Suspension Springs, Shocks, Brakes

Hows the sway bar work? / How can one be too big?

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Old Dec 11, 2008 | 02:21 PM
  #26  
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Originally Posted by Maven
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.
Actually that information about the bar has been on there, and has not changed since March 2008.... Maybe you never noticed it. Only thing that has changed on the product page has been the price, and the "year update (2009)"
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Old Dec 11, 2008 | 03:22 PM
  #27  
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Originally Posted by Maven
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)
i have more than one maven com'on

Originally Posted by 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
Phew thats a relief Drop link broke thats understandable! TO break the actual roll bar would take some pretty devious forces at work...maybe a dewalt chop saw....
hey get your education and feel free to drop by you dont have to spend money to say hello and by the way we are not 3000 miles from where you live more

Originally Posted by 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?
Yeah Maven probably forgot to say this but with the height of your HHR at the rear all that mass up high your need for roll stiffness at the rear twb is LESS. So DONT go bigger at the rear buddy...tune your balance with tire pressures its that sensitive. Most folks around here tuning suspension take a bazooka to a knife fight. Small incremental changes are needed most times...

Last edited by qwikredline; Dec 11, 2008 at 03:22 PM. Reason: Automerged Doublepost
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Old Dec 11, 2008 | 04:23 PM
  #28  
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Originally Posted by qwikredline
i have more than one maven com'on
I know, I was just jealous



Most folks around here tuning suspension take a bazooka to a knife fight. Small incremental changes are needed most times...
Yes there seems to be quite a bit of the "stiff is good, so stiffer is better" going on around here. I know our options are relatively limited at this time for moderately priced upgrades guys, but please do your research before you bolt anything to your car. Just because the Koni cars run a bar 350% stiffer than stock doesnt mean you need to

I am gonna see if I can draw up any further helpful stuff on my kinematics software tonight, try and make it even easier to see how a sway bars true purpose also lies heavily in "reducing" traction.

Last edited by Maven; Dec 11, 2008 at 04:23 PM. Reason: Automerged Doublepost
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Old Dec 11, 2008 | 10:45 PM
  #29  
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Originally Posted by Maven
I know, I was just jealous





Yes there seems to be quite a bit of the "stiff is good, so stiffer is better" going on around here. I know our options are relatively limited at this time for moderately priced upgrades guys, but please do your research before you bolt anything to your car. Just because the Koni cars run a bar 350% stiffer than stock doesnt mean you need to

I am gonna see if I can draw up any further helpful stuff on my kinematics software tonight, try and make it even easier to see how a sway bars true purpose also lies heavily in "reducing" traction.
rule number 100: the more you f**k with it, the softer it gets....
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Old Dec 11, 2008 | 10:49 PM
  #30  
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I hear the SS front bars are pretty good they way they are... Is this true?

I have the TTR bar on my car and personally I think the car hold great, and with the drop, definitely an improvement from stock (no surprise there) so that earlier post is right, its mostly in the butt dyno and what it likes. lol

P.s. thanks for bringing this up. I knew the idea, but reading all the posts is helping me understand the physics more.
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Old Dec 11, 2008 | 10:55 PM
  #31  
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how can 29mm be to stiff? it should handle pretty damn good with it. damn near perfect balance. my old daytona had a 32mm fornt bar... and it was nicely balaced. so I cant see a 29mm on these cars being to much... I will test when I order one.
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Old Dec 11, 2008 | 11:00 PM
  #32  
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Originally Posted by cruisn
how can 29mm be to stiff? it should handle pretty damn good with it. damn near perfect balance. my old daytona had a 32mm fornt bar... and it was nicely balaced. so I cant see a 29mm on these cars being to much... I will test when I order one.
well heck based on your old daytona then the 38 mm front bar on the Z06 i just built should be fine lets scrap the pansy 29mm bar. comon this is a totally useless thread now imho
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Old Dec 11, 2008 | 11:10 PM
  #33  
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Well I will put my 2 cents in:

I started going to the track and I noticed I would go to turn hard but I would understeer. I wanted to fix this. I had a 06 Civic Si with a stock 19mm rear sway bar. I bought a 22mm rear sway bar along with a front sway bar. I noticed right away with the rear only installed, when I went into a corner, my rear end got whiped around feeling like I was going to oversteer around the corner but never did, it just through me into it.

I then put the front sway bar on and then I notice I was understeer alot once again and that was because the front was so stiff. I took the front sway bar off and test drive it without and it was even better and would into the corners even better.

I ended up keeping the new rear sway bar, put the stock one back on the front and thats how it was until the day I sold it.

Just my experience.

I think on my SS, I am going to go with the thickest/stiffest rear sway bar only and see how it is. If I am oversteering or something, then I will add the front one.
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Old Dec 11, 2008 | 11:13 PM
  #34  
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Originally Posted by qwikredline
well heck based on your old daytona then the 38 mm front bar on the Z06 i just built should be fine lets scrap the pansy 29mm bar. comon this is a totally useless thread now imho
wow, good thinking there buddy... comparing is waht I was doing. almost same weight damn near same weight distribution. so where are you coming from with this 38mm bar? of course thats to big. if you read my post again I state the 29 will make the car feel quite balanced and then compared to my other car of almsot same weight and distribution but a slightly bigger bar
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Old Dec 11, 2008 | 11:37 PM
  #35  
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Originally Posted by cereal83
Well I will put my 2 cents in:

I started going to the track and I noticed I would go to turn hard but I would understeer. I wanted to fix this. I had a 06 Civic Si with a stock 19mm rear sway bar. I bought a 22mm rear sway bar along with a front sway bar. I noticed right away with the rear only installed, when I went into a corner, my rear end got whiped around feeling like I was going to oversteer around the corner but never did, it just through me into it.

I then put the front sway bar on and then I notice I was understeer alot once again and that was because the front was so stiff. I took the front sway bar off and test drive it without and it was even better and would into the corners even better.

I ended up keeping the new rear sway bar, put the stock one back on the front and thats how it was until the day I sold it.

Just my experience.

I think on my SS, I am going to go with the thickest/stiffest rear sway bar only and see how it is. If I am oversteering or something, then I will add the front one.
Theres a turn by me that I periodically notice understeer at but since I put the rear sway bar on it hasn't been as bad. I know I'm driving just the same but after I make the turn i'll realize and go, "heeeyyy... not bad." lol
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Old Dec 12, 2008 | 01:29 AM
  #36  
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since some are comparing, my old cavalier (86 z24) came factory with 30mm front and 21mm rear. i upgraded to addco 30mm and 24mm, but both were chromoly. the car handles like a go-kart, not a hint of body-roll whatsoever. however, i would never do that on a cobalt. suspention technology has come a long way since then, you dont need huge swaybars to make the car flat. i honestly think an even upgrade on the bars just to reduce body roll is all thats really needed. i find my car on h&r springs is fairly neutral.

i also agree, a 29mm bar is just too big in the front. a 1" hollow bar sounds like a good upgrade as long as its comlemented with an apropriate rear bar. keep in mind with such a big swaybar it will put a lot more stress on the links, and i havent seen a decent upgrade that peope havent had problems with as of yet.
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Old Dec 12, 2008 | 01:45 AM
  #37  
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Originally Posted by cruisn
how can 29mm be to stiff? it should handle pretty damn good with it. damn near perfect balance. my old daytona had a 32mm fornt bar... and it was nicely balaced. so I cant see a 29mm on these cars being to much... I will test when I order one.
Originally Posted by cruisn
wow, good thinking there buddy... comparing is waht I was doing. almost same weight damn near same weight distribution. so where are you coming from with this 38mm bar? of course thats to big. if you read my post again I state the 29 will make the car feel quite balanced and then compared to my other car of almsot same weight and distribution but a slightly bigger bar
You are applying a set of math specifically designed for one car and try to apply it to a different car solely because they "almost have the same weight damn near same weight distribution"?

Roll stiffness of a car does not come from the ARB alone.

If you know how the stiffness of the ARB for a particular car is determined, how they are calculated and how many different variables you fail to mention are involved, you will not make that statement.

Good luck.
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Old Dec 12, 2008 | 09:17 AM
  #38  
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Originally Posted by Maven
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.
hmmm would it be an issue of less traction in the back? wouldn't a stiffer bar help it stay planted cuz there is no roll? thanks for the info and tips.
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Old Dec 12, 2008 | 09:32 AM
  #39  
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@Quickredline, since i know you're watching, i'll take a chrome moly rear sway
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Old Dec 12, 2008 | 10:03 AM
  #40  
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Originally Posted by ls1fbody
@Quickredline, since i know you're watching, i'll take a chrome moly rear sway
copy no problem; I have 1 inch here (25 mm) I use an 1.25 and the time attack used 1.50. I found the 1.50 too big, the 1.25 I found a lot of trail throttle oversteer in the rain (you can always power out of it ) and maybe the 1.50 would probably work best if the car was a lot lighter, and you had spherical joints in the rear twb pivot. I have not put twb spherical joints into my Redline for street/track test yet, like the GA Koni cars and the Time Attack all have installed . So ideally, 1.25 i think.

All these things - bars, shocks and the twb itself interplay with roll stiffness and roll center height the roll center ht keeps moving around due to the rubber pivot mounts, it makes calculations difficult and consistent handling hard to find. The initial oversteer I found in the rain when i first installed the rear arb changed over time as the pivot joints yielded and got squished and hammered and degraded. Sounds like my gf

The Time Attack car I thought really bounced a lot at the back; Heinricy didn't care he had a race to win & it was showtime, and he just drove the bitch hard off the front axle period.

I am sure (know) that the TA shock damping was not as good as the 06 road race valving, and the 08 latest stuff worked off the 7 post rig and a lot more track testing is the best, each year the shock development improved. Now that GM are gone that development curve has stopped, but the results have been pretty darn good I must say.

Good shocks cost about 5k the set of 4 for Konis, Ohlins were 7 k...another deep breath

Originally Posted by Don Juan
hmmm would it be an issue of less traction in the back? wouldn't a stiffer bar help it stay planted cuz there is no roll? thanks for the info and tips.
as a rule of thumb, crude generalization and analysis:
the arb's work the opposite ends of the car:
rear bar keeps front end planted so front sticks more than rear, therefore car oversteers call it loose.
front bar keeps rear wheels planted therefore rear sticks more than front, understeer call it push.

Originally Posted by rocketpunch1221
You are applying a set of math specifically designed for one car and try to apply it to a different car solely because they "almost have the same weight damn near same weight distribution"?

Roll stiffness of a car does not come from the ARB alone.

If you know how the stiffness of the ARB for a particular car is determined, how they are calculated and how many different variables you fail to mention are involved, you will not make that statement.

Good luck.
Ding....

Originally Posted by Sharkey
since some are comparing, my old cavalier (86 z24) came factory with 30mm front and 21mm rear. i upgraded to addco 30mm and 24mm, but both were chromoly. the car handles like a go-kart, not a hint of body-roll whatsoever. however, i would never do that on a cobalt. suspention technology has come a long way since then, you dont need huge swaybars to make the car flat. i honestly think an even upgrade on the bars just to reduce body roll is all thats really needed. i find my car on h&r springs is fairly neutral.

i also agree, a 29mm bar is just too big in the front. a 1" hollow bar sounds like a good upgrade as long as its comlemented with an apropriate rear bar. keep in mind with such a big swaybar it will put a lot more stress on the links, and i havent seen a decent upgrade that peope havent had problems with as of yet.
powergridinc.com droplinks are the best no doubt...

Last edited by qwikredline; Dec 12, 2008 at 10:03 AM. Reason: Automerged Doublepost
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Old Dec 12, 2008 | 10:15 AM
  #41  
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Originally Posted by Don Juan
hmmm would it be an issue of less traction in the back? wouldn't a stiffer bar help it stay planted cuz there is no roll? thanks for the info and tips.
Yes it is an issue of reduced traction. Besides limiting body roll the key feature of a sway bar, which is what I have been trying to help people understand, is that it is designed to reduce traction on the end of the vehicle it acts on. Look over my first post again, I thought I made i fairly clear whats happening, but heres the short version:

A sway bar lifts UP on the inside wheel in a turn. It reduces the amount of ground contact the inside tire has The stiffer the sway bar, the more dramatic this effect will be.
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Old Dec 14, 2008 | 07:22 PM
  #42  
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Heres a little pic I drew up, it show how the sway bar reduces traction. This car is turning left, the yellow arrow points that way. On a LH turn we know the car is gonna roll to the right, and push down on that side of the sway bar, as well as compress the spring, forcing the tire into the ground, a good thing. We can also see how the sway bar(red) which is conected to both struts is actually keeping the left side spring compressed, not allowing spring to keep wheel in contact with ground/lifting the left tire up. The stiffer the bar the more dramatic this reduction in tire contact/traction will be
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Old Dec 14, 2008 | 07:52 PM
  #43  
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Good post Maven.

So what it sounds like to me, is that before messing with sway bars, you want to get your car's suspension set up first.

IE if you are gonna get sportlines, get those first and see how the balance is.

If you like a slight oversteer, get a rear bar. Slight under, get front. But not huge bars.

Makes sense to me. Thanks for the explanation
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Old Dec 14, 2008 | 08:10 PM
  #44  
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Originally Posted by Maven
Heres a little pic I drew up, it show how the sway bar reduces traction. This car is turning left, the yellow arrow points that way. On a LH turn we know the car is gonna roll to the right, and push down on that side of the sway bar, as well as compress the spring, forcing the tire into the ground, a good thing. We can also see how the sway bar(red) which is conected to both struts is actually keeping the left side spring compressed, not allowing spring to keep wheel in contact with ground/lifting the left tire up. The stiffer the bar the more dramatic this reduction in tire contact/traction will be
that made perfect sence. now the stupid quesion. why on earth would you want to lift up the inside wheel?
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Old Dec 14, 2008 | 09:16 PM
  #45  
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Duh

Originally Posted by ilovecars
that made perfect sence. now the stupid quesion. why on earth would you want to lift up the inside wheel?
i think its time for me to chime in good buddy dont take offense: DUH! If the damn smilies would work i would make duh bigger and rofl cheers

Originally Posted by Maven
Heres a little pic I drew up, it show how the sway bar reduces traction. This car is turning left, the yellow arrow points that way. On a LH turn we know the car is gonna roll to the right, and push down on that side of the sway bar, as well as compress the spring, forcing the tire into the ground, a good thing. We can also see how the sway bar(red) which is conected to both struts is actually keeping the left side spring compressed, not allowing spring to keep wheel in contact with ground/lifting the left tire up. The stiffer the bar the more dramatic this reduction in tire contact/traction will be
SO NOW do a drawing that shows the reduction of body roll from the front bar keeping the rear wheels on the ground lol

Last edited by qwikredline; Dec 14, 2008 at 09:16 PM. Reason: Automerged Doublepost
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Old Dec 14, 2008 | 09:21 PM
  #46  
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Originally Posted by calhoun1
Good post Maven.

So what it sounds like to me, is that before messing with sway bars, you want to get your car's suspension set up first.
Yes.

You need to determine what kind of ride you want for the car, then you can determine the spring rate that will provide that ride. Once you got the spring rate, you then determine what kind of roll gradient you want for the car. With the roll gradient picked and the spring rate you can then calculate (combined with other variables) the required roll stiffness for the ARB.

I had a post similar to what you are wondering: https://www.cobaltss.net/forums/suspension-67/need-help-some-stock-lnf-fe5-suspension-data-145567/

Originally Posted by ilovecars
that made perfect sence. now the stupid quesion. why on earth would you want to lift up the inside wheel?
No one wants the inside wheel to life off, it is a side effect or trade off when providing roll stiffness for a car. This is exactly what Maven is trying to say all long and all race car engineer strive for. Too much or too stiff is not better, a car is a system and the art of set-up or tuning is to "proportion" the different components "appropriately" to derive a "balanced" system for a specific application.

Last edited by rocketpunch1221; Dec 14, 2008 at 09:41 PM.
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Old Dec 14, 2008 | 11:59 PM
  #47  
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k I'm getting all this to make sense more now. It has helped, But wouldn't the stiffer bar in the rear be ideal for most stituations, autox and daily driving. I mean i like oversteer better than under, and i'm sure that oversteer would be better for autox with less push from the car, meaning better turning, faster times. And yes i see how there is a lift on the inside wheel, but would it be a safety issue with the wheel coming off the ground completely? I am lowered two inches too so that would lower the center of grav. and weight transfer too so that should lessen the amout of traction being lost too right? Also Going with the Theory the bar effects the opposite side it acts on, wouldn't the ttr only benifit fwd cars more keeping the front tires both planted?
thanks for the info. I just don't want go with the stiffer is better idea and have it end up being some thing that hurts more than helps.(ttr rear bar)
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Old Dec 15, 2008 | 12:48 AM
  #48  
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Originally Posted by Don Juan
k I'm getting all this to make sense more now. It has helped, But wouldn't the stiffer bar in the rear be ideal for most stituations, autox and daily driving. I mean i like oversteer better than under, and i'm sure that oversteer would be better for autox with less push from the car, meaning better turning, faster times. And yes i see how there is a lift on the inside wheel, but would it be a safety issue with the wheel coming off the ground completely? I am lowered two inches too so that would lower the center of grav. and weight transfer too so that should lessen the amout of traction being lost too right? Also Going with the Theory the bar effects the opposite side it acts on, wouldn't the ttr only benifit fwd cars more keeping the front tires both planted?
thanks for the info. I just don't want go with the stiffer is better idea and have it end up being some thing that hurts more than helps.(ttr rear bar)
There is such a thing as excessive oversteer. Again the key is to find a balance to suit a specific application.

Last edited by rocketpunch1221; Dec 15, 2008 at 12:03 PM.
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Old Dec 15, 2008 | 09:36 AM
  #49  
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Originally Posted by rocketpunch1221
There is such a thing as excessive oversteer. Again the key is to find a balance to suite a specific application.
?................. ?
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Old Dec 15, 2008 | 06:19 PM
  #50  
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Originally Posted by qwikredline

SO NOW do a drawing that shows the reduction of body roll from the front bar keeping the rear wheels on the ground lol
I cant display both axles at once yet........:dancingpickle: I am trying to figure out a way to get it to show corner weights though, once I get that, youll get your damn drawing

I would like to know how it is that so many people have to come "like" oversteering?

What are you guys that like this handling trait driving that allows you to make this claim?

How do any of you defend "snap" and "trailing-throttle" oversteer as desirable or safe handling dynamics for a road going car?

Last edited by Maven; Dec 15, 2008 at 06:19 PM. Reason: Automerged Doublepost
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