What's the deal with sway bar endlinks?
 

I bought the Eibach sway bar kit (25mm front, approx 3x stiffer; 19mm rear, approx 1.25x stiffer) and just trying to figure out what I should do about the endlinks.

Eibach's website cites using OE endlinks for both front and rear, but I'm not sure.
I feel like OE endlinks will quickly be overstressed, but maybe not?

What's the deal with adjustable endlinks? I understand they can adjust pre-load on the swaybars, which is great for dialing-in on the track, but I'm not experienced enough to utilize that option. I also see they may help with installation, but that's kinda minor.

Also, some of the prices vary wildly. Some adjustable endlinks are ~$120, while others are over $250.
Obviously the static endlinks are cheapest at just under $100, but then why wouldn't I just buy OE stuff for $15 ea?

Aftermarket links are not "necessary" when installing aftermarket sway bars.

Their use typically comes into play when the ride height is substantially changed. The goal is to NOT have preload on the sway bars and this is where adjusting the length of the link is needed.

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I am certain that a solid 25mm swaybar will bust a stock endlink eventually. I replaced my endlinks with Perrin non-adjustable because I couldn't believe how frail they seemed.

That's just me future proofing myself, but I honestly think aftermarket endlinks are good peace of mind.

I've had a 24/18 combo on otherwise stock setup (including links) for going on 7 years now, and no issues. As mentioned, adjustable links are to make sure there's no preload, as well as adjusting length on lowered cars.

https://racerxfabrication.com/frs-br...ront-end-links

Both front and rear on sale now. Very nice sturdy pieces.

Eibach end links are not adjustable on the car (unless they’ve redesigned them). You have to unbolt them to make adjustments, which in my opinion makes them useless.

As noted, they are primarily used after height adjustments. A couple of years after lowering my stock links began to knock and clank while turning and going over bumps.

Ok gotcha. Thanks. That makes sense as the Perrin non-adjustable type said they were slightly longer than stock to accommodate lowered vehicles.
Seemed not applicable to me since I'm currently stock height, and vague otherwise as someone might be lowered 1", and someone else might be 2.5".

So just to spell it out: you're saying a car should have approximately zero preload when sitting on the ground, not moving?
Like if you found a way to remove the sway bar without jacking the car up, there would be zero tension on the endlinks, and the bolt would just slip right out of the swaybar eyelet?

I know this is somewhat of an idealization, but I'm not sure I agree with it. My initial intuition would be there should be some level of preload, just like your struts.

sway bars are not solid. They are tubular. 25mm solid sway bar would be insane.
I think 22mm is like the max that is typically available aftermarket. I don't remember the math, but I believe the 25mm hollow is comparable to the 22mm solid.

Aside from this, the rest of your reply is simple conjecture.
Thank you for this. That is quite a good deal. I did not see those before.

@Stomachbuzz yes, there should be zero preload on your sway bars. Any preload and the sway bar will act like additional spring rate......like a massive progressive rate spring.

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The sway bar arm needs to flat (parallel with the body of the car).

When you have multiple adjustment points on the bar arm, you need to lengthen/shorten the endlink so the bar stays flat. For example, the bar arms may be flat on the soft setting, but the stiff setting is closer to the bar itself, so you’ll need to shorten the endlink to make sure you keep the bar arm flat when using the stiff setting.

Worse, it changes the corner weighting too.

Correct [emoji817]

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Those are the sway bars that come with the SCCA autocross Solo Spec Coupe kit, along with Eibach springs and some other suspension parts. It requires stock end links, so it is definitely an option. I've used them for 2 years without any real signs of wear or additional noise (though I check/tighten the front endlinks frequently).

With that said, the end links are extremely bound when used with that kit, especially if you use the soft setting with the rear bar.

can you guys verify that i installed my adjustable endlinks wrong? pretty sure i did.

i installed coils today. they came w front endlinks. after the coils were on, i started with the endlinks as small as possible, and extended them slowly until they slid into their mounting holes, ill call that "neutral" i torqued the endlink mounting nuts to spec.

then i think i went wrong. with endlinks installed with the wheel off, up on stands, i them tightened the endlinks by rotating the center rod, making the endlinks shorter by ~.5 inch on either end of the rotating rod, making the entire endlink ~1in shorter. i thought the neutral position meant they were loose. (i just learned now that i "preloaded" the sway bar by doing this. then i cinched down the lock nuts to the rotating rod.

im finding out now that i should have the wheel on the car, resting on the ground, then get the endlinks to "neutral" then set the lock nuts. the sway bar arms should be ~parellel to the ground.

can you verify that i f'ed up. and do i need to change it immediately, or is it whatever bc i just DD. tia.

The car needs to be on the ground when adjusting the end links to get zero preload. I'd fix it.