Wow...someone else without any sort of information to backup claims. I'll agree with D Cell's aero comments, but not with his swaybar arguement.

The swaybar adds roll stiffness, and thats why it limits dynamic camber, because it doesn't allow as much camber since the wheel won't compress as much. Is this what you're talking about?

It's really quite simple, and a 2nd year ME major can do the calculations for you if you give them the required information.

Maybe you could try and be a little less cryptic with your posts.

 

Doc, every post in this thread has been referring to autocross setup. Who ever mentioned road racing?

Camber can be "controlled" by means other than swaybars. Additional static camber or other geometric changes, spring rate adjustment, etc.

 

Dr Cortez- if your talking about controlling camber in you will gain too much on compression, most 4gcivic folks dont have any camber adjustment. so they usually adjust it via pyromoter and ride height. (untill i get us some adjustable uca's made )

i dont think the lca is going to move inward or outward in relation to the veichle enough to drasticly change camber angles. although i have heard this theory on using front bars, i realy dont understand why. its nothing that cant be corrected with spring rate (which i have plenty of). and with my set-up for autocross (minimal droop travel & open diff) the last thing i want is something to pick up the wheel.

lay your theory out so everyone can try to grasp it (like me)

-spenc

 

Ok, let's see if I get this right... we enter a corner, and the tire starts generating a significant cornering force, but because we don't have a sturdy front sway bar, that LCA wobbles around and we loose camber/toe/etc....

ok... hmmm...

Let's try thinking some more rather than reading another thread.

You keep harping on the concept of camber control. I assume you're not just talking about loosing camber due to roll, but actual chassis flex and loss of camber due to that. So then you seem to keep saying that removing the front bar will significantly affect the stiffness of the LCA mounts, and thus, more flex and loss of camber. However, if you look at a swaybar, you'll see that they are in these nifty bushings that they can slide in and out of. In the exact direction you are so concerned with stiffness (for camber controll), there is virtually no stiffness provided by the sway bar in comparision to any chassis, no matter how flexible.

Now if you wanted to stiffen that area, we could add and aptly named LCA brace. Though I even question how much an untriangulated brace will help with camber controll given that the outside LCA is in compression while the inside is in tension, thus just making the whole assembly move. However, whatever chassis stiffness it provides will far exceed the stiffness from running a front sway bar, and at a lower weight.

The only way to really up the chassis stiffness is to triangulate all the suspension to other points in the chassis (not the other LCA), but that's not legal in most autocross classes, and a sway-bar certainly doesn't do that.

I have no doubt that 4th gen civics don't have the sturdiest suspension mounts in the world, but I just don't understand how the swaybar can have a significant effect on the stiffness of the front suspension geometry.

Now maybe I got you all wrong and you are talking about loosing camber due to roll... if that's the case... you can get around that by running stiff springs or a bigger rear bar.

Please, explain what you're saying with more than three lines of almost unrelated statements.



Modified by Jreyenga at 2:26 AM 3/31/2004

 

Replaced all my bushings last week and noticed the front swaybar bushings were all worn...I heard that some peeps here had better control or less understeer when the front swaybars on FWD cars were taken out...Why did Honda install one in the first place? Should I replace my front swaybar with an aftermarket one like ST? I replaced my rear sway awhile back and it made a hellofa difference...should I expect the same results in replacing the front?

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by jzr &raquo;</TD></TR><TR><TD CLASS="quote">Doc, every post in this thread has been referring to autocross setup. Who ever mentioned road racing?
</TD></TR></TABLE>

Spenc does track events , I started this whole debate in responding to his post.

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by jzr &raquo;</TD></TR><TR><TD CLASS="quote">Camber can be "controlled" by means other than swaybars. Additional static camber or other geometric changes, spring rate adjustment, etc.</TD></TR></TABLE>

how so , you're still missing the point of why that front bar is so beneficial.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Doctor CorteZ &raquo;</TD></TR><TR><TD CLASS="quote">how so , you're still missing the point of why that front bar is so beneficial.</TD></TR></TABLE>

Can you explain it so the dummies like me can figure out what you're talking about?

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Doctor CorteZ &raquo;</TD></TR><TR><TD CLASS="quote"> you're still missing the point of why that front bar is so beneficial.


</TD></TR></TABLE>

I think everybody who has setup a fast crx/4th gen civic is also missing your point. Smaller/No front sway bar is faster. Both on track and auto-x

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by ryan12321 &raquo;</TD></TR><TR><TD CLASS="quote">

Smaller/No front sway bar is faster. Both on track and auto-x</TD></TR></TABLE>

yeah , sure it is.

I'm done with this , you wanna figure it out , read a book or something.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Doctor CorteZ &raquo;</TD></TR><TR><TD CLASS="quote">I'm done with this , you wanna figure it out , read a book or something.</TD></TR></TABLE>

Well, books dont win races.

I cant read anyways, i just look at the pictures. I'm finding that books about actually driving are much more beneficial than books about chassis setup for me.

RJ - who will ride the short bus home today

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by .RJ &raquo;</TD></TR><TR><TD CLASS="quote">

Well, books dont win races.

</TD></TR></TABLE>

some do.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by .RJ &raquo;</TD></TR><TR><TD CLASS="quote">RJ - who will ride the short bus home today</TD></TR></TABLE>

like that's not the bus you ride home everyday? please... I don't get it either, I guess I'll have to start reading dammit.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by ryan12321 &raquo;</TD></TR><TR><TD CLASS="quote">Smaller/No front sway bar is faster. Both on track and auto-x</TD></TR></TABLE>

a lot of fast people ARE running without a front swaybar. an even larger number of slow people are also doing the same thing. the slow outnumber the fast by and large, so clearly something else must be involved or the magic setup would be fast for everyone. whats that you say? what about the driver??

no offense intended towards anyone, but if you don't know/realize/understand the reasons to use a a front swaybar, then you also don't know/realize/understand why you might not want to run a front bar.

for some reason everyone thinks a front swaybar will cause understeer 100% of the time. in a perfectly balanced rear drive car, ok. in a front heavy, fwd car there are a large number of other factors that are contributing to understeer. you can band-aid by removing the front bar, then band-aid the increased roll by adding more spring rate, then band-aid the spring rate with different shock valving, etc. until you fix the real problem all you'll be doing is throwing band-aids at a severed artery.

which is faster? i'm not sure. it would make sense that the more balanced combination would be good at a wider variety of surfaces, grip levels, and corner types. however, the wild card, the driver, can alter any of that to a large degree.

nate

 

Nate,

But what is this "deflection" that Cortez is talking about? It seems this is the biggest issue here. Mr. Cryptic Writing won't explain anything, and then gives up...

Maybe you can explain better.....or at all

 

I guess we're back to square one...What is it anyway? All I know is that John Thomas who drives a 5th gen Civic, 10 or 11 straight nat'l championship has a front swaybay

 

&lt;--------

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by PseudoRealityX &raquo;</TD></TR><TR><TD CLASS="quote">Nate,

But what is this "deflection" that Cortez is talking about? It seems this is the biggest issue here. Mr. Cryptic Writing won't explain anything, and then gives up...

Maybe you can explain better.....or at all</TD></TR></TABLE>

I am agreeing with Nate's position on this. "DRIVING" and how you approach a corner has alot to do with the car's behavior in corners. With that given I believe you set the car up with the spring rates and use the sway bars to fine tune the behavior.

It has been my experience that if have properly funcitioning sway bars that do not bind, adds a better transitional feel and predictability to the car rather than tuning with just springs alone.

Perhaps without the sway bar the "deflection" Cortez is talking about comes from the suspension corners acting in a pure independency from the opposing side of the car. I dunno, I always subscribed to the fact that deflection was minimized through hard(er) composition bushings and passive camber control such as shock tower and subframe braces.

Nate, am I getting close on this?

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by EF_LSVtec &raquo;</TD></TR><TR><TD CLASS="quote">I guess we're back to square one...What is it anyway? All I know is that John Thomas who drives a 5th gen Civic, 10 or 11 straight nat'l championship has a front swaybay </TD></TR></TABLE>

It's a 3rd gen Civic. Torsion bar front suspension.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by DerangedEG &raquo;</TD></TR><TR><TD CLASS="quote">

I am agreeing with Nate's position on this. "DRIVING" and how you approach a corner has alot to do with the car's behavior in corners. With that given I believe you set the car up with the spring rates and use the sway bars to fine tune the behavior. </TD></TR></TABLE>

My arguement is simply that Cortez's description of what is happening is confusing and incorrect. There are very likely things that I'm not thinking of, but "deflection that causes negative camber" is simply a roll stiffness issue if you're thinking the control arm is rigid, and if it's not, then a swaybar is NOT going to help you.

 

Edit: after realizing that "deflection" simply means the LCAs normal movement, only the last part is relevant. I figured "flapping in the breeze" refers to unchecked bushing deformation.

For some reason, I'm kinda interested, so I'll go through to see what deflection the sway prevents. Looking at the various axes of motion and they are constrained (or if they are constained). I'm assuming that the LCA is rigid, since if it strains, the forces are large so that the swaybar isn't doing **** to stop it. So I assume we're talking bushing deflection.

-In the front-of-car/rear-of-car axis which the LCA is in planar motion about (linear motion), the sway bar should offer some resistance, thanks to the subframe mounts, but that depends on the sway bushings. However deflection here won't cause a camber change. A radius rod does a better job preventing this motion.

-Horizontal delfection of the LCA mount will cause a camber change (by horizontal I mean toward the wheel). The swaybar can only resist horizontal forces through the endlinks, which I don't see doing much, since they consist of vertically aligned poly bushings or a rod end. Horizontal forces are reacted into the other LCA, so I don't see a sway helping here.

-Vertical deflection of the LCA inboard bushing should cause a small change in camber, if the LCA isn't vertical. The sway will simply rotate unless there is vertical movement of only one LCA.

-Rotation about horizontal axis of LCA =&gt; LCA twists. Camber won't change, but the sway won't help you if it did.

-Rotation about vertical axis of LCA. I suppose there would be a camber change since the effective length of the LCA would change through the horizontal arc. The inboard sway bushings will provide a resistive force, dependent upon the bending stiffness of the bar and the stiffness of its bushings.

-Rotation about the front-rear axis. This is the only axis the LCA is supposed to move in, and the inboard LCA bushings better not offer much resistance. Most camber change (pretty much all of it) occurs here. The sway will (that's how it functions) resists this rotation. Of course the spring will too (and the shock to some extent). I'm pretty sure the swaybar won't do anything significant EXCEPT in this axis.

Why don't we just use springs? The only differences between a huge bar and huge springrates are:

1. The sway conncetion between LCAs causes additional WT at the front (compared to no bar) since the bar unloads the inside to resist the LCA rotation. Total WT doesn't change, just the relative front/rear WT.

2. The magnitude of the swaybar force changes as it twists. Since it's bending through an arc, the effective moment placed on the arm will change. Linear springs are linear springs so the force doesn't change, and I don't want to talk about shocks.

3. Swaybars don't work too well w/o springs.

4. Anyone?

The only "camber control" I see comes mostly from #2. The rate of wheel deflection is different through the bump stroke with a sway =&gt; more resistive force from the sway as the effective moment on the arm decreases, which is a good thing. It gets stiffer as bump increases. I guess there's camber control from inducing additional WT at the front. This causes positive camber change from roll and negative camber form the wheel moving further into bump.

So...um...yeah


Modified by GSpeedR at 12:50 PM 4/1/2004

 

i didn't think that doctor cortez was that cryptic at all, but then i knew what he was getting at.

the deflection he was referring to was purely the relation between the static camber setting and the amount of camber gain in bump, versus the camber loss in roll and the amount of camber the tire needs to be happy. the a-arm suspension we are talking about does have some nice camber gain properties, but it isn't perfect. no system can be without compromising many other parameters. there is still more camber loss in roll then gain in bump and it isn't always desirable to keep adding static negative camber to overcome this. therefore you must add some level of roll stiffness so that at your terminal roll angle your outside front tire is happy.

can enough roll stiffness be attained without a front swaybar? probably, especially when we aren't constraining ourselves with stock camber adjustment, or lack thereof. hell, with stock springs and -5* of camber we'd probably come out pretty close, but we come back to the question of "why remove the front swaybar?"

if we are to do anything, we best have a good reason. we add wider wheels and stickier tires because they increase grip. we add better shocks because they control the chassis better. we reduce weight and increase horsepower so the car will accelerate better. each of these has a strong benefit with acceptable negative side effects. so why are we removing the front swaybar? other then the reduction in weight, all other "benefits" can be obtained through other means. ones that have fewer undesirable/unacceptable negative side effects.

nate - hoping he didn't overstep his bounds

 

Okay, I read this entire thread hoping to gain some insight on suspension theories and what works in Auto-x.... and by the end I had this look on my face:


Then I thought I'd try to help this discussion out by posting pics of my filthy under carriage so people (I) can get a visual of what's being discussed.





My first thought when Doctor Cortez mentioned "deflection" was that he was assuming that the Sway bar was performing the task of the radius rods and that the slightest bump would bend the LCA to oblivion. As I read on I realized that was not the case, but still felt the need to reply to that logic by pointing out that the '91 Civic STD HB does not come with any sway bars and the front end seems to hold up fine.

I realize that I'm not adding any value whatsoever to this conversation, I'm just trying to work this through by typing it out.

I'll shut up now.

-Louie, who's heading over to the short bus to join .RJ now....

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by thumpu77 &raquo;</TD></TR><TR><TD CLASS="quote">but still felt the need to reply to that logic by pointing out that the '91 Civic STD HB does not come with any sway bars and the front end seems to hold up fine.

</TD></TR></TABLE>

fine , I was never really content with fine when better was always out there.

most civics dont come with rear swaybars either , is that fine ?

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Doctor CorteZ &raquo;</TD></TR><TR><TD CLASS="quote">

fine , I was never really content with fine when better was always out there.

most civics dont come with rear swaybars either , is that fine ?</TD></TR></TABLE>

Depending on spring rates, yes

 

I agree with Nate's interpretation of the Doc's cryptic dialog.

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote &raquo;</TD></TR><TR><TD CLASS="quote">other then the reduction in weight, all other "benefits" can be obtained through other means. ones that have fewer undesirable/unacceptable negative side effects.</TD></TR></TABLE>
I tend to think as no swaybar as simply another notch on a sliding scale of front swaybar stiffness.
Stock Si bar=2
HF front bar=1
No front bar=0
Nothing magical happens going between any of these steps; the differences are gradual.

We'll probably test out the HF bar this year, along with a few other things.