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View Full Version : eliminating chassis flex creaks.



kayot1k
10-09-2006, 04:29 PM
hey fellas, just noticed after having no music in my car for over a week or so now, i have some awfull chassis creaks in the rear of me car.
car is EK hatch. i have a pretty stiff suspension setup on my car atm so it might explain some of the flexing as i run my car hard .

right now im not running any rear strut brace or c-pillar etc..
just stock front strut brace.
now, i was thinking a rear strut brace would ease some of this noise/flexin and probably make my in cabin noise abit quieter. i was told once you go hardcore with your suspension you really cant stop the creakin as a result of stiff suspensions.


anyone have this sorta problem running a ek hatch ?
any suggestions/solutions with similar problems would be great thanks.

regards
steve

ekhybrid
10-09-2006, 05:58 PM
i put in a rear strut brace in and it stopped most noises, until i put in my sway bar lol. the noises only occur wen i go on driveways tho.
is this the same with u or wen u drive around as well?

VTi_b0i
10-09-2006, 06:33 PM
my rear sway bar makes HEAPS of noise but a rear strut should hopefully stop it. maybe something needs lubing?

mrwillz
10-09-2006, 06:40 PM
. the noises only occur wen i go on driveways tho.
is this the same with u or wen u drive around as well?

happensn for me

kayot1k
11-09-2006, 12:45 AM
i would agree the loudest or the worst creaks are entering and exiting driveway type scenarios !!!!

also, after upgrading the rear sway bar i did notice like a few of you guys said, it did go louder and more consistent more after than before ?

it also creaks when driving through uneven roads such as parramatta rd and humehwy , two of the worst main roads i have come across.
i would hafta say mostly uneven roads.

Vti-boi, maybe you should lube your sway bushes? i was reading a thread not long ago about bushes making noises ...


regards

Limbo
11-09-2006, 10:43 AM
yeah due to lack of flexing your gonna get those noises.
It only happens on driveways for me otherwise it doen't make a noise.

kayot1k
11-09-2006, 03:09 PM
limbo what kind of rear re-enforcement bars do you ahve for the rear?
if you dont mind sharing.

regards

sifoo
11-09-2006, 03:10 PM
yeh same problem here - my rear sounds like it has canaries chirping at each other

It sounds like its from inside I dunno if its my rear swaybar or coilovers that has made that noise?

kayot1k
11-09-2006, 03:14 PM
im not 100% sure but i have a feeling some of the sounds are contributed by the rear trims that cover the tailight.

how does a squeaky swaybar sound like ?

VTi_b0i
11-09-2006, 03:15 PM
Vti-boi, maybe you should lube your sway bushes? i was reading a thread not long ago about bushes making noises ...
regards
yeahh i will get round to it one day steve haha

JasonGilholme
11-09-2006, 03:42 PM
I think the squeeks are from dry bushes where as the creeks are from sway bars and strut braces etc.

Greasing the bushes should remove the squeeks but as for the creeks... dunno.

Limbo
11-09-2006, 04:58 PM
chirping from my car are from the the rear seat which i haven't gotten around to fixing. I think just abit of bog should help fix it.

My rear i have a lower tiebar and a whiteline 18-24mm adjustable (custom order)

set at 24mm atm

PaZzMaN-R
11-09-2006, 06:46 PM
is it not the chassis twisting?
if it is the chassis twisting then souldnt strut bars contribute to fixing the problem?

lubing up the dry bushings sounds like a good idea.
give it a go steve and let us know how it goes

kayot1k
11-09-2006, 07:34 PM
yes sir

[ricer]
11-09-2006, 07:38 PM
im not 100% sure but i have a feeling some of the sounds are contributed by the rear trims that cover the tailight.

how does a squeaky swaybar sound like ?

omfg mines exactly in the same place
and io tried pulling my tail light out and all and still no fix
pm me if u find the problem please man

revNhevN
11-09-2006, 09:53 PM
my parcel try jumps around. different parts of the car vibrate at different rpms. i find turning up the radio hide the noises.:thumbsup:

mr173
11-09-2006, 10:41 PM
Try to have a softer trye presure, it should works.
I have a EK civic too, when ever I have harden my tryes to 38 -42psi it have a lot of noise from the back, when I reduce the pressure to 32-36, most of it gone.
it work in my car, please let us know your result.

kayot1k
12-09-2006, 12:11 AM
heehee.
im only running 32psi in the rears and 33psi in the fronts yo.
ricer, do u have a rear strut brace/c-pillar ?

i do notice sometimes, the metal clips on the trims make some squeaky noises from time to time.
maybe using some wd40 should fix that matter.

mr173
12-09-2006, 01:10 AM
I have a rear brace but still stock shock's with sport spring.
may be wd40 will work for the clips, I don't know.
but I been eliminlate noise from the suspension with WD40 too..sprays on the stroke inside the protective boot and the top mounting seal.
also have been found noise from losen bolt of seat too, just tighten up.
but I still can't solve the tailgate noise

slidetaker
12-09-2006, 01:58 PM
For chassis flex, get a rollcage...

[ricer]
12-09-2006, 09:38 PM
i got a c pillar
the rear strut is hard to put on ek unless u take the trims off or cut them

Muzz
15-11-2006, 10:43 PM
For chassis flex, get a rollcage...
roll cages in street cars usualy increase the chances of serious injury in road accidents are are highly not recomended by people who investigate colisions.

newbie
16-11-2006, 06:50 AM
you dont have to take the trims off .. just cut thru the plastic with a dremel/rotary tool

you notice it on driveways .. cuz your swaybar is trying to straighten your car on uneven ground... happens to me abit, but when i had my cpillar brace on, all my creaks went away. now its off.. they are back.. hahaha but not as bad though.

dupac->
16-11-2006, 09:05 AM
i got sways n struts, sways didnt make too much noise when i had them on by themselves, they knocked here n there with occasional squeek but tightening them fixed it. but now since i got the rear strut brace in makes heaps of noise over little humps, drive ways speed humps, well anything that i need to snake it up.
i might need to tighten the strut?
i dont think u could eliminate all the sounds..

slidetaker
17-11-2006, 10:19 AM
roll cages in street cars usualy increase the chances of serious injury in road accidents are are highly not recomended by people who investigate colisions.
Question is on the balance of how bad and your attitude towards chassis flexing VS how often you will cause an accident which require the attendance of crash site investigator...

Muzz
17-11-2006, 05:56 PM
the crash site investigator has nothing to do with what im talking about. Im saying its been proven time and time again that there is a MUCH greater chance of serious injury, in not so serious accidents. Eg, guy died in a very minor accident from cracking his scull on the windscreen bar. without a helmet and harnesses, roll cages are dangerous, even with good padding.

When i say people who investigate colisions, im not talking about the people who work out what happen in an accident, im talking about the people who design safty systems (harnesses seats cages etc. etc.) for race cars and road cars alike as there day job. All professionals in this industry have the same opionion - if its a road car and not used as a track car at all, having a roll cage is a very very bad idea.

if youd like i can post up a seminar from justracing.com regarding this exact issue, from a racing safty designer.

chef_32
18-11-2006, 11:26 AM
Do It!!!

Muzz
18-11-2006, 06:09 PM
http://www.justracing.com/seminar_archives/viewtopic.php?t=5

the saftey devices in your car are designed as a system, you cant just pic and choose what you want to add, you need to upgrade as a hole system.

eg. You remove the air bag steering wheel - that requires you to use harnesses to keep you from smacking the wheel with your head.
using harnesses - that requires you to add some sort of rollover protection eg a rollbar or cage. With ur stock 3pt seat belt, in the event of the roof crushing down, they allow ur body to be pushed out of the way, where harnesses will hold you upright, perfect if ud like spinal compression or a snapped neck. Very dangerous in a rollover without rollover protection.

Having a cage, padding or no padding, requires a helmet!
Using stock seats with a cage or rollbar? u should get a seat back brace to keep safe in a rear ender accident, most oem seats are designed to flex, some to break at the hinge, better yet, get a racing seat. Also harnesses cannot be saftly used with oem seats, unless they have the holes specifically for harnesses. Finally using a cage with oem 3pt seatbelts is highly dangerous.

Ignore any of these points and ull end up less safe than if you left the whole system stock.


For chassis flex, get a rollcage...

Saying "get a rollcage" when the OP asked what he can do to decrease chassis flex creeks is some very bad advice and also very ignorant. Too many people get cages for the COMPLETLY wrong reason:thumbdwn:

Muzz
18-11-2006, 07:43 PM
oh crap, that link speeks nothing of the roll cage in street car delima- still a good read though!

slidetaker
20-11-2006, 08:09 AM
Certainly a good and insightful read indeed. But from argument seek, a newie view, there is really about 2 inches of different between a person’s skull cracking on the roll bar or cracking on the chassis frame??? And when you are talking about skull cracking, which is caused by a great force, that couple of inches would not make a difference in the sense of the reduction of force with respect to space???

In situation of rollover or roof crashing down, I still cannot see why could a roll cage harmful instead of helpful against the impact with transferring the forces more evenly across the chassis given that it is installed in a professional manner?:confused:

Definitely agree on the point of having the complete race spec with bars, racing harness and seat and helmet. Surely it is the safest opinion. But in reality, there are still lowered car out there without an upgrade of shocks shows that everyone will mod their cars for different purposes. They might lower their cars for aesthetic reasons, not performance, just as a roll cage for chassis flex, not to comply real racing safety standards.

Please understand I am not trying to start a quarrel, but merely trying to get more information and learn more.;)

bennjamin
20-11-2006, 08:28 AM
(on a road car) also in an accident situation ~ the forces usually ABSORBED into the cars bodywork and chassis would actually expel the car further away IE "bounce" off the impact area. This would lead to massive damage to occupants inside and also possibly throwing said vehicle into more danger ( ie off a cliff , into other cars etc)

Muzz
20-11-2006, 04:06 PM
Certainly a good and insightful read indeed. But from argument seek, a newie view, there is really about 2 inches of different between a person’s skull cracking on the roll bar or cracking on the chassis frame??? And when you are talking about skull cracking, which is caused by a great force, that couple of inches would not make a difference in the sense of the reduction of force with respect to space???


I totaly understand where your coming from here. I am definatly no expert, just somone who is very interested in racing safety and trying to learn lots about it. So i cant give u a proper answer, only my opionion, which may very well be wrong.

Say u have a hard accident, and your head meets the halo bar running across the windscreen. All of the impact energy will be experianced by your head, you wont make a dint in the bar at all.

So your head may be moving at 30kph and come to complete stop in 0.5mm, to do this, the amount of deceleration would be extremly high.

using physics equation (Vf^2=Vi^2+2A(Xf-Xi)) You'd find that the deceleration your head would experiance in the above situation would be 69,723m/s or 7715g’s of force! No head could survive that!

Nearly everything around the cockpit of a car is designed to flex a little Eg. steering wheel, dash, door trims rooflining etc. incase of an impact.
(The windows are an exception to this, however if you hit the windscreen with the same force as in the above example, it wouldn’t decelerate your head that quickly, it would simply shatter (absorbing a little energy), and your head continue go through it. Your head would experience lots of damage and cuts, but it wouldn’t experience the MASSIVE g forces from instant deceleration (id say you’d still end up dead)).

So lets say your head hits something like the trim which allows your head to decelerate from 30kph to 0kph over 5mm (id say most trim pieces deform well over 5mm when hit hard enough), the deceleration would be 6970m/s or 711g’s. So if your head hits at 30kph, on the cage it would experience 7715g’s of force, where it may experience 711g’s of force or less if hitting the trim at the same speed. That’s a difference of over 10x the force your head is subjected to.

It’s hard to imagine, but picture yourself relative to the car during an impact. The interiors all perfectly still around you, and in the moment of impact your body’s thrown forward inside it.
In an accident harnesses/belts are designed to stretch an inch or so, and keep your body from experiencing sudden deceleration inside the cockpit (the cockpit is also decelerating as the nose is crushing up). Id guess that when your head is up near the top of the windscreen area the belts are in high tension and well into doing there job of pulling you up inside the interior. They do this very quickly, over maybe an inch or two? So one minute you could be moving forward at 50kph relative to the interior around you, and two inches later be moving 0kph relative to the interior. (that’s not to say your not moving, the nose of the car would still be crumpling & absorbing energy, so you, and the interior as a whole would be decelerating as one). So as you can see, the speed at which you decelerate inside the cockpit (as the cockpit decelerates aswell) means only a few inches can be the difference between hitting with full force, and just a little bump.

Muzz
20-11-2006, 04:11 PM
In situation of rollover or roof crashing down, I still cannot see why could a roll cage harmful instead of helpful against the impact with transferring the forces more evenly across the chassis given that it is installed in a professional manner?:confused:



I totally agree with you there:thumbsup: ur exactly right, if you dont dammage yourself on the cage, having it there in a rollover would be a huge benifit!

I think you just misinterpreded me saying that to be in a rollover, with harnesses but no cage or rollbar, is a very dangerous situation, due to the harnesses holding you in an upright position as the roof crushes down (stock 3pt belts are designed to allow you to be pushed out of the way by the roof)

Muzz
20-11-2006, 04:34 PM
They might lower their cars for aesthetic reasons, not performance, just as a roll cage for chassis flex, not to comply real racing safety standards.



Your exactly right there too, i just hate to seeing people make there street cars dangerous for asthetic reasons, or cus the driver want less flex for a car that he has no plans to take out on track.

If it is used on the track, then yeah i can see why one might want one put in for the other benifits, apart from safety:thumbsup:




Please understand I am not trying to start a quarrel, but merely trying to get more information and learn more.;)

yeah its cool mate, and iv been feeling like a bit of a ass after saying -

Saying "get a rollcage" when the OP asked what he can do to decrease chassis flex creeks is some very bad advice and also very ignorant. Too many people get cages for the COMPLETLY wrong reason:thumbdwn:

it was a bit harsh there, im not usually like that. i was having an absolute shit of a day. I parked at the shops next to a commodore with three dodgy lookin teenagers inside, when i came out i see my drivers side mirror is ripped of, and those dickheads gone:thumbdwn:

Muzz
20-11-2006, 04:41 PM
(on a road car) also in an accident situation ~ the forces usually ABSORBED into the cars bodywork and chassis would actually expel the car further away IE "bounce" off the impact area. This would lead to massive damage to occupants inside and also possibly throwing said vehicle into more danger ( ie off a cliff , into other cars etc)

:thumbsup: yeah the stiffer the car is, the greater the g forces experianced by the people inside it.