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Need a doctor to diagnose my suspension problem

2677 Views 17 Replies 9 Participants Last post by  Teachmehowto20
So I recently purchased BC coilovers with offset topmounts. I lowered my car another inch and a half from when I had my Ksports. I do not have pictures right now but it was decently low. The first ride in it I hit a small bump and heard a hard knock and the impact was hard. I first thought it was my shocks in the coils bottoming out but that wasn't the case. The threads are maxed out for lowness, and I did not mess with preload. The coils are settled now and still every little bump I have to deal with the hard hitting over them. Ican not figure out what the problem is. At first I thought it was the UCAs hitting the UCA bracket area (considering when you lower the car, all of the suspension components move upwards toward the top of the inner fender area/less suspension travel) but I can't find any marks of hitting any places. The tophat nuts are tightened again also. Any help would be appreciated. I do not want to buy things I don't need. I had to raise my car again till I figure it out. I just don't understand how most people run very very low with stock suspension components and no hitting issues. Help me out please!
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Disassemble and inspect. It should be obvious.
Im guessing some 3rd smack down... pull wheel off and jack arm up to ride height and check everything out man..
Probably. Pull the spring off and while you're in there look at the body on the shock would hit inside the 3rd link. If it's not obvious put it all back together and move it through it's range and see what's hitting.
I raised it back up an inch and a half and NOW it's third link rubbing. I'm used to that annoying noise. But the third link noise sounds like two taps. This is like a clunk/knock and it feels as if there's no suspension travel when it hits. Like it feels as if I'm bottoming out...but I'm not? It's weird. I've checked the coils and there's no sign of wear or hitting. Could it be something other than the coilovers itself?
The dreaded "clunk" was the UCA's hitting the strut tower. It doesn't have much clearance from where it sits to the point it hits on the strut tower. I have seen a few cars lower than me...so does that mean they were running different UCAs? And would a stiffer spring rate help the problem? It doesn't do it anymore now, only if there's added weight to the car (i.e. a person) or if I am alone and hit a big bump or pothole. Any help would be nice.
Am I still the only one having issues with the UCAs hitting? WHat spring rates are everyone using with their BCs????
I had the same noise with all mysetups only on my left side a lot. With the stech's less with the H&R , mush less with the SS and BC's. But I gave uo trying to find why , as u said it sounds like the shock is bottomomg out but it isn't that beacuse when I inspected the bump stops on the SS they showed little contact marks. Ijust gave up trying to find it . Changed uca's , third link modified and even took the roll bar links off. Noise is still there more so with weight. So it may be the arms at full travel. I just gave up
cusco or dmsentras upper control arms are shorter adjusting the camber and may give u more clearance
sounds liek you may want to run stiffer springs.
The stiffer the spring the less everything is gonna move.
Go like 20k and see what happens.
sounds liek you may want to run stiffer springs.
The stiffer the spring the less everything is gonna move.
Go like 20k and see what happens.
You kinda came close with this , After i read this comment , it never left my head. Last week i decided to raise the ride hide of my car at front and i did so by raising the preload instead of the height adjustment itself. I added 5mm more of preload to the BC's and after that the noise is gone , rides stiffer but noise free. higher preload acts like higher spring rate .
There is a mod that UNISA JECS did to his third links, which made a little more room for the coilovers to move. It involves grinding metal to make more room...
There is a mod that UNISA JECS did to his third links, which made a little more room for the coilovers to move. It involves grinding metal to make more room...
Did that as well, that's not the same noise tho
You kinda came close with this , After i read this comment , it never left my head. Last week i decided to raise the ride hide of my car at front and i did so by raising the preload instead of the height adjustment itself. I added 5mm more of preload to the BC's and after that the noise is gone , rides stiffer but noise free. higher preload acts like higher spring rate .

Can you explain what you mean here? compressing the spring (adding preload) doesnt make the ride stiffer, it changes the dynamics of the damper (where the piston is and how much weight before things atrt moving etc) so the stiffer feel you may get isnt actually the same thing as increasing your spring rates. Its more like requiring the car to need more weight before compressing the spring.
Ok sorry for my poor choice of words. When I added to the preload the ride quality presented itself in a more rigid from. I had to lower my shock adjustment from harder to softer. From 20 to 10. But you explained it well for me thank you lol. And it definitely stopped the noise I had on my left side. Car feels very stable also
Ahhh ok, yea because preload wont affect the weight, but it will CERTAINLY effect the overall ride feel. Greatly too.
I used to have "hand-tight" preload, and my car really felt like crap. So finally i decided i would go to the recommended 5mm, that alone made my shocks ride soooo much better.
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