Car Makes me Bounce UNCONTROLLABLY!

[Murdastylez15]

Hi all,

Ok, so when I'm driving at all times my car makes me bounce like crazy. It's embarrassing and uncomfortable . I have the K-sport coilovers made for the mx-3 installed. I know the springs are stiff but is it possible that my springs are too compressed? Or is there something else I'm missing? Any suggestions would be helpful.

Thanks.

[MrMazda92]

Did this come on all of a sudden, or immediately after the coilover install?

[mazda915]

if u didnt preload it properly then yes u will be super bouncy and as well as stress ur coilover's bad.... as well as popping em . preload is when the spring is able to move around by hand and where the lockers are not forcing the spring up or compressing it to much . if u cant twist the spring freely wit ur hand his when locks are in place then yes ur preload is to tight and thats where u have that excesive bounce . i had the same problem then visited ksport in az in gilbert and they showed me how to properly preload it and have it safe , i had to raise the car a little to have it where i wanted it and as well as the preload is perfect .

[Josh]

Also check your dampening. My car was bouncing all over the place as well when I got it and it was because the coils were set at the lightest setting. It was just too light for the springs, so once I set the dampening, it now rebounds like a champ, no bouncy bouncy... I hate that feeling. They are 12 way adjustable, and I ended up going 6 clicks up front and 4 in the rear to find a good tolerable setting

[youdirtyfox]

Also check your dampening. My car was bouncing all over the place as well when I got it and it was because the coils were set at the lightest setting. It was just too light for the springs, so once I set the dampening, it now rebounds like a champ, no bouncy bouncy... I hate that feeling. They are 12 way adjustable, and I ended up going 6 clicks up front and 4 in the rear to find a good tolerable setting

This^ clicked mine recently to normal setting after being on the lightest and the bouncey bounce is all but gone.

@mazda915 could you explain what preload set up you were shown please?!

[wytbishop]

Just to clarify: Springs 101...

The spring is the part that actually suspends the weight of the car. It's no different than any other spring except that it's stiffer and sometimes they are progressive which means that as it is compressed more and more force is required to compress it further.

Preload is the amount of force put on the spring in the normal ride height position...i.e. before the suspension has experienced any travel. Preloading is done to get a progressive spring to the point in its compression where the desired force is required to compress it further. For a racing application where the track is smooth but there is a lot of hard cornering, you would preload the spring more because you want the suspension to be quite hard to compress to reduce roll in the corners. On a rough course or city streets you would rather have a little softer spring so that less force is required to compress the spring and the roughness can be absorbed more easily.

A spring is a very simple device. If you push on it, it pushes back with the same force. And it has the same rate (usually) whether it's being compressed or expanded. A spring that is uncontrolled will just continuously compress and expand until the energy that acted on it is dissipated. That's why K-sports and others have dampers. Higher end systems have dampers for rebound and compression. The damper is just two reservoirs separated by a small orifice. Fluid is forced through the orifice from one reservoir to the other as the shock is compressed and then it flows back when it retracts. The spring is still doing the work of suspending the car, but the damper prevents the spring from expending all its energy in either direction. Really techie shocks have dynamically variable orifices that are controlled electronically.

On it's lower settings the rebound damping orifice is large and isn't having much affect on the spring so it will extend almost as hard as it was compressed. The hard expansion of the spring will throw the weight of the car back up and it will come down and compress the spring again...and so on until the energy is dissipated.

If the rebound damper is set too high, the spring will not be able to decompress quickly enough and when you get to the next bump the spring will still be compressed from the last bump causing the car to bottom out hard.

So that's just the basics of how a shock works and some of the lingo. Mostly because I'm bored at work. I hope that clears up a question or two.

[Josh]

The small spring here is the preload spring.



One of the reasons I dislike just Ground Control setups, so I added H&R preloads.

[mazda915]

hope u got ur suspension nice and treaked but wytbishop and josh did a great job of explaining more and showing pics !

[wytbishop]

The small spring here is the preload spring.



One of the reasons I dislike just Ground Control setups, so I added H&R preloads.

That's an interesting way of doing it. I assume that the proload springs are available in a range of spring rates and can be changed to increase or decrease the proload on the main spring.

[Murdastylez15]

Tons of information. I really appreciate the words of wisdom here.

I will have to read up more on dampening and preloading. I tried to cheat by loosening my springs while they were still on my car...FAIL. On my front camber plates there’s a dial that states Soft to Hard. I can turn the dial left for Soft and turn right for Hard, is this the same as dampening? If so, what other options of dampening do I have with this set?

The small spring here is the preload spring.



One of the reasons I dislike just Ground Control setups, so I added H&R preloads.

Also, it’s hard to tell what’s going on in this preloading photo. Could you please explain a little more. Could I have a link for those preload springs please?

[wytbishop]

If you look at the the thickness of the material you'll see that the top spring in the photo is a smaller gauge of steel which makes it a softer spring. I'm not totally familiar with that particular setup but it looks like the helper spring on top, which is much more easily compressed than the actual suspension spring, is being used to put some pressure on the lower spring. The stiffer the helper spring you use, the more it will compress and preload the main spring.

This type of set up would also prevent the spring from totally unseating from the top perch when the suspension is totally unweighted. The helper spring will extend to take up the slack if the suspension is totally extended.

[Evo_Spec]

Tons of information. I really appreciate the words of wisdom here.

I will have to read up more on dampening and preloading. I tried to cheat by loosening my springs while they were still on my car...FAIL. On my front camber plates there’s a dial that states Soft to Hard. I can turn the dial left for Soft and turn right for Hard, is this the same as dampening? If so, what other options of dampening do I have with this set?

soft will let your dampers move "quicker" and hard won't, right now your dampers are probably set all the way soft or close to all the way, try turning them a couple clicks to hard and see what happens

[Josh]

exactly what wytbishop said.

here is a decent article i came across that might help explain it http://e30m3project.com/e30m3performanc ... /index.htm

The preload (or also called helper springs) spring in my case is supposed to be fully compressed under load. From what i found when searching for them is there are a few types depending on what your set up. these are like 50lb or 80lb springs (i dont remember for sure i will have to look it up again). But their main purpose in life is to keep tension on the main spring "preloading the suspension" to keep the spring in its perch at all time.

H&R says this about them:
"They can either increase the rebound travel or the response of the spring system, depending on whether the helper springs are already closed and have more travel, or if they can still influence the rate of the chosen main spring. To harmonize the intersection of the main and helper spring there are also four different kinds of progressive helper springs on stock"

From the sounds of it your dampening (the stiffness settings) are on soft. I would try adjusting them a quarter or half way stiff and see if it makes a difference like Evo_Spec said. I would run a little stiffer in the front from the rear due to heaver spring rates and more weight in the front. But I would start to play with them a little

Have fun and let us know the outcome

[Murdastylez15]

Thanks alot guys for giving me this information. I'll absolutely let you all know what helps me. All the bouncing is enough to make you sick.

[Murdastylez15]

Update:

I preloaded my springs over the weekend. My car has not been bouncing uncontrollably anymore. The ride is smoother and my sterring even feels tighter, though I do need an alignment now. But in the end, I am very happy with the way this fix turned out. Thank you guys for helping me out. This was the fix to my problem defnitely.