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-   -   Anyone broken a rear swaybar endlink before? (https://www.rx8club.com/rx-8-racing-25/anyone-broken-rear-swaybar-endlink-before-186007/)

EricMeyer 11-24-2009 06:05 AM


Originally Posted by Spin9k (Post 3325507)
How much did you car weigh Eric, and what was the front/rear balance % when using no rear bar?

Interesting question. Not sure if I understand it correctly.

Our first two cars ran about 2,660 no fuel, no driver. Rear weight % runs about 48.5 - 48.7

The absence of a rear bar or the size of bars does not effect the rear weight % of the car to my understanding.

Again, when you set up a car you'll want to dissconnect the links thus removing any influence the bar brings to the car and any influence you'd see on the scales. Some people call the dissconnecting of the links "neutralizing the sway bars"----at least they do round these parts.

Spin9k 11-24-2009 06:48 AM


Originally Posted by EricMeyer (Post 3328112)
Interesting question. Not sure if I understand it correctly.

Our first two cars ran about 2,660 no fuel, no driver. Rear weight % runs about 48.5 - 48.7

The absence of a rear bar or the size of bars does not effect the rear weight % of the car to my understanding.

Again, when you set up a car you'll want to dissconnect the links thus removing any influence the bar brings to the car and any influence you'd see on the scales. Some people call the dissconnecting of the links "neutralizing the sway bars"----at least they do round these parts.

Thanks. I wasn't meaning that 'no rear bar' had anything to do w/% weight balance, just interested in the effect of what you do to strip the car weight down/(re)move fuel tanks (if you do), etc., and how that might play into that hi-rate front bar only setup.

What I was trying to get straight in my mind is how giving the car massive understeer tendencies in the front with a strong bar could be adequately balanced out with only -and no bar- equally stiff rear springs /shocks modifications (at least that what I think you are saying). And given that the adjustment can be done, that the rear grip is ok (not too much like a solid axle/aka 'no' suspension) with the degree of stiffness that it seems would be required. Perhaps it's no so major, dunno.

I'm thinking the idea mentioned that it's easier to just mess with one end of the car at track (when you have a pit crew) is the reasoning, rather than any true benefit over a more normal front/rear adjustable sway bar setup and (as I do) using the adjustability of coilovers shock valving to make minor front/rear stiffness adjustments to suit a track or driver desires.

Also, When my car was corner weighted one endlink each end got removed and when it was done one adjustable endlink was installed each end to keep neutral preload.

EricMeyer 11-24-2009 07:33 AM


Originally Posted by Spin9k (Post 3328125)
Thanks. I wasn't meaning that 'no rear bar' had anything to do w/% weight balance, just interested in the effect of what you do to strip the car weight down/(re)move fuel tanks (if you do), etc., and how that might play into setup.

What I was trying to get straight in my mind is how giving the car massive understeer tendencies in the front with a strong bar could be adequately balanced out with equally stiff rear springs /shocks modifications (at least that what I think you are saying). And given that the adjustment can be done, that the rear grip is ok (not too much like a solid axle) with the degree of stiffness that it seems would be required.

I'm thinking the idea mentioned that it's easier to just mess with one end of the car at track (when you have a pit crew) is the reasoning, rather than any true benefit over a more normal front/rear adjustable sway bar setup and (as I do) using the adjustability of coilovers shock valving to make minor front/rear stiffness adjustments to suit a track or driver desires.

Creating new post for this. Long voluminious discertation to follow.

chiketkd 11-24-2009 08:30 AM


Originally Posted by TeamRX8 (Post 3327532)
Note the later reply about "iffy" rear links somehow being interpreted as justification for replacing them First with aftermarket adjustable. Despite a few bad apples causing a TSB, the rear endlinks are nowhere near being the weak link in an RX-8 suspension. They're the same link as the front, just shorter. So they have a much greater stiffness ratio, yet see nowhere near the stress loading of a front endlink. What exactly makes them "iffy" anyway?

To clarify, my "iffy" statement was referring to the length of the stock rear endlinks and their ability to not exert any preload on the RSB (not their strength).

This is a pic expo1 posted of a RB rear swaybar installed on his car;

https://www.rx8club.com/attachment.p...6&d=1099331091

Mine looks like this installed (dip in the arm pointing down), except that with the additional 1/2" koni drop, the swaybar arm ends are pointed upwards even more. If I lowered the car another 1" or thereabouts, I'm concerned that my stock endlinks would push the arm ends even further upwards causing potential preload issues on the bar and/or binding in turns if the RSB arm ends run out of longitudinal travel.

burglar 01-16-2010 04:10 PM

Well, heard a loud "pop" pulling out of work yesterday - and sure enough the other side endlink gave way. WTF.

The bar seemed to rotate freely in the mounts when I replaced the last one. Guess I'll just replace it any cross my fingers.

Spin9k 01-16-2010 07:36 PM

Did you ever verify your rear sway wasn't installed upside down (the common mistake)? The most likely answer since you don't know the car's history and truth is your more likely to be hit by a meteorite than have 2 endlinks on the rear break only a couple months apart on the same car for no good reason.

If you don't fix the source of the problem, whatever it is, the failures will just continue...

TeamRX8 01-16-2010 09:21 PM

There was a bad run of OE endlinks and he could have easily had two of them on there :dunno:

and you'll run out of shock travel long before the properly mounted rear bar with OE endlinks hits the subframe


and Chik, the end direction is meanigless in your picture post above. It's the link hole position relative to the pivot point that matters (draw the imaginary straight arm line between the two points in your head) and there's no way you can rotate it that much because it will hit the subframe first, and it can't rotate that far before the shock travel gives out. Lowering only means it runs out of shock compression travel sooner.






.

kwikslvr 01-25-2010 01:24 PM

all of this talk about endlinks has got me to thinking... I lowered my car with sprint springs, about a 2 inch drop, and i had to cut the rear endlinks because they simply would not come off. i then ordered OEM replacements and put them on the car, but now that i think about it, i did exactly what you said not to. i tightened them down all the way while the car was in the air. However, following my ignorant move there i had an alignment done by a speed shop in the area here. Question is then, would that have been checked when i had the alignment done? and also if i loosen them and re-tighten them while on the ground, just to be sure, can that affect my alignment and cause me to have to get another one?

thanks in advance.

Bigbacon 01-25-2010 02:46 PM


Originally Posted by kwikslvr (Post 3401631)
all of this talk about endlinks has got me to thinking... I lowered my car with sprint springs, about a 2 inch drop, and i had to cut the rear endlinks because they simply would not come off. i then ordered OEM replacements and put them on the car, but now that i think about it, i did exactly what you said not to. i tightened them down all the way while the car was in the air. However, following my ignorant move there i had an alignment done by a speed shop in the area here. Question is then, would that have been checked when i had the alignment done? and also if i loosen them and re-tighten them while on the ground, just to be sure, can that affect my alignment and cause me to have to get another one?

thanks in advance.

end links has nothing to do with the alignment. tightening or loosing them won't hurt it.

How in the world are you going to get under the car to mess with the end links once it is on the ground anyway? Might be best just to put a jack under the wheel hub and lift it then mess with the end links. Put the car on jack stands first.

chiketkd 01-25-2010 03:10 PM


Originally Posted by TeamRX8 (Post 3390950)
and Chik, the end direction is meanigless in your picture post above. It's the link hole position relative to the pivot point that matters (draw the imaginary straight arm line between the two points in your head) and there's no way you can rotate it that much because it will hit the subframe first, and it can't rotate that far before the shock travel gives out. Lowering only means it runs out of shock compression travel sooner.

Thanks Mark. I would have to agree with everything you stated. 2 months ago, that post of yours would have made no sense to me...

dannobre 01-25-2010 03:18 PM


Originally Posted by kwikslvr (Post 3401631)
all of this talk about endlinks has got me to thinking... I lowered my car with sprint springs, about a 2 inch drop, and i had to cut the rear endlinks because they simply would not come off. i then ordered OEM replacements and put them on the car, but now that i think about it, i did exactly what you said not to. i tightened them down all the way while the car was in the air. However, following my ignorant move there i had an alignment done by a speed shop in the area here. Question is then, would that have been checked when i had the alignment done? and also if i loosen them and re-tighten them while on the ground, just to be sure, can that affect my alignment and cause me to have to get another one?

thanks in advance.


The sway bar end links aren't a problem..they fully rotate

The suspension links are the ones you want to tighten in a neutral position...

JinDesu 01-25-2010 05:17 PM

I don't know if this is of any relevance, or if this is normal/abnormal:

I wanted to replace my end-links on the car because I suspected one of them (the front right) was damaged - whenever I drive over bumps, I hear a nice thump louder than the rest on the front right of the car.

I wanted to replace all of them because I didn't want to use OEM end-links. I started by replacing the rears first, as those were easier for me to access. I was trying to take the rear-left one off, and the nut holding it to the car (not the swaybar end) was impossibly tight and I stripped it.

So I proceeded to try to take the sway-bar end off. I successfully got that end off, and immediately the end-link suddenly had a lot of free play. Long story short, the pivot point of the end-link that was still connected to the bar came out of the end-link slot. I'll try to take pictures tomorrow (I still have the broken end-link in my trunk).

I don't know why this happened. The stock end-link pivots felt extremely stiff. I don't know if it is normal for it to be so stiff (barely could move the pivots around). I could only attribute it to age and corrosion (the nuts were rusted onto the screw ends of the end-links).

EricMeyer 01-26-2010 06:09 AM

Let's revisit this. Swaybar end links CAN and DO affect your suspension's alignment. You or your alignment shop may/will/can still obtain your target camber and toe settings. These are generally a little negative camber all the way around, a little toe out in the front and a little toe in the rear as most of us know. The main difference is the pre-load in the suspension. Pre-load is a state of tension. It has energy in it. Examples include: a boxer or karate guy all twisted up and ready to unload a big punch on someone, your golf backswing before you address the ball, pulling a rubber band and holding it and taking a hollow metal bar about as thick as your finger and 3 feet long and twisting it while holding one end steady--perhaps in a vice. All of these things have stored energy. Do I sound like your 8th grade science teacher yet?

The last example above was obviously a car's swaybar. The twist or tension comes from connecting the swaybar end link's which confirm or hold that tension in your car's suspension system. Normally (in my experience) this comes from when people purchase new end links and install them. Generally 1st timers and people who have yet to learn the correct way do it like all of us once did. I use to do it until someone showed me. This post is for you who have yet to learn.

When we jack up one side of the car to get to these endlinks, as most people do, one side of the suspension is compressed while the other (the one up in the air) hangs down. Typically people refer to the one side as "under compression" or compressed and the other side as hanging or "under droop". There is tension in the suspension at this point. When you install your endlinks you are retaining or holding in this tension. Congrats---you are normal. Normal because most of us don't have another option. The correct way would be to disconnect one of your endlinks (you need only disconnect one to remove tension or pre-load from your system), align your car (remember to substitute something for your body weight in the car), set camber, toe, cross and sometimes caster and then reconnect these endlinks (front and rear). You would connect these so that they are very lightly attached. This means that you can tighten the nuts on the endlinks as much as you want but do NOT pull or tighten the length between your swaybar and its connection. For the front his would be the distance of swaybar end with the hole in it to tab on the front lower control arm. And then the end of the rear swaybar with the hole in it to the welded mounting tab bracket on one of the rear lower control arms in the rear.

If you do perform this method (jacking up the side of the car to replace the links ) you must certainly will have contained preload in your suspension system. This can be just in the front or rear or both. This could be a none, a little or a lot.

So picture this. Your car is sitting in the driveway yet the car has a bunch of tension in one or both of the swaybars. They are "twisted" and contain a force within them. This makes the car do wacky stuff as the suspension moves. Generally you wouldn't notice this when driving like your Aunt Matilda to the grocery store and back. The more you use your suspension (like Auto-X or Open track driving) the more this pre-load comes into play and influences the mechanics when your suspension moves. As a general rule this influence is not favorable and your new alignment (or your old alignment with your new end-links installed) impairs its natural ability to work.

So how the Sam Hill do you prevent this? One thing you can do is ask your suspension guys (or better yet tell them) to disconnect one endlink (to remove any tension), do the alignment and simply reattach the end link. Or for the DIY guys raise your entire car off the ground (remember to use a very, very flat and level surface) with equal height above the ground, remove your stock end links and add your new ones. You should be able to grab all found end links in the middle of the link and rattle or jiggle them. This would indicate no preload. You could do this several ways. Most DIY guys that I know in the club racing environment purchase some 2" x 10" or 2" x 12" boards from Lowes or 84 lumber or wherever, cut them down to 1 or 2 foot lengths, stack them up or nail them together and then jack up each side of the and work or step up each side of the car until you can get under it. May I suggest that your emergency brake should be used and the more level the ground the less likely the car tends to roll off and sever your head/legs/arm/other. Raising your car 12" or so equally off the ground is about all you need. Do this anytime your align your car or have it aligned, change your ride height or really anytime you adjust anything in your suspension. Stock end links allow you do to this. Ideally the more vertical your end link is the better it operates as the rate of change in your bar will be more linear. In otherwords if you make your own links (which is really easy to do and a little cheaper than some of the pricepoints you can buy in the market today) but be careful not to make them so short or so long that 2" of suspension travel doesn't result in 1" or 4" of bar movement. A good guide is the approximate length of the stock endlinks or slightly different in you significantly raise or lower your car.

One day I am going to make a video on this but for now this will have to suffice.

Happy rotoring.

Eric

JinDesu 01-26-2010 06:57 AM

I did mine on a car lift - (the rear's anyways) - because I needed the shop help to remove the stock bits that were pretty much rusted to the car.

However, as a DIY-er in general, will raising only the rear or the front cause preload the the raised side? What I mean is, jacking up the right, setting a jackstand, then jacking up the left, and setting a jackstand of equal height. Is this sufficient to work on the bit of the car that is in the air, or must all 4 wheels be off the ground level to ensure the proper end-link connections?

Spin9k 01-26-2010 07:04 AM

I think one way to avoid some of this problem when messing w/endlink length is to use the factory lift point frnt and rear - both are on car center...the diff in back, the center crossmember jack point in front...using a suitable 2 ton or better lift jack on level floor.

Personally to remove preload I use one adjustable link at the frontr and one at the rear to compensate for the corner balancing height offsets. As both sides go up together, preload doesn't change much, if at all.

TeamRX8 01-26-2010 09:40 AM

Seriously, some people make everything more difficult than it needs to be.

I've always been able to get the OE links to work without preload, even cornerweighted. By having all four endlink nuts/axle loose you gain the slop of each hole x 4. This has always proven to be adequate for me to get the OE endlinks to fit without binding after the car is settled/cornerweighted/aligned.

JinDesu 01-26-2010 09:50 PM

Just to put up the pics I promised before of my rear endlinks:

https://i97.photobucket.com/albums/l...u/DSCI0081.jpg
https://i97.photobucket.com/albums/l...u/DSCI0082.jpg

Each of those joints are RIDICULOUSLY hard to move. If it wasn't for the fact that I know they are pivot points, I might have thought they were supposed to be stiff like that.

burglar 01-31-2010 10:46 AM


Originally Posted by Spin9k (Post 3390871)
Did you ever verify your rear sway wasn't installed upside down (the common mistake)? The most likely answer since you don't know the car's history and truth is your more likely to be hit by a meteorite than have 2 endlinks on the rear break only a couple months apart on the same car for no good reason.

If you don't fix the source of the problem, whatever it is, the failures will just continue...

Well, I replaced the endlink yesterday. I'm pretty sure the bar in on correctly - there is a distinctive "V" in the bar that goes over the exhaust, if the bar were upside down it would point somewhat down and to the rear.

I also verified that my bar rotates freely in the mounts.

The other end of the one that just broke also popped off in my hand while trying to get it off. I'm pretty sure my endlinks were just really weak. What a silly design.

Spin9k 01-31-2010 11:04 AM


Originally Posted by burglar (Post 3410108)
Well, I replaced the endlink yesterday. I'm pretty sure the bar in on correctly - there is a distinctive "V" in the bar that goes over the exhaust, if the bar were upside down it would point somewhat down and to the rear.

I also verified that my bar rotates freely in the mounts.

The other end of the one that just broke also popped off in my hand while trying to get it off. I'm pretty sure my endlinks were just really weak. What a silly design.

...easy way to tell is study the pics of a bar installed wrong and installed right in this thread...

https://www.rx8club.com/showthread.p...ht=Racing+beat

2nd post pics 3 and 4 show the examples. See the 'kink' pointing up (wrong) and pointing down (right) atfter the 90deg bend and before connecting to the endlink.?

TeamRX8 01-31-2010 03:20 PM

The endlinks have survived tons of abuse on may applications without breaking

you just have a bad set, as long as the bar is correct per your previous post then install a new pair and go about you business :dunno:

TeamRX8 01-31-2010 03:37 PM

It's also possible to install the front endlinks backwards which will cause them to break too. The rear endlinks can go on other side, but the front links have dedicated left and right configurations that can be installed on the wrong side if you're not paying attention

elysium19 01-31-2010 10:46 PM


Originally Posted by TeamRX8 (Post 3410507)
It's also possible to install the front endlinks backwards which will cause them to break too. The rear endlinks can go on other side, but the front links have dedicated left and right configurations that can be installed on the wrong side if you're not paying attention

Team - the OEM ones are left and right sided? Or just some aftermarket ones? I never compared them directly....but still, never noticed this before.

TeamRX8 02-01-2010 02:19 AM

The OEM ones. The bottom stud points forward and the upper stud inward. So they are obviously opposite of each other. On a heim joint end link you can turn stud to point either direction, but you still have to point the bottom stud forward. In either case if you mount them so the bottom stud is pointed rearward it will bind until something eventually breaks or bends.


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