Heya folks, I was wondering if some folks could help answer me some suspension related questions.

I have recently fitted D2 Coilovers + LCA's on my EM1. I have left the preload as set by the factory and lowered the car so that there is around 40mm thread left on the body of the coilover. The compression/rebound setting is currently at 3.

Righty, the problem is the ride is extremely harsh on 6 (as you would expect) but also really bouncy. You feel like you are being chucked up and down in your seat. If you are unlucky enough to find a few bumps in succession this sends the car crazy.

I have had a friend behind me who also commented on how bouncy the ride looked.

Obviously it's a coilover kit, It ain't ever gonna ride like stock, but to be honest I didn't expect to be buying a trampoline either.

So, I'm trying to sort this out which got me thinking. Could it be :

1) Bad camber ? What sort of effects does this have on ride quality ?
2) Worn bushes (granted the guy who fitted the coilovers said they were ok) but whats the signs of worn bushes ?
3) Tyre Pressures (running 32psi all round on 205/45 T1 R Proxies 16" Rim) Worth lowering ?

I spoke to the company that sold me the coilovers and they said the spring rate they sent with the coilovers was standard for my type of car (I.e. no problems with it normally) however I have misplaced the bit of paper with the spring rates on em.

So folks what do we think ? I have tried most of the settings on the coilovers I can think of, they do get stiffer when you adjust them and they do not appear to be blown, so what the hell is going on ? All I am looking for is a stiff ride that does not bounce all over the damn place !

Drop me a line folks I'm struggling here !

- Prob

 

get used to it.. suspension wasnt made for highway use, best of luck

 

i gotta go with crxboyy408 on this one, get use to it cause its never the same

 

Like I said I know it will be different, and have driven several cars with coilover suspension fitted before this one. What I am saying is it feels like something is broken or installed incorrectly.

What I am looking for is for someone to answer the questions above so I can determine what (if anything) is broken/Installed incorrectly. Or better still for someone else to throw something new into the pot that I could look at.

Cheers,

- Prob

 

Hint: $100 says the factory didn't "set" any preload.
How far is the car lowered? 40mm of thread left on the shock body is not a good way to estimate ride height, due to both the lower mount and spring perches both being adjustable; since neither is fixed, height can vary significantly from side to side if you just look at the threads.
If the car is too low, your ride will be very harsh, because you've reduced shock travel (the distance the piston has to travel before bottoming out), and you might be riding on the bumpstop(s). So with very little shock travel, it won't take much to bottom out the suspension.
Tire pressure and bushings will soak up high frequency motions, but AFAIK not the sort of stuff you're talking about. While its never good to run around on busted bushings and too high/too low tire pressures, I don't think its causing you problems. Camber will not cause these problems either.
Are you sure you installed them on their appropriate ends (fronts on the front, rears in the rear)? Weight is not distributed equally front and rear, so valving is (usually) different between fronts and rears. Try and find what spring rates you've got.

 

Hey there,

Finally a post worth reading

Well, I am still working on the spring rates, The pre-load is around 5mm (I.e. the spring was 180mm un-compressed and is now 175mm) as for lowering, not very scientific I know but I can get two fingers between the wheel and the arch (around 30mm).

The coilover is adjustable for preload and ride heigh independantly. The car isn't insanly low. Just lower than stock.

The coilovers are definatly installed correctly. I don't *think* I'm riding on bump stops (I don't hear any crashing noises or anything to suggest I am) but I may be wrong.

I have clunking noise from the one side but this sounds like the anti roll bar uplink (had one fail before) so Im hoping I'm right.

Sorry for the lack of detail, I hope this helps a bit. Thanks for your input !

- Prob

 

excessive positive caster can cause a rough ride. but keep in mind the strut controls the springs from making the car bouncy. i would assume the strut is defective. just my 2 cents

 

I have heard a failed strut could cause this ride problem also, but as there is nothing to suggest a strut is blown (no leaking fluid, adjustability works fine) that combined with the fact that the strut had done less than 2,000 Miles leads me to believe something else is responsible.

Cheers,

- Prob

 

Just found out, front springs are 11kg/mm and rears are 5kg/mm.

Any ideas folks ?

- Prob

 

Sounds like your shock is resisting to compress, which means it won't absorb the shock, and the rebound is high and forcing the car back up quickly. I believe you want the bound to be softer, and the rebound stronger, because it has to push the car back up to its normal height after a shock is compressed. Your kg/mm ratio sounds pretty extreme too for a Civic. 11 front, 5 rear? Your front is like double that of your rear. Didn't those come with 3 sets of springs? Like an 11, an 8, and a 5? and you are to decide whether to put in 8 and 5, or 11 and 8. I forget if D2's were the brand that was sold like that. One of those off brands sells them like that. I was seriously thinking about picking up some of those D2s also...hmm.

 

did you try lowering the dampening? i dont believe you mentioned that. on my EG with ITR flex suspension, with the dampening in the higher levels of dampening its similar to the ride you are describing. when i turn it down to the lower areas the ride is WAY more tolerable. i DD this car, when the dampening is hard the 10 mile ride to work is difficult.. so try that cause it seems like you didnt mention anything about that.

 

Hey,

I had that same problem when I bought my Koni Yellows/GC Coils... I would be embarassed to drive girls around cause it was so bouncy, uncomfortable for them you know? But I switched to Tein SS's and it rides like stock! It's lowered too, I have no wheel gap. I'm loving them right now, so I dont know whats wrong with your D2's, but when I got my koni's, they just happened to be like that, while other poeple said their koni's were just fine, I'd think their crazy. Something is probably wrong with the shock, I'm guessing. If anything it's suppose to be stiffer than stock, not bouncier, as you mentioned trampoline bounce.

Sorry if I'm not of any help, just letting you know what I had. Goodluck to you

 

Heya folks,

Well, it's been an interesting few weeks of trial and error, what I can report is that a problem with the rear anti roll bar problem was causing a lot of problems. Essentially it was binding on the one side. This binding was demonstrated by when one wheel hit a bump the car was ok, when both hit a bump the car was thrown into the air on one side.

The best way I can think to describe it is that there was too much load on the spring caused by the bar binding on the one side. I replaced the uplink and took the same bump I knew to cause a problem and the effect was dramatically reduced.

As for compression/rebound dampening, I adjusted the ride height again (approximatly 30mm between the top of the tyre and the wheel arch) then reset all the compression/rebound settings and started over.

As mentioned by ej0513 the dampening was too harsh, I worked my way up from 0 and got to 3 by which point the car understeered heavily, 2 all round seems to be the best setup, the ride is now quite harsh but ultimatly not bouncy and also has a nice amount of predictable lift off over steer.

I am hoping that by adjusting the camber correctly I can reduce the sharpness of the ride but we will see. At the moment at least the ride is bearable and the handling much more consistent.

As for the spring rates, well, I am told those are the best spring rates for my setup, I have spoke to numerous people with a similar setup and told they experience no adverse effects running those spring rates.

I shall carry on with it as it is at the moment and if it truely does become unberable I may get some lesser spring rates just to see what gives.

kings1ey what rate are the springs on your tein's ? I'm just curious, I have heard a number of folks say the teins are soft for coilovers.

I'd just like to say thanks to all you folks for your help, nice to know how everyone else is dealing with this sort of stuff

Speak to you all soon,

- Probs

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by DjGuamstyles &raquo;</TD></TR><TR><TD CLASS="quote">Sounds like your shock is resisting to compress, which means it won't absorb the shock, and the rebound is high and forcing the car back up quickly. I believe you want the bound to be softer, and the rebound stronger, because it has to push the car back up to its normal height after a shock is compressed. Your kg/mm ratio sounds pretty extreme too for a Civic. 11 front, 5 rear? Your front is like double that of your rear. Didn't those come with 3 sets of springs? Like an 11, an 8, and a 5? and you are to decide whether to put in 8 and 5, or 11 and 8. I forget if D2's were the brand that was sold like that. One of those off brands sells them like that. I was seriously thinking about picking up some of those D2s also...hmm.</TD></TR></TABLE>
When talking about rebound and compression damping, we mean how resistant the shock is to either rebound (returning to its regular length) and compression (being pushed down).
If the rebound was high, it would not "force" the car upwards, as the only thing that pushes the car back upwards is the spring.
Typically rebound is set to be roughly 2-3x higher than compression. The spring rate is nothing extreme for a Civic at all. The purpose of the large front bias is ride comfort, with the sacrifice of performance.

To the OP: can you explain how the bar was binding like you say? I am having trouble picturing it.
With such a spring combination, I'm not surprised that the car understeers heavily. While there's a few other factors that may contribute to understeer, the most glaring one would be the big difference between front and rear spring rates. Camber will do nothing noticeable to ride quality.