Maven

iTrader: (1)

Ive been getting asked these questions a lot lately. A lot of discussions happen about these bars, how great they are, how they reduce body roll. how they make a car handle better, even how they make a car handle more consistantly. I am not talking about any of these claims. It seems quite a few of the threads have just gotten to the point where they are over many peoples heads. Talk of roll stiffness, roll centers, ride frequency, functions of diameter to the fourth power and on and on....if youy understand all that great, if not I am going to try to very simply explain what "sway" bars do, and how they do it.

Here is a picture I took/colored in so you can more easily visualize whats we are talking about. This is what the sway bar, mounts and links would look like from the drivers seat if you could see them. RED is the drivers side of car, blue is PASSENGER side of car. The boxes are the mounts that hold bar to the car itself, the lines are the links that connect bar to struts(the table)


First the basics, yes its a spring, but forget that....its just a rod, a rod fixed to the car body in the middle, with the ends fixed to the suspension on the ends.

Its connected to the body, so if the body moves the bar goes with it.

Its connected to the suspension, so if the suspension moves the bar goes with it.

Now you see the basics of how it works, since it moves when either the body or the suspension moves, and the suspension and the body move differently from each other(thats the whole point of suspension basically right?) that the bar is constantly trying to keep the relationship between the body and suspension the same....it has to....its connected to both.

Now where people get confused is how a bigger bar can be bad. If all its doing is keeping suspension and body in the same position relative to each it must be good right?
(for our examples imagine our bar is infinitely stiff, meaning it cant flex at all)
Imagine our car is turning left....the body is gonna wanna roll over to the outside of the turn, or to the right....so the right side of the bar(blue) is getting pushed down, and left(red) side is goin to be lifting up......follow?

Okay, now since our bar is linked to the suspension on the right(blue), the body cant just keep rolling to right and pushing the bar closer to the ground. the bar wont let the body change its distance to the ground as compared to the suspension, since the wheel is on the ground, the only thing it can do is push it harder into the ground And on the left(red) side the body is trying to lift up, its trying to get farther away from the ground, but its linked to the suspension, so the bar cant move any farther away from the ground either.....UNLESS......the suspension does!!!!! Thats right....the force of the body roll will actually use the bar to lift up the inside wheel!!!!!!

I hope thats easy to see.......

So how how does thickness matter? Well sway bars dont really have infinite stiffness like our example does....they have varying stiffness, if the bar is soft and its easier for the bar to twist than for the wheel to come off the ground, thats what will happen, the bar will twist, the body can then roll and the wheels stay on the ground....the stiffer the bar gets the harder it gets to twist, with every step in size the bar becomes harder to twist, the harder the bar is to twist the more weight is taken off of the inside wheel when the body rolls.

knoxbox

so is the ttr bar to stiff? at 25.4mm? if so what is a happier medium?

and the 29mm front eibach bar is it going to be too stiff? if so what is a happier medium?

or does all this depend on what i'm going to be using the car for?

thanks

p.s. very informative post woo hoo!

ZeeBee

very nice write up subscribed

Maven

iTrader: (1)

The TTR rear bar is imo too stiff for mostly stock or street driven only Cobalt. Nothing wrong with it, its just a lot of bar for day to day use, and can be a handful to drive for some people under some conditions. an approximately 7/8" solid bar(or equivalent) is a better balance for a mostly stock or only street driven Cobalt. In the end its all personal preference though.

I doubt anyone would argue that the Eibach isnt too stiff. As of right now the only other choices are the 22mm FE3 bar and the 24mm FE5 bar.

Yes, of course this is always key factor.

I am hoping that this new Eibach setup is going to be a little poke in the side for some of the other companies out their, and I wouldnt be horribly suprised if sometime in the future you hear announcements of potential new product.

knoxbox

i'm doing mostly suspension stuff right now as i plan on attempting autox for the first time next summer. this is why i went for the 25.4mm ttr rear bar, and i was considering the 29mm front sway from eibach as its the stiffest combo i could find thus far. i do daily drive this car and have had the ttr bar for over 2 months i'd say. and i love it. just wanted to make sure i wasn't going to be damaging anything by putting the eibach front one on or having the ttr rear bar.

thanks maven your post are always so informative.

well if someone makes a stiffer front before i go to buy then awesome tha'd be great.

as far as the subframe bar that ttr is getting there feet wet with... would that be a good addition for autox you can pm me if you would rather.

07cobaltguy

im glad you made this thread, im going to be doing autox in spring, and im working on my suspension set up right now, so would the TTR bar be benificial to me? since iwill be in a high stress situation for the suspension

Maven

iTrader: (1)

Youre kind of missing the message here, read what a super stiff front bar will do again....I think youll agree that 29mm(thats 2.13 times stiffer than FE5!!!)is too big. I was saying that I think its possible that someone may come out with a bar softer than Eibachs, but still slightly stiffer than FE5.



The subframe bar.........I am gonna say spend your money on something else.
Is TTR actually even making one? I hadnt seen any posts lately that said they were doing it for sure.

Absolutely, if it suits the surfaces youll be running and your driving style.

knoxbox

no they are just doing feelers as far as ttr.

i know what you said before but that was based on daily driver, i was talking about autox so you think its even to stiff for autox?

maybe i missed something i dunno haha.

Maven

iTrader: (1)

I think the Eibach front bar is too stiff for anything other than your modlist.


Okay, simple version: the Eibach front bar is gonna virtually assure that you burn off your inside front tire

rocketpunch1221

Let me answer your question with a question.

What do you think a stiffer front ARB will do to your car? and What kind of handling are you trying to achieve when you auto-x your car?

I don't think anyone can tell you if something is too stiff or too soft for your car if they don't know how your car is being set-up.

I don't mean to sound critical, but if your are new to the sport I think you should concentrate on the driving part rather than worry about your set-up.

Stiner

Why do I keep breaking my stock front sway bar?

TurboTechRacing

iTrader: (24)

27MM front solid bar or equivalent (about 60% over the stock FE5 front sway bar) would be better than the 29MM Eibach.

We are investigating this at the current time.

It was brought to our attention and suggested to produce:

1"OD x .109" hollow tube rear bar (slightly more rigid than a solid 22MM bar, yet slightly less rigid than a 25MM bar)

Also, with a hollow front bar equivalent to a 25 or 27MM solid.


Hollow would be much lighter, somewhere around 1/3-1/2 the weight of a solid, but would be slightly more in cost.

You broke it, meaning twisted it past yield?

Stiner

I've had two break on me. My dealer hasn't mentioned anything to me jus replaced them.

Maven

iTrader: (1)

Que??

So you broke two sway bars in some way that you were unaware of?

Stiner

It was snapped in half not right in the middle but you know. I suppose it was twisted past yield. How far is that on the stock one? Is that common? Maybe I'm just a goon I broke a couple roll pins my sway bar my flexpipe im on a roll ha

Maven

iTrader: (1)

Ive never had to replace a broken bar on a Balt, but I am sure it could happen.

Stiner

Alright cool sorry for the thread jack. What rear sway bar would you recommend for mainly street use with the odd fairly aggressive track run?

Maven

iTrader: (1)

On an SS? stock is an option If I had to pick a bar for that type of driving I'd say the softer bar. IE: Progress 22mm or TTRs possibly forthcoming 1" hollow bar

qwikredline

something is seriously wrong stiner drop by and i will check it you wish and let you know

come on by and we can fit a time attack chrome moly tubular bar. the rest of this stuff is what it shouldnt be...

the 29 mm bar in auto-x tight turns will plow all the way to louisana...

and let me ask you a question. What set up could you conceivably develop that would be superior to GM developed road racing set-ups? Just asking... oh and they dont use a 29 mm front bar or a 25 mm solid rear...

aveoturbo

(:

Stiner

Alright I took a look at my work order for the first time I went into the shop it says my swaybar link was broken. The next time though it was broke in half so I'm thinking possible mechanic error? The first time I went in it was a fairly minor rattle I just mentioned it when i brought it in for a new flex pipe. The second time was loud and u could see that it was in two pieces lol.


Qwik I'll bring it in anyways Probably won't be till after xmas though I'm finishing exams then i'll be workin 6 days a week until xmas. Then I'll actually have some dough to by something haha

Maven

iTrader: (1)

I though that was for me??

Yup, agreed. Obviously if cost wasnt an option a suspension setup stolen straight from the TA or a Grand Am car would be ideal........but in the absence of about $8600USD We probably agree that a properly sized add-on rear bar, FE5 suspension and your choice of springs is about as good as it gets on the street(unless someone happens to be a fan of the "economy" coilovers out there in the $1000-1500 range)

Don Juan

k so question a have a progress tech rear bar but i was thinking about selling it and getting the ttr. I know it will have less body roll and more oversteer. But will it be to much that i will be dissatisfied with the results, being to stiff? It's on a HHR lowered about 2" with goldlines. Or do you think i would be alright being that its on a hhr with more roll/weight?

Maven

iTrader: (1)

Thats up to you really. Do you like the way it handles with the Progress bar? Or do you think youd like less traction in the back? The TTR bar is over 65% stiffer than the Progress.





As a side note I just want say that I noticed TTR has finally put up some actual information about how their bar compares to the Progress on their website. They took a lot of **** for a long time(deservedly so) from many people including ME for not providing any product details.

Halfcent

Did I inspire you or something?