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      01-26-2013, 12:32 AM   #23
UltraRacer13
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pits- 2 questions
1- did you have to unload both sides of the car at once, ie remove both wheels and jack up both hubs?
1a- - i only have one jack so to deload the endlink I usually jack up the car and then place jack stands under the hubs and lower the car on the hub- do you see a fault with this method?

2- did you ever notice thie issue I mentioned about the way the collar on the AST is offset. I tried to explain further on my thread.

I am so glad you have done this. As you know I have been messing with my endlinks lately as well. My issue began with trying to fit 9.5s up front and the endlink collar getting in the way. I ended up getting adjustable endlinks from Harold delivered today. I really appreciate your write up on how to figure out where to set them.
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      01-26-2013, 01:00 AM   #24
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follow up pits....
to figure out the right length, ie the proper no load stting, couldn't I jack up one side, put a jack stand under the hub, then jack up the other side and then lower it on a jackstand.

Voila, car is loaded like driving position with all the weight on the suspension.

Also, I noticed my endlink was rubbing my drive axel due to its angle being poorly set. Do you think my sway has already been rotated improperly? How is it supposed to be orientated? looking at your pic you suggest the mounting point is to be in line with the straight part of the bar. or on the same plane as the ground. Is that correct.
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      01-26-2013, 06:26 AM   #25
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Quote:
Originally Posted by UltraRacer13 View Post
follow up pits....
to figure out the right length, ie the proper no load stting, couldn't I jack up one side, put a jack stand under the hub, then jack up the other side and then lower it on a jackstand.

Voila, car is loaded like driving position with all the weight on the suspension.

Also, I noticed my endlink was rubbing my drive axel due to its angle being poorly set. Do you think my sway has already been rotated improperly? How is it supposed to be orientated? looking at your pic you suggest the mounting point is to be in line with the straight part of the bar. or on the same plane as the ground. Is that correct.
I think you and I are going in the same circles with figuring this sway bar stuff out. I've tried asking Harold at hp about the orientation of the sway but I couldn't understand the answer. I think it is suppose to be aimed at the 5oclock position. As for how you loaded your car I think that should work just fine. It just worries me since the hubs have small lips for the jack to be set on.

Back to the bar orientation. I can't imagine it'd rotate easily or else it could get thrown off even if the endlink was mounted properly.

I just think the final question is what angle should the bar be at and you answered the question about where the mounting point should be on the strut.
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      01-26-2013, 08:26 AM   #26
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to be clear- I have to lift both wheels off the ground simultaneously though right?
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      01-26-2013, 10:10 AM   #27
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to be clear- I have to lift both wheels off the ground simultaneously though right?
Ya that would be the best way but one at a time would get you close enough.
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      01-26-2013, 10:49 AM   #28
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Another way would be to make some ramps out of 2x10's so you could adjust with the car fully loaded up on both tires. You can adjust sway bar bushings, toe links and lower sway bar links. Not sure about upper or the collar on your AST's. I can fit 2 thicknesses of 2x10's under the front spoiler (lowered on Eibach sports), this is how I do my redneck alignments and other qicky stuff without the hassle of jack points etc.

It is possible to get the entire underpanel off but it is a tight squeeze, so if I need to do that I drive up on the ramps, use the center jack point, put it on jack stands, remove the panel, lower it back down and drive back off and then onto the ramps again. (the car is too low to get a floor jack to the center jack point on the subframe, that is why I made these ramps)
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      01-27-2013, 01:32 PM   #29
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my sway seems to want to contact the control arm on the bottom in its "unloaded" state. I tried to rotate it a bit to no avail. I can adjust my endlinks and my strut collar but it just seems to have issues with the control arm.

Also pits- I found by pointing the endlink mount on the ast collar towards to front of the car the best orientation.
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      01-27-2013, 09:02 PM   #30
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I was thinking about this more in case I needed to do something. The strut bar looks for a height differential from one wheel to the other wheel. If your taking a corner, the inside wheel wants to compress and the other side wants to raise. That response wants to twists the sway bar and the sway bar resists this motion. Two variables is the pivot point (bushing mount) and the length of the lever arm (sway bar where it attaches to the end link). The end link just translate the motion of the wheel to the sway bar.

I could see a very minor difference due to the end link length difference looking from a trigonometry sense, but that difference would be relatively minor (even at a 2" difference) compared to manufacturing tolerance stack-up. I wonder if the height difference from the xi to the i is to clear the extra driveshaft?

pits200, when you were checking the end links, was both front wheels off the ground, or just one side jacked up? If only one side, then it might explain the preloaded condition. I think that may also be the reason they have you jack up the entire front end before you change out springs.

Last edited by critical05; 01-27-2013 at 09:10 PM.
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      01-27-2013, 10:04 PM   #31
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Ultra- Sorry I wasn't able to connect with you today

Critical, we need to remember that as an xi, our cars are going to drop more than the guys with i's since their stock height is much more reasonable. Meaning that the endlink effect can be much worse on our cars due to the preload.

Once the weather warms up here I am going to get both sides off the ground at the same time and see how things look with preload. Since you're right, I just measured each side with only 1 side up at a time which more than likely biased things a little.

I just ordered front and rear adjustable endlinks but don't think I'll be putting on the fronts anytime soon.
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      01-27-2013, 11:03 PM   #32
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      01-27-2013, 11:06 PM   #33
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so, I ended up lifting the entire front end off the ground on jackstands. Then i released both OEM endlinks. Here were the issues I faced.

I was able to jack up one side only to set the sway as I wanted it with no lead. My sway plays in a small range. Too low and it hits the control arm (rests on it) too high and it will rotate up and contact the drive axel.
The question was how to deal with the fact I couldn't simulate both wheels on the ground at the same time. I really needed 2 jacks. I had 2 choices- fit one side then mount the wheel and drop then do the other side. Or just match the second side to the original side as far as endlink length/ collar height (I counted threads).

I kinda did both, first matching them up then adding the wheel and double checking. For me, I didn't end up making a big change in length. But I did change the orientation, by shifting the endlink mount to face forward. I had been having an issue with the endlink contacting the drive axel, actually carving a divot in it. By moving the mount forward, the angle was improved, more upright, and solved this issue.

Overall, I found better ride quality than I expected. The car is smoother over bumps. I did not anticipate this, since I didn't move the endlinks much, but it may have been due to the orientation change.
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      01-28-2013, 10:03 AM   #34
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Guys you cannot do this properly unloading one side at a time.

Gonna make a wild suggestion and that is before installation the AST's link collar should have been set up to match OEM strut sway bar tab attachment point both height and orientation. It appears that is possible and the fact that these weren't is likely the cause of all your problems. You could just measure a stock strut and find out how far the tab is from the top of the knuckle and do that one side at a time, and then rotate the collar so it faces the right way (it sounds like this is possible). Then you do not need aftermarket links and you should have no binding or interference.

The OEM links are designed so that there is no contact with anything for the entire suspension travel and lock to lock on the steering. So I find it hard to believe there is any cause for concern for folks using slightly lowered suspensions provided the links are properly oriented and at the right height. I could be wrong of course.

FYI with the suspension loaded the link should be nearly vertical and close to parallel to the lower strut body. Then where it attaches to the bar, the sway bar arm at right angles to the link and parallel to the ground. Meaning if you look at it from the side, the bar inside the bushing is one point, the attachment to the link is another, a line of length L between those points should be horizontal WRT the ground and perpendicular to the link. The bar on the XI is curved to get around axles and so forth, but the forces are transmitted in the way described, that is how sway bars work. They apply a twisting force to the torsion bar tangent to the circle of radius L.

The only possible other source of binding is the sway bar bushings themselves sticking to the bar and preventing it from rotating. But these are supposed to let the bar rotate as the whole purpose of an anti-roll bar is to provide stiffness against roll, not extra spring rate on symmetrical bumps. Weather is preventing me from looking at the bushings on my car, as soon as I get a break I will and post here.

Last edited by ajsalida; 01-28-2013 at 10:08 AM.
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      01-28-2013, 01:34 PM   #35
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So I thought i'd draw this out and see if I could make heads or tails out of it.

The strut mounting point for the endlink is fixed. It doesn't matter if the car is lowered or original (unless aftermarkets struts have this mount lowered to account for lowering springs). The pivot point of the sway bar is the bushing and is attached to the car. When you lower your car your moving this mounting point down (shown in the pic).

Since the lever arm of the sway bar is a fixed length, and the endlink is a fixed length (13.5"), the endlink will need to rotate slightly counterclockwise to account for the drop. If the endlink was perfectly vertical, and now has rotated to 5 degrees, assuming a 13.5" endlink and a 5 degrees rotation (cosine problem) you will lose 0.004" for every 1" of suspension travel. Not much of a difference. The 5 degree was a hypothetical number.

As long as the new orientation doesn't interfere with other suspenion parts i wouldn't think this is much of a problem.

On second thought the endlink would rotate clockwise, not counterclockwise as the drawing suggests.
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      01-28-2013, 01:58 PM   #36
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Looking at mine- It appears to have a somewhat limited range of motion between the drive axel and the lower control arm. I know it hits the lower arm (rests on it when the wheel hangs. I did not fully rotate it up to see if it would hit the drive axel, but it certainly looked like it would contact it. That left it only about 5-8 inched of range.



This pic shows the resting position with the wheel hanging all the way. Notice the poor angle of the endlink that I believe is due to the placement of the endlink mount on the AST strut. With my new links, I was able to rotate the collar forward because the adjustable links can swivel a full 360 degrees on both ends. Also note the groove that was being worn in the drive axel due to the link leaning back like it is in the picture. NOT GOOD.

You guys tell me, can the sway bar be rotated up without contacting the drive axel??
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      01-28-2013, 03:09 PM   #37
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Quote:
Originally Posted by critical05 View Post
So I thought i'd draw this out and see if I could make heads or tails out of it.

The strut mounting point for the endlink is fixed. It doesn't matter if the car is lowered or original (unless aftermarkets struts have this mount lowered to account for lowering springs). The pivot point of the sway bar is the bushing and is attached to the car. When you lower your car your moving this mounting point down (shown in the pic).

Since the lever arm of the sway bar is a fixed length, and the endlink is a fixed length (13.5"), the endlink will need to rotate slightly counterclockwise to account for the drop. If the endlink was perfectly vertical, and now has rotated to 5 degrees, assuming a 13.5" endlink and a 5 degrees rotation (cosine problem) you will lose 0.004" for every 1" of suspension travel. Not much of a difference. The 5 degree was a hypothetical number.

As long as the new orientation doesn't interfere with other suspenion parts i wouldn't think this is much of a problem.
Yes that is exactly it, nice pic. I would add only that if the AST tab isn't oriented same as OEM, and you use OEM links, now you are twisting the link into a different plane entirely. That shorten the link's effective lever arm about the bar, and it brings it in possible contact with other parts, not to mention possibly binding up the ball joints inside the link's two end points as it moves.

But lowered with OEM links and OEM style tab orientation (Konis or Bilsteins, maybe KW's) there should be zero problems, as this is well within the operating range of motion of the 100% stock suspension.
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      01-28-2013, 03:24 PM   #38
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i may be back tracking now. After studying my drawing a bit more. The only way to return the sway bar to the original angle would be to increase the length of the endlink as Pits200 did. This would rotate the sway bar down and back to its stock angle. By lowering the car and rotating the endlink clockwise means that it is just that much closer to the halfshaft.

Pits200, when you adjusted the endlinks, what was the final length?

I wonder if thats what i've heard when the wheels are fully turned, like when parking. I've heard a clicking noise around the wheel, this only happens when i'm at full lock and on one side. Maybe its the endlink hitting the halfshaft or the little metal clamp on the dust boot. Will need to take a look at both so see if there is any sign of contact or abrasion.
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      01-28-2013, 03:57 PM   #39
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From HP Autowerks. Need to go longer

When you lower the vehicle, the swaybar is moved from the ideal factory geometry to an offset that decreases the ability of the swaybar to perform. The swaybar frame mount and the end of the bar should be on the same horizontal plane. The factory end links are a solid piece. When the car is lowered, the OEM links cannot compensate for the longer length needed to keep the swaybar in its ideal location. Get immediate response from your sway bar and precise control over your suspension. What this means to you is tighter, more responsive handling.
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      01-28-2013, 04:01 PM   #40
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jeguth1s;

You found the same link as me. Now i need to see if they make it for the XI's

http://www.e90post.com/forums/showthread.php?t=331670
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      01-28-2013, 04:06 PM   #41
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Quote:
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jeguth1s;

You found the same link as me. Now i need to see if they make it for the XI's

http://www.e90post.com/forums/showthread.php?t=331670
I just bought them from Harold- and put them on my car yesterday. I got essentially the M3 endlink. It comes with a min length of 13.5 inches and will expand to 15. With my AST's and the adjustable collar I felt this was all i needed. Harold can have them made to any desired length in 2 weeks.
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      01-28-2013, 04:15 PM   #42
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I have koni yellows so i just contacted Koni. They said that the endlink mounting location on the yellows are based on stock location.

They said with the modest drop on the eibach pro springs that I don't need longer endlinks. He said it could increase wear slightly.

I'll have to take a look with the wheels lock to lock on the ground to see if new endlinks may be justified. I don't have any issues with the car staying flat on turns, its just a mental thing now.
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      01-28-2013, 04:16 PM   #43
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Quote:
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jeguth1s;

You found the same link as me. Now i need to see if they make it for the XI's

http://www.e90post.com/forums/showthread.php?t=331670
My bad i didn't read the entire thread.
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      01-28-2013, 04:30 PM   #44
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No issues, you actually found and posted it first. I just was making a comment and attaching the link to it.

I found another link on the 1 forum that addresses that most won't notice the difference between the small change in suspension geometry. The TC kline guy saids the mounting location is more important.

http://www.1addicts.com/forums/showthread.php?t=537053
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