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Discussion Starter #1 (Edited)
It's my understanding that the stock RS's have a 19mm front sway bar and a 13mm rear sway bar, is this correct?

Next, if I undertand it correctly having a smaller rear bar will cause understeer and a larger rear bar will cause oversteer, is this correct?


If so which of the following options would you recommend for a daily driver car:

Option 1 (Cheap) - Keep the stock 19mm bar in the front and replace the rear with a FHI 18mm bar.

Option 2 (better handling, more cost) - Replace the front bar with a Whiteline 20mm bar and replace the rear bar with a Whiteline adjustable bar set at 20mm.

Option 3 - Make your own suggestions within reason (around the price of option 2)


No matter which option I end up using I will probably get Kartboy rear droplinks also.
 

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overdeveloped beater
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Keep the front bar and put the adjustable rear bar on. Set at 20mm.
 

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a smaller rear bar will cause understeer and a larger rear bar will cause oversteer, is this correct?
as a general rule of thumb but there are lots and lots of variables (both mechanical and driver related) that determine the behavior of the car.

basically, i'd agree with Storm, although you may just want to get the FHI 20mm bar which is cheaper then the whiteline, though not adjustable. its actually what the suspension was designed to work with but SOA figured american drivers need understeer cause they suck, so they threw on the 13mm bar instead.
 

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Of course!! They figured any system(good ol DMV) that allows soccer moms to drive huge SUVs and allow them to rear-end into car enthusiasts can't be good. I guess we can blame the auto manufactureres that lobby for way easy driving tests from the DMV so that eveyone can have a SUV.


Ben
 

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99 2.5rs black dimond pearl
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I have your option 1 setup right now, and it is decent (definatly way better than stock),but I still get some understeer at autox. I am getting your Option 2 for xmas so I will let you know the difference in about a week.

Anthony C
 

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Discussion Starter #6
Thanks for the tips guys, I have learned quite a bit from hanging around here and this is just another example of that. The only reason I was cautious was that I read an article somewhere about the cons of having a larger rear sway bar (compared to the front) and it worried me. That's why option one listed an FHI 18mm instead of the 20mm which is the same price.

Given the cost and the recommendations for the 20mm I will probably go with the FHI 20mm bar since I only plan to replace it once and I'm not worried about adjustability. I probably should have listed that one in my option two also but my brain was in lala land or something. ;)

Hopefully I can divert some of my upcoming tax return towards my intended suspension mods. I'll have to wrangle it away from my fiance though as that money is earmarked for our wedding. If I can swing it I will probably do the rear sway bar, rear droplinks, anti-lift kit and maybe the STi engine and tranny mounts.

My plan is to start small and work mainly on the suspension and then maybe move on to an upgraded short block and heads before I get into any big power mods.

Thanks again! :)
 

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Discussion Starter #7
Bobalouy,

Cool I'd like to hear about that once you try them out. Even though I will probably go with the FHI 20mm rear bar I still might upgrade the front bar to the Whiteline 20mm somewhere down the road.
 

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smaller front bar?

I heard that you can also get a thinner front sway bar (15 or 16 mm I think).
I have no idea where you could get one, though. I wonder
how handling would be affected.
 

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Re: smaller front bar?

sunnys25 said:
I heard that you can also get a thinner front sway bar (15 or 16 mm I think).
I have no idea where you could get one, though. I wonder
how handling would be affected.
you might understeer less, but you'd go way slower. you need more roll resistance, not less, especially in the front. the only people i know who dislike beefy swaybars (and really, swaybars at all) are the rally folk. on gravel, you want your suspension to be as independent as possible thanks to the unevenness of the surface. body roll is also less of an issue since you can't pull the massive lateral g's that you can on tarmac. plus, what roll there is is helpful to rotate the car.
 

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overdeveloped beater
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Re: smaller front bar?

sunnys25 said:
I heard that you can also get a thinner front sway bar (15 or 16 mm I think).
I have no idea where you could get one, though. I wonder
how handling would be affected.
Traction would be increased at that end, though roll resistance and for all intents and purposes cornering ability would be reduced for "onroad type" cornering. Gravel or dirt cornering would probably be helped by this as posted earlier.

You can find a smaller front bar on an L model Impreza. Wanna trade me for one?:biggest:
 

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09 Legacy spec.B + 01 2.5RS
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physics

Can anyone explain better what swaybars do physically? I can't quite figure out the mechanics they affect, other than the popular idea they reduce body roll. To an extent, won't less body roll hurt cornering? Typically I would think one would want the car to tilt into the corners to an extent. I've heard many people say that a higher flow exhaust and larger swaybars are the best things you can do to a stock RS, just to basically give it the performance it's really engineered to have, sans the environmental and cost cutting measures employed which harm it's natural performance..
 
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