Addco front sway bar
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Addco front sway bar
I replaced my 3/4" front sway bar on my '72 SB coupe with an Addco 1" bar. The problem I found is that the ends of the bar connected to the links are bent, making it impossible for the bushings to seat properly.
And just to experiment, I flipped the bar upside down and still found that the bends at the ends of the bar will not allow the bushings to seat.
The only conclusion I can make is that the ends of the bar should not be bent at all and should align with the center line of the bar. I've looked at other sway bars and they also have bends at the ends, so I'm at a loss as to why this is.
Has anyone else run into this? If so, what did you do to fix the problem? I will most likely take the bar to a spring shop and have the ends straightened so that the bushings fit properly.
And just to experiment, I flipped the bar upside down and still found that the bends at the ends of the bar will not allow the bushings to seat.
The only conclusion I can make is that the ends of the bar should not be bent at all and should align with the center line of the bar. I've looked at other sway bars and they also have bends at the ends, so I'm at a loss as to why this is.
Has anyone else run into this? If so, what did you do to fix the problem? I will most likely take the bar to a spring shop and have the ends straightened so that the bushings fit properly.
Melting Slicks
Joined: Feb 2006
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From: Sunrise FL
Did you check the end position with both wheels back on the ground? Makes a BIG difference.
OEM bars have a slight bend in the center that should face down for clearance, does your bar have that?
Or I would call addco.
OEM bars have a slight bend in the center that should face down for clearance, does your bar have that?
Or I would call addco.
Last edited by mikem350; Mar 30, 2016 at 10:45 AM.
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Yes, the bar does have the bend for the center section of the bar to clear the underside of the fan shroud. But even that is not correct. With the bar installed 'correctly', the center section does not hang as low as it should. The center section is oriented somewhat toward the rear by about 15 degrees.
When I installed the bar in what should be the upside down position, the center section clears the underside of the fan shroud by about 1/2" and is facing nearly straight up. However, the bushings are still misaligned the same amount, just reversed.
This is what leads me to believe that the ends of the bar should have no bends where the links/bushings connect. I.e. If the ends of the bar were straight, and on the same axis as the bar, the bushings would seat correctly.
Race Director
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see this link, I see nothing wrong with your bar
https://www.corvetteforum.com/forums...ar-1980-a.html
and this article with pictures
https://www.corvetteforum.com/how-to...way-bar-368648
https://www.corvetteforum.com/forums...ar-1980-a.html
and this article with pictures
https://www.corvetteforum.com/how-to...way-bar-368648
Last edited by MelWff; Mar 30, 2016 at 02:26 PM.
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see this link, I see nothing wrong with your bar
https://www.corvetteforum.com/forums...ar-1980-a.html
and this article with pictures
https://www.corvetteforum.com/how-to...way-bar-368648
https://www.corvetteforum.com/forums...ar-1980-a.html
and this article with pictures
https://www.corvetteforum.com/how-to...way-bar-368648
Thanks for your comments and links.
Unfortunately, in both pictures the cars are up on lifts, so the sway bars are not in the position they would be if the car was on the ground and the suspension loaded. When lowered to the ground the ends of the sway bar will rotate upward, thus increasing the misalignment of the bushings and link bolt. The problem is easier to see in the second picture.
Re: Lionelhutz comment.
I'm not clear on your suggestion. However, there are only two ways to mount the bar and I've tried both and gotten the same results. Installing spacers of different lengths, whether longer or shorter, will only screw up the geometry, and therefore the function of the sway bar.
IMO, the ends of the sway bar should be straight. I will be in touch with Addco, but I doubt they will be of any help. It's been my experience that today's manufacturers couldn't care less about customer satisfaction or correcting defects in their products. I would really like to be proven wrong. We'll see...
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The longer links will rotate the bar a bit which changes the angles of the ends. But, you don't believe me and you can have fun figuring it out yourself.
Last edited by lionelhutz; Mar 30, 2016 at 06:02 PM.
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It's very easy to understand that the portion of the sway bar from the end to the first bend must be horizontal. Otherwise, the rotation of the end sections and the twist of the bar will not work correctly.
You are correct. I don't believe you. And the solution has already been figured out. I can't say that it was "fun" exactly, but it was gratifying. A mechanical engineer (former coworker) I spoke with, the bend at the ends of the bar should not be there. The eyes through which the link bolts pass must be horizontal, or perpendicular to the link bolts. The end section must be horizontal as well. Ta da!
Race Director
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You're making a mountain from a mole-hill. Can you even explain why the rearward facing bars "must" be horizontal for it to work correctly?
Many factory bars have some angle to them. A small angle on on the bar will make so little difference in any forces that it won't make any significant difference in the operation of the bar. Besides, how "square" do you think the end and the link are when the suspension travels?
Many factory bars have some angle to them. A small angle on on the bar will make so little difference in any forces that it won't make any significant difference in the operation of the bar. Besides, how "square" do you think the end and the link are when the suspension travels?
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You're making a mountain from a mole-hill. Can you even explain why the rearward facing bars "must" be horizontal for it to work correctly?
Many factory bars have some angle to them. A small angle on on the bar will make so little difference in any forces that it won't make any significant difference in the operation of the bar. Besides, how "square" do you think the end and the link are when the suspension travels?
Many factory bars have some angle to them. A small angle on on the bar will make so little difference in any forces that it won't make any significant difference in the operation of the bar. Besides, how "square" do you think the end and the link are when the suspension travels?
I think part of the problem here is that it's difficult to see the extent of angular misalignment from the picture I posted. The angle of misalignment is between 15 and 20 degrees, which makes the eye at the end of the bar far from perpendicular to the link bolt. To correct this by changing the length of the spacer would be too extreme and would defeat the functionality of the sway bar.
I suggest to anyone following this thread who is genuinely interested that you take a look at the illustrations and white papers available online, which explain performance suspension geometry much better than I am able to do in this limited space.
Last edited by Dinther; Apr 1, 2016 at 02:46 PM.
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Exactly. With the sway bar set up as it is, there's the chance the bushings will be damaged and/or the link bolts may be bent. It's just not a good installation and will have to be corrected, somehow.
Race Director
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From: South Western Ontario
No need to search for suspension theory to understand a little basic geometry.
15* is a lever ratio of 96.5%
20* is a lever ratio of 94%
So, putting the arms at a 15* to 20* angle makes approximately a 3.5% to 6% difference in the rate of the bar. Once again, mountain out of a mole hill.
15* is a lever ratio of 96.5%
20* is a lever ratio of 94%
So, putting the arms at a 15* to 20* angle makes approximately a 3.5% to 6% difference in the rate of the bar. Once again, mountain out of a mole hill.
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No need to search for suspension theory to understand a little basic geometry.
15* is a lever ratio of 96.5%
20* is a lever ratio of 94%
So, putting the arms at a 15* to 20* angle makes approximately a 3.5% to 6% difference in the rate of the bar. Once again, mountain out of a mole hill.
15* is a lever ratio of 96.5%
20* is a lever ratio of 94%
So, putting the arms at a 15* to 20* angle makes approximately a 3.5% to 6% difference in the rate of the bar. Once again, mountain out of a mole hill.
Throwing a bunch of meaningless numbers at an obvious misfit of components serves absolutely no useful purpose. Some people just can't see the forest for the trees.
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Ditto. You've got it stuck in your head how it "must" be and can't see how you can make it line up better without any noticeable change in performance.
FYI, the bar will likely bend the bolts when it travels or the first time you unload the suspension. The links on the Addco bar in my Impala bent when I jacked the front end up. I don't consider it a big deal because it still works the same as before. The only way to solve the dynamic bending load the links see is with heim joints or some other kind of ball and socket joint.
Last edited by lionelhutz; Apr 1, 2016 at 06:08 PM.
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[QUOTE=lionelhutz;1591907419]Ditto. You've got it stuck in your head how it "must" be and can't see how you can make it line up better without any noticeable change in performance.
I understand the "Bubba" approach very well. It's just not the way I do things.
I understand the "Bubba" approach very well. It's just not the way I do things.
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LOL, just as Bubba as the factory, since there are 100's of thousands of Corvettes on the road that came from the factory without the swaybar ends parallel to the ground.
Last edited by lionelhutz; Apr 2, 2016 at 11:44 AM.
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