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Old 04-22-2012, 11:38 PM   #1
banifesto
 
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Unhappy Coilovers settings tip - reduce bounciness?

Hi folks,

I got a BC coilovers, which I believe it is the same as Megan, etc.

For the fronts, I increased the height a little bit so that the wheel gaps are even with the rears.

Rears are left untouched, basically installed without adjusting anything.

At first the ride is somewhat bouncy, so I instructed the installer to increase the front springs preload to 5mm. This really helps on reducing the bounciness greatly.

After the coilovers have settled in, I can still feel a slight hint of bounciness, especially on low speeds (start-stop traffic) even on a smooth road. The bounce is subtle, but enough to get me nauseated.

A friend took a ride and he commented that the bounce feels unsettled. I've tried all damper settings (full soft, medium, full hard). The bounce becomes more apparent if I set the damper to be more stiff. At 10 clicks or lower, the bounce is acceptable but I'd like to make it perfect.

Any tips to get the best out of the coilovers? Bumpy is fine. I like a firm ride. I'm very sure the unsettled bounce feeling can be eliminated.

The bounciness is felt on the fronts, but who knows, it may be caused by the rears?

Should I adjust the rear springs preload? or increase the front preload to 10mm (close to 1/2 inch). Any inputs are very much appreciated!
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Old 04-23-2012, 12:35 AM   #2
Kaotic Lazagna
 
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General rule is to never touch pre-load and adjust via shock length adjustment. Then set dampening to your liking. My friend's 8th gen Civic is much lower than my Vios (he's on BC coilovers and I'm on Tein springs/TRD dampers), and his car rides smoother than mine.

http://www.rx7club.com/showthread.php?t=600868

http://legacygt.com/forums/showthrea...s-181610.html?
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Old 04-23-2012, 02:31 AM   #3
banifesto
 
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Thx Kaotic.

I did the preload adjustment as per recommended by BC. The fronts seem to be better after the adjustment. I haven't touch the rears as they are more tricky to adjust.

Ride height is fine at the moment. Just that tiny bit of unsettled bounce.
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Old 04-23-2012, 02:40 AM   #4
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NP.

I'd try it the general way of adjusting coilovers. See how it works out. What's your dampening set to?

Oh, and when I said BC earlier, I meant Buddy Club. haha
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Old 04-23-2012, 09:13 PM   #5
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Bounciness = inadequate damping. Increase your rebound damping to control the springs.
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Old 04-23-2012, 10:23 PM   #6
banifesto
 
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dampers set to 8 / 5 (from soft) for fronts and rears respectively.. smooth but too soft. the installer added more preload, subtle bounce seems to be gone but it also introduced a new way kind of bounce.. hard to explain but i think the front springs are too tight lol! too much preload methinks.

very contrast to the rears as they feel sharp without excessive bounce on whatever damping i put on.

i'll reset the preload back to 0 (so the springs are just snug with the perches) and adjust the damping appropriately. if the subtle bounce is back, i'll just add a little preload, maybe 3mm to see if it helps.

also, do coilovers need time to settle in?
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Old 04-23-2012, 11:13 PM   #7
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You should never need preload, that is only an option because those shocks were not built properly for the application. A lot of these places buy shock bodies that have a range of length that will fit a dozen or more cars and then add hardware to fit a particular application, that is the only reason they have the additional height adjustment.


Sounds like you might be hitting the bump stop prematurely, or you may not have enough droop, check your travel.
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Last edited by Jason@SportsCar; 04-23-2012 at 11:35 PM.
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Old 04-24-2012, 09:20 PM   #8
banifesto
 
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Thumbs up

just redid the front springs all over again.. eased off the tension and retighten as per recommended by the tech support. bounce is nearly gone. all good now, just a matter of adjusting the damping. all DIY and the feeling is

adding more preload will just increases the height.. and too much preload is bad.
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