. dont know the wall thickness but its not that thick. so im a little nervous. if they cant hand it ill get thicker aluminum or step it up to steel. any feed back would be appreciated.



 

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there's a lot of angularity in the rod ends. u cant really see it but there's steel spacers between the rod ends and the aluminum tube so theres plenty of play before binding. im more worried about it almost pulling apart when one side is in compression and the other is in rebound. ill get pics up when i put them on.
 

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All smart-ass comments from me aside, take Jack's comment seriously and verify that you have enough angular clearance as the a-arm goes though bump and rebound. It can't hurt and will give you piece of mind knowing it won't go into bind. I applaud the
effort.
 

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I'm not talking about clearance between the rod end body and your aluminum end-link. I'm talking about the range of angularity that the rod end itself is capable of. The ball on the inside can only rotate so many degrees before the bolt going through it hits the outer race. A typical 3/8" rod end has a limit of +/-12 degrees. A high misalignment rod end has a limit of around +/-20 degrees. Generally, the larger the allowable misalignment, the weaker the rod end.

My guess is that in the first couple hours of use, the aluminum around the bolt holes is going to start tearing due to not enough cross sectional thickness and from the bending loads when the rod ends bind at full bump or droop. You really need to pull a front spring out on one side of the car. Remove both swaybar end-links. Lower the FCA to full droop. Try to install your end-link. You will probably find that you can't because there isn't enough combined angularity in both rod ends. If you can install it, great. Now jack up the FCA slowly until you get to full bump. You will probably find that the rod ends bind up before you can get to full bump, and your thin aluminum end-link is going to fold up.

Look at the car from the front view. The FCA is about 13" long. At the balljoint it can move a total vertical height of about 7" with stock struts. That is a big total angle change. (Free MM stickers to anyone that can correctly calculate what the angle change is. You MUST show your work) The combined angularity of both rod ends needs to be able to accommodate this angle change. Even if there is enough total angularity available, your design has no provision to adjust the phasing between the angularity needs of the FCA and the end-link.

This phasing is a bit hard to describe. Pretend that when your car is at ride height that your FCA is level. That means that the rod ends need to move through the exact same magnitude of angle (but opposite direction) at full droop and at full bump. In this case, the FCA and the end-link angularity are in perfectly in phase with each other.

Now pretend that at ride height, the FCA balljoint is 2" below the FCA pivots. In this case, the rod ends are forced to go through a much larger angle change at full droop than at full bump. At full bump, the rod ends are almost going to be in line with one another. At full droop, they are going to be at max angularity and the link is going to be bent 20 degrees or so. To make this design work in general, you must have some ability to adjust for this phasing problem.

I'm not trying to discourage you from doing this, I'm just letting you know about some of the design issues before you go too far down one particular path.
 

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Jack, is there a particular reason that you(MM) do not offer a rod ended endlink? There's already everything on your site to replace all the stock "crap" on Mustangs. ;)
 

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Jack, is there a particular reason that you(MM) do not offer a rod ended endlink? There's already everything on your site to replace all the stock "crap" on Mustangs. ;)
Probably because they feel it isn't needed.
 

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That was my second guess...
I'll admit I'm having trouble figuring out why you'd need stiffer swaybar bushings or endlinks.

The swaybar is a spring (a torsion bar, actually,) between the two sides of the suspension. Movement in both sides is not resisted. Movement in only one side causes the bar to resist that movement, since it's trying to compress the other side's suspension.

So since the bar is essentially a spring, any compliance in the endlinks or the bushings will be seen as a lower spring rate, initially. Once the endlinks and/or bushings have fully compressed, the bar starts twisting and the effective spring rate goes up -- you have, in effect, a progressive-rate spring.

The upshot of that would be, in my eyes, a bit more body roll, and a bit longer time required for the chassis to take a set on the corners -- but only a bit.

And seeing how some body roll is good, 'cause us humans seem to like it (driving a car with no body roll tends to be some=what more difficult -- our brains seem to want at least a little roll, apparently,) having a little compliance in the end links and bushings probably isn't all that bad.

My AI car runs factory bushings and Energy Suspension end links, only because the ES links are somewhat adjustable (cut the tube,) and the factory links aren't.
 

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I agree with you, as i'm sure you've got more time in the seat than me. I guess people just like to build stuff and see if it works.....especially things on a small scale/low investment.

I'm one of'em. ;)
 

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Or a person could be sick of having to replace their urethane endlinks because one of them keeps getting torn up and can't figure out why. :idunno:
 

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Or a person could be sick of having to replace their urethane endlinks because one of them keeps getting torn up and can't figure out why. :idunno:
:salute: I went through that. Maybe not at the level I remember you stating, but my upper/pass. side seem to get abused more than the others.
 

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. (Free MM stickers to anyone that can correctly calculate what the angle change is. You MUST show your work)

Just for fun:
a= 13, b=13, c=7.
Angle = arccos ((a^2)+(b^2)-(c^2))/(2ab)
= arccos ~.85
= ~.555 rad
= ~ 31*


However, can't you install the joint so that the angle of deflection of the link is perpendicular to the axis of the bolt? There is likely movement in more than one plane, but I would think that the angularity of the joint could be minimized by being smart about the install.

on further thought: The length of the arm of the sway bar is even shorter than the length of the control arm leading to an even greater change of angularity at the upper end of the link.

on further further thought, the horizontal offset of the lower link at full droop will only be about .5" therefore, by placing the axes of the upper and lower link non-parallel such that there is little angularity of either the upper or lower joint you should be able to eliminate the bind and breakage. This will be much easier to accomplish if you use a threaded tube for your endlinks with brackets bolted to the control arm and sway bar rather than a square tube construction as the OP has done.
 

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Discussion Starter #18
all good points guys. i just like making stuff to see if it will work. and since they are already made, all i gotta do now is throw them on, give a quick check and go for a drive and see what happens. u guys have me a little nervous now, but its only a swaybar end link. if they break then bring it home, and throw the stockers back on.
 
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