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View Full Version : Bouncy coilovers...


todd5854
12-27-2012, 09:44 PM
I've had function and form type II on my s13 vert for a few months now..

My extremely biased friend told me they're bouncy pieces of shit. My other friend who owns them on his s14 says they're fine.

Would getting a stiffer rear sway bar improve my rear rigidity? Or do I have to tighten the pre-load a bit? I see tons of guides on how to do these tasks, but not much on how to tune them for the car..

Banana_Cute
12-27-2012, 10:03 PM
believe it or not, not everyone knows how to adjust coilovers.

Maybe your friends who thinks their bouncy as shit dropped his car via collars and not the seat tube. If you lower it via collars you decrease the amount travel of the shock.

I for one thought Ksport were a shitty coils, until I got under my friends car and adjust it properly for him. they're not that bad for the price.

todd5854
12-27-2012, 10:39 PM
I loosened the collar, and lowered it on the entire tube. I didnt even touch the preload.

Although I seem to be reading that you want to be able to turn the rear springs, but have no vertical play.. mine are so tight you need two hands to turn them. Should I fix that and see how they ride?

todd5854
12-28-2012, 02:14 PM
Update..

Fixed the bounce, they're tight now! As they should be.

One more problem.

If I turn the steering wheel left and then right really fast, the rear kind of just floats there. As I raised the rears a little bit it wasn't as bad. The car was slammed to the ground when I first installed these and the floating was awful.

What can I do to stop this from happening?

Ltkouki
12-28-2012, 04:45 PM
Update..

Fixed the bounce, they're tight now! As they should be.

One more problem.

If I turn the steering wheel left and then right really fast, the rear kind of just floats there. As I raised the rears a little bit it wasn't as bad. The car was slammed to the ground when I first installed these and the floating was awful.

What can I do to stop this from happening?

It sounds like you dropped the spring instead of lowering the cartridge

todd5854
12-28-2012, 09:33 PM
Another update...

No idea what actually happened, this car rides like total shit on the highway. If I put force downward on the car to make it bounce, the front comes back up and remains stiff.

The rear bounces once then goes back. Why would this happen?

Driftwurks
12-28-2012, 09:41 PM
Another update...

No idea what actually happened, this car rides like total shit on the highway. If I put force downward on the car to make it bounce, the front comes back up and remains stiff.

The rear bounces once then goes back. Why would this happen?

Have you tried adjusting the dampening?

todd5854
12-28-2012, 09:45 PM
Here's a problem..

When I first installed my coilovers, I didnt realize that stupid shit convertible stuff was in the way... the dampening knob was constantly hitting something, bending the screw. A few months ago I noticed this, and used a die grinder to create an opening for the knobs.. I bent them, they don't turn properly.

Can I replace these? I can turn them with vice grips but I still don't know if I'm turning them too far, or etc.... really fucking pissed about this one

todd5854
12-28-2012, 09:46 PM
But I did turn them a few notches with vice grips, I turned them toward "HI" which I assume is a tighter setting. Just a few notches though

Driftwurks
12-28-2012, 10:07 PM
Here's a problem..

When I first installed my coilovers, I didnt realize that stupid shit convertible stuff was in the way... the dampening knob was constantly hitting something, bending the screw. A few months ago I noticed this, and used a die grinder to create an opening for the knobs.. I bent them, they don't turn properly.

Can I replace these? I can turn them with vice grips but I still don't know if I'm turning them too far, or etc.... really fucking pissed about this one

I'm not 100% sure because I don't have the same coilovers as you do. My best guess would be to contact the company and ask about replacement adjustment knobs which they should have. This link has some useful information. Megan Racing (http://www.meganracing.com/new/tech/faqs.asp?id=74&subject=CDK:%20%20Damper%20Force%20Adjustment%20Kn ob%20Information) Also, about not knowing whether you are turning them too far or not, don't they click everytime you go up or down one dampening setting? That's how my coilovers work.

todd5854
12-28-2012, 10:11 PM
I'm not 100% sure because I don't have the same coilovers as you do. My best guess would be to contact the company and ask about replacement adjustment knobs which they should have. This link has some useful information. Megan Racing (http://www.meganracing.com/new/tech/faqs.asp?id=74&subject=CDK:%20%20Damper%20Force%20Adjustment%20Kn ob%20Information) Also, about not knowing whether you are turning them too far or not, don't they click everytime you go up or down one dampening setting? That's how my coilovers work.

Mine click every notch. But since the screws are bent, then don't click at all now.

My fronts are set 12 clicks from the HI and ride nice and tight. Is there anything else I can try to get these things to ride smoothly? :/

codyace
12-28-2012, 10:37 PM
Back all adjustments off to zero, raise car up to a normal ride height. Drive car. Dampen front more than the rear. Big rear sway bar will make it slid more than needed.

With all entry level coilvoers, I always suggest going in full soft, and then adjusting as you go.

todd5854
12-28-2012, 10:47 PM
Full soft makes it more bouncy, correct? I have the car about 1.5 inches lowered as we speak. the front seems fine to me, nice and tight, but not too bad.. I feel as if I could soften it just by turning the knobs.

The rear... ugh. Okay, so I turn the knobs to "LOW" for the rears, and raise to stock ride height, and function and form factory-set pre-load, then go from there?

I was told that coilover springs should be able to be turned around by hand, but no vertical play. is this true?

Driftwurks
12-28-2012, 11:01 PM
Full soft makes it more bouncy, correct? I have the car about 1.5 inches lowered as we speak. the front seems fine to me, nice and tight, but not too bad.. I feel as if I could soften it just by turning the knobs.

The rear... ugh. Okay, so I turn the knobs to "LOW" for the rears, and raise to stock ride height, and function and form factory-set pre-load, then go from there?

I was told that coilover springs should be able to be turned around by hand, but no vertical play. is this true?

That would mean you have set the coilovers at zero pre-load. Depending on what your coilover manufacturer recommends, this may or may not be the correct pre-load level. Contact them or look on their website and find out what you are supposed to set the pre-load to. As for adjusting your ride height, you probably want an even level front to back. Raising your car should make the ride more comfortable as the springs will have more room to travel although 1.5 inches shouldn't be a big problem depending on the suspension specs. I have PBM Competition coilovers and I ride on full soft and I feel that it's tolerable for daily driving.

todd5854
12-28-2012, 11:11 PM
That would mean you have set the coilovers at zero pre-load. Depending on what your coilover manufacturer recommends, this may or may not be the correct pre-load level. Contact them or look on their website and find out what you are supposed to set the pre-load to. As for adjusting your ride height, you probably want an even level front to back. Raising your car should make the ride more comfortable as the springs will have more room to travel although 1.5 inches shouldn't be a big problem depending on the suspension specs. I have PBM Competition coilovers and I ride on full soft and I feel that it's tolerable for daily driving.

Okay, that makes sense. 5mm preload the website says.. They said take the length of the spring, in mm, and tighten it 5, and that's the preload.

So I should raise it more on that specified preload, and see if problem goes away? After I get 17's it will be higher up anyway.. stock wheels on 195/55 tires right now.. tiny.

Driftwurks
12-28-2012, 11:20 PM
Okay, that makes sense. 5mm preload the website says.. They said take the length of the spring, in mm, and tighten it 5, and that's the preload.

So I should raise it more on that specified preload, and see if problem goes away? After I get 17's it will be higher up anyway.. stock wheels on 195/55 tires right now.. tiny.
The first thing you should do is set the pre-load properly so the coilovers will perform how they were designed to perform. If that doesn't make the ride more tolerable, I would mess with the dampening and go from there.

todd5854
12-28-2012, 11:26 PM
I'll give this a try ^ and then report my findings tomorrow. Thank you everyone.

Driftwurks
12-28-2012, 11:32 PM
I'll give this a try ^ and then report my findings tomorrow. Thank you everyone.

Incorrect pre-load will definitely have an adverse effect on ride quality. I know this through first-hand experience. When I had my coilovers installed, the pre-load was not set so the spring was not sitting in place all the time. I adjusted the pre-load myself to the proper level and now the car rides much better and smoother.

codyace
12-29-2012, 09:31 PM
Full soft makes it more bouncy, correct? I have the car about 1.5 inches lowered as we speak. the front seems fine to me, nice and tight, but not too bad.. I feel as if I could soften it just by turning the knobs.

The rear... ugh. Okay, so I turn the knobs to "LOW" for the rears, and raise to stock ride height, and function and form factory-set pre-load, then go from there?

I was told that coilover springs should be able to be turned around by hand, but no vertical play. is this true?


The last statement is correct, you want to raise the collar up into the spring until there is no lateral (up and down) movement, but you can slightly spin them....and that's to be measured under full droop (car jacked up, wheel down).

You want to turn the knobs all the way soft front and rear. Having them soft could make it more or less bouncy, that's dependent on the damper you have. I like to set up most street 240's with the fronts a few clicks hard, and the rear full soft, or maybe a pair of clicks.

As above, you want spring preload to be zero to minimal...just enough to keep the spring seated.

Most people go out and make the mistake of 'full hard and full hard sway bars' and thinking it will work best, when the reality is far from that. I really think there is no GOOD reason to run an aftermarket sway bar over the SE bar ever (maybe the whiteline bar as it's the smallest). Sure putting a bar on can make a car feel stiff, but it won't make it handle better....the age old debate of 'feels good' vs 'performs good' has allowed many car guys to drive slow vs fast :D


fwiw: most entry level coilovers perform best with as few dampening clicks as possible, as the damper suck and the spring rates are bad. Keeping it soft allows it to 'sort of' work.

That would mean you have set the coilovers at zero pre-load. Depending on what your coilover manufacturer recommends, this may or may not be the correct pre-load level. Contact them or look on their website and find out what you are supposed to set the pre-load to. As for adjusting your ride height, you probably want an even level front to back. Raising your car should make the ride more comfortable as the springs will have more room to travel although 1.5 inches shouldn't be a big problem depending on the suspension specs. I have PBM Competition coilovers and I ride on full soft and I feel that it's tolerable for daily driving.

Preload should always be minimal on a double adjustable setup...5mm is negligible, it's basically telling you snug the spring, that's it.

Raising your car will make your ride more comfortable because it fixes roll centers, bumpsteer...not because the springs will travel more (whatever that means is beyond me). With ANY car the two biggest things that negatively effect ride are what I mention above, and 240sx's are especially effected by those two issues due to it being macphearson based in the front.




I know you're trying to help, but you need to really learn what is going on first before just copy/pasting what you've read. Check out the suspension angle thread, and other various threads to see how it all works.

Driftwurks
12-29-2012, 10:06 PM
Thanks for correcting me Cody. I actually didn't copy & paste any of the information that I posted. I was just under the impression that being slammed you have already messed with the pre-load to be able to lower your car even more than usual. Doesn't that mean the springs will feel stiffer and usually bouncier due to the added pre-load? What I meant to say was that aren't the springs going to have less room to compress if you are slammed? Thanks again for correcting me, you don't often see other members correcting each other rather flaming or making fun of the person who was incorrect.

Croustibat
12-30-2012, 06:38 AM
You are using coilovers. Changing ride height does not affect spring travel ...unless you are adjusting height by changing preload, which is very very very bad.

Springs dont make the car bounce, damper setting do. These entry level coilovers have radical changes in damping from 1 click to another one, so you need to change them 1 click by 1 click. Try it on full soft then on full hard, you will see what i mean ;)

also, make sure you dont preload the anti roll bars when adjusting height. Otherwise it will handle even shittier... you need to disconnect the droplinks before adjusting height, and then connect the droplinks so they dont apply a preload. Use shims if needed.

todd5854
12-30-2012, 07:35 AM
Sorry for not posting the updates, its been snowing in shitty PA lately, so I haven't felt like doing anything. Although I think I'll at least adjust the dampers before work in the rear.

The fronts I have dialed in 20 clicks from soft, or 12 clicks from highest setting. It's rigid but not bad at all. To be honest they feel almost as good as my friend's BC Coilovers.

-5mm is the preload for FF2 coils. The website mentions that all of their springs are a certain size, 150mm to 175mm for example... the preload should subtract 5mm off the coil. So I would assume that this is the best preload for them.

When I slammed my car when I first got these, I lowered them the proper way, not adjusting preload at all.

Croustibat
12-30-2012, 07:42 AM
To lower a car the proper way, you need new knucles and/or lower ball joints with longer shank, which i think you didnt buy (because they are expensive :D )

but at least you did the height change correctly. Did you get an alignment done since you changed the ride height ? rising the cars removes camber, toes the rear out and the front changes too. Which could explain why it goes all over the place.

Most of the time the car gets more controllable with closed hydraulics and very hard springs... the only reason for that is a very bad suspension. Locking it in place makes you run all the time with the static settings. Which again is not good, because the static settings are supposed to be made so the car handles when the suspension is working.

Anyway... if the car is still all over the place, close rear hydraulics a bit more.