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Discussion Starter #1
2004 wagon. Suspension mods: H-brace, RSB (progress, adjustable) Front and rear strut tower braces. Solid links, all around. I'm really interested in getting the best street handling I can. I spend alot of time on twisty mountain roads, I want to get the best setup I can for these conditions.

I'm thinking of adding a wagon specific front bar.

First the question. Anyone swap the front bar with prodrive springs? or with springs of a similar rate? Wagon or sedan?

Background for the question.

In browsing about there seems to be 2 schools of thought on this.

I know it's a balance issue between the 2 sway bars to create a more neutral car. I'm pretty neutral now with the RSB on the lowest setting. So it appears on the surface that stiffening the front will really accomplish nothing, because I'll cancel it's effect (understeer) by stiffening the rear, again resulting in a neutal car.

In hunting around, I find there are 2 schools of thought.

1) Thick bars, loose springs.

2) Thin bars, tight springs.

It also seems that option 2 is more favorable. Why is this? NVH? performance?

I'm going to run prodrive sprngs. In my mind these springs are in the middle. They are stiffer than stock, but definetly not bone jarring. Will it help cornering/handling/feel to add the FSB?

Any thoughts are appeciated.
 

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Sway (anti-roll) bars serve two primary functions- they increase (or decrease) roll stiffness depending on size. As they do this it influences overall handling ie under/oversteer/neutral.

The "penalty" of too much sway bar is that it inhibits the independence of your suspenion (left/right)- not much of a concern on a relatively smooth surface, more of a concern on bumpy/irregular surfces.

For example rally cars use very small (or no) swaybars.

You can also influence roll stiffness w/ spring rates (as well as overall handling characteristics)- that is why you'll see some very (very) firm rates on some race cars (while using the smalles sway bar possible)- I beleive F1 cars would fall into this catagory.

What many believe is that increasing the front sway bar (and increasing roll stiffness at that end) doesn't impact overall handling as much as first maybe was thought due to improving camber change (decreasing this change). This improves front grip (less camber change) and thus would not dial in any understeer.

My persoonal experience w/ many different sway bar setups- 20/20 sedan, 21/22-24 sedan, 19/20 sedan, 19/19.5-21.5 sedan, 20/17 wagon, 20/20 wagon, 20/21 wagon- is that for gravel/rough roads- smaller swaybars work better and w/ a similar rate f/r; that bigger bars do help w/ roll on smoother surfaces, but get a little "skippy" w/ bumpier conditions.

I think balanced oe near balanced bars front/rear that aren't overly big, suits my needs best (canyon/mtn carving, autox, rallyx, track days). It's always a compromise when asking a car to perform in such varying environs.

I'm going to try a 21mm front bar this upcoming season (w/ 21m rear bar). I'll lose some rotation (I think), I'll lose a little indepndence as well- I should lose some camber change up front- which may out weigh the others.

One thing I've found out for certain is there is no "perfect" saybar combination- too many factors/variables come into play- one of which is a driver's preference- somebody's oversteering car could be somebody's elses understeering pig.


Experimentation is the only sure way to find out what works best for you :)

Big Sky
 

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Discussion Starter #3
Who makes the 21mm wagon bar? I was thinking about the 22mm whiteline. I really have no desire to go with really stiff bars, because of the loss of independence. I was thinking that the FSB is more of a tweak than the RSB, which is a fairly dramatic difference. I was thinking go with the 22mm and up the rear bar one notch.


The problem with all this is of course, is that the other suspension pieces must also match. Did you play around with different springs with those bar setups?

I'm thinking ahead here. When I finally get to an FSB, I will have added an ALK( sport) and prodrive springs. What I think will work best for me is to have fairly low rate springs on a reasonably stiff chassis.
 

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I agree for what your doing/planning a super duper big bar makes no sense.

I'm running GC front aluminum arms which I have found out the sedan front sway bar fits much better than the wagon one- so I'll be going w/ the STi 21mm sedan front.

I'm pretty sure Cusco makes a GC (turbo version) 21mm front bar that should be a perfect fit for the wagon- try gruppe-s- I'm pretty sure it will be a special order item.

Otherwise the 22 front bar w/ your rear bumped a notch will work as well.- it may take a little experimenting w/ your rear bar settings to get the best match to the front.

Big Sky
 

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Discussion Starter #5
Sounds like a plan. I think I'll try the 22 mm bar and go one more notch in the rear. If that fails I'll start looking at the 21mm options.

Thanks fo the input!
 

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I'm Looking at Same Thing

2003 WRX Wagon. After a year off from modding, I'm returning to address the suspension issues, especially since I'm going to start auto-x this year in STX.

I've done a couple of track days the last two years and noticed the plowing understeer I had my first trip was not as bad on my second trip to the track after I'd installed a sedan rear bar. But, I still had lots of body roll.

My first step in addressing my suspension will be wheels/tires (probably Enkei RPF-1 17x7.5 with 225/45/17s), but after that I'm thinking about upping both front and rear swaybars to a Whiteline (20,22,24) adj in the rear and either the same in the front (resulting in 22r 20f) or a Cusco 21 for the front (resulting in 22r 21f). I'm really not sure what my stock front bar is, I see both 19mm and 20mm quoted.

My eye is on the Whiteline Group 4 coilovers for the long term target, but that will have to wait for next year.

End goal is best road car handling for my daily driver, plus my once-a-month summertime auto-x or track days.

I've already spent way too many hours searching these forums, but am still looking for a well-defined, incremented upgrade path for my end goal.

Any help is appreciated.

B
 

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wv_wagoneer- sounds like a good plan, let us know how it works out. Sway bars are definitely one of those things that takes some experimenting- the good thing is if they don't work, they're easy to resell.

Bart- your goals sound pretty close to mine, look through my project wagon thread- some good discussion on wagon specific suspension and brake needs. Your on the right start IMO- wheels/tires, sway bars (I'd throw alignment in there as well), then probably struts/spring or coilovers, then you can get into bushing upgrades and chassis stiffening.

You probably know this already, but brakes need to be adressed up front for track days- fluid/pads at a minimum.

Mike
 

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Look at camber/caster plates

Bart - to dial out that understeer many of us have installed camber/caster plates in front. You can only get so much negative camber from the camber bolt up front. The Noltec plates provide much more camber and caster, which improves turn in. If you're planning on installing coilovers that's a good time to add the plates. More negative camber eliminates the downside of a larger front sway bar on the race track. Once it's all in place, the car is so much fun.
 

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I'd agree- there is more than one way to skin a cat :)- increasing positive caster and neg camber up front is a win/win- better grip in corners, dials out understeer.

Also increasing rear spring rates in relation to the front will also dial understeer, while reducing body roll- another win/win. The oe setup runs ~ 168 front/ 120 rear for spring rates- you'll see most coilovers and even oe STi springs get much closer to a even rate front rear for ex oe STi v7 188/173, v7 RA 217/192, v8 STi WRX pinks 223/195, Prodrive runs the same rate front/rear (their v7's anyways)- you can see the pattern.

Big Sky
 

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Thanks!

You can read all the threads, but often there's some conflicting opinions/advice.

AFA increasing spring rate goes... which springs serve best with the oe MY03 struts on a wagon? I'd seen the recommendations for the Prodrives and the STI pinks (lowering?), but I'd also seen some v8 JDM STI DCCD takeoff springs (I assume these are non-lowering) for much less money. Don't I reduce travel (a negative effect) if I simply put on shorter (lowering) springs?

But, I'd read about valving issues with the oe struts combined with some springs causing bounciness at normal (off-track) speeds and that's not a tradeoff I'm willing to make. Especially if I'm just going to pull them off in a year when I install a full coilover or strut/spring solution. But, I guess you could always sell 'em.

AFA adding negative camber in front, how much farther do you go past -1 to -1.5 without negatively affecting high-speed straightline stability (i.e. w/o making the car squirrely)? Is it primarily the change in castor that's a benefit from the Noltecs? My understanding is that more positive castor is a win/win, and by using the Noltecs I add positive castor while avoiding the STX restriction on the ALK (which also adds positive castor)?

Thanks,
B
 

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I agree you do see a fair amount of contradictary statements.

The STi takeoffs will lower, but only ~ 10mm. The Prodrives IIRC a little of a inch. The STi takeoffs have higher spring rates, the Prodrives probably a better match for the oe struts (they were designed around the oe strut- the STi around the STi strut). There is an issue w/ using v8 springs w/ v7 struts as well. They make a v7 pink lowering spring as well- but again the springs were designed around the STi inverted strut.

Lowering will reduce suspension travel, but the Prodrives are a relatively mild drop- so I don't too much of a ill effect. The fact that your slightly firming rates and lowering your CG would outweigh those concerns (unless you do a lot of "gravel" work).

-1.5 (even -2.5) won't hurt straight line stability (a very small smidge in braking, but easily compensated by improved grip in cornering). Toe effects straight line stability a lot more than camber, thus my general recommendation on 0 toe f/r.

The Noltecs are STX legal, where the ALK is not- the Noltecs give you ~ 1.5 degrees of caster gain the ALK ~ 0.5, the Noltecs also give you ~ 1.0 degree of additional camber- obviously the ALK nothing. Hard to say which is more advantageous the camber gain or the caster gain- both are good.

The Noltecs run around $250, don't know what the ALK runs.

Mike
 

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Discussion Starter #12
A couple of things sort of related.

1) I'm debating camber plates on prodrives/stock my04 struts. If my application is soley street, do I need them? What front camber can I expect without them? I don't use the car for long trips on the highway, and I'm almost always on twist roads. What fornt camber would be reccomended?

2) What about rear camber? If I install camber bolts in the rear on that setup. Should I put them on positive or negative, in order to achieve what I need?
 

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I really don't think you need camber plates up front for street use only. You can get about -1.5 up front which is enough on the stock setup. Going less negative on the rears (with the use of camber bolts) will dial out some understeer, but when on the street, a little bit of understeer is a good thing for safety.

I had the Prodrive springs on stock shocks for 25,000 miles and I thought it was an ideal street setup. Since then, since I auto-x, I have gone with Koni Inserts woth GC Coilovers and camber/castor plates. For the street, I adjust the plates back to about -2.0 camber in the front and try to run as close to zero toe as possible.
 

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Discussion Starter #14
Bear with me...alignment specs are not my best thing lol

I guess what I'm asking is if i go with -1 in the front (prodrive specs) What should I run in the rear? I guess either -.5 or zero. What about if i went with -1.5? in the front.

I've seen people put the rear bolts on the positive side to get zero. I was wondering what value you get if you have no bolts.

Basically I have to decide on which side to put the camber bolts and what to tell the alignment guy I want. I don't mind messing with it, if it doesn't work for me. I just need a starting point.
 

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Well, without camber bolts, I was about -1.3 in the rear. My advice for your alignment would be to go max neg on the front (about -1.5), forget camber bolts in the rear for the moment and have zero toe all round. With an upgraded rear sway, I think you will love the handling. If you decide it still pushes too much (which I truly doubt for a street setup), either adjust the rear sway or get camber bolts for the rear and go more positive.
 

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I'd agree- bump up the front to as high as they can get- ballpark -1.3ish, leave the rears and run 0 toe.

If you find you need additional understeer dialed out (or if for some reason you end w/ excessive neg rear camber- say -1.7+ or bad rear cross camber- say more then 3/10ths side to side) then consider camber bolts for the rear. I like about 0.5 - 1.0 difference in camber from front to rear. Running -0.8 to -1.0 in the rear should be just about right w/ -1.3ish up front. You don't want to go too low (too positive) in the rear- the rear tires still need some neg static camber in them- I would never run less than -0.8.

Mike
 

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front wagon sway bars is the same as sedan correct?I here there longer as the sedan is wider then the wagon. So who makes swaybars for the wagon. I have heard that white line does but I have not heard of any others. with coil overs how much sway bar should I go for for a good ride and corner ability.
thanx
 

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Your correct- same dia- 20mm, but different length's and not interchangable. Whiteline makes one for sure and I'm 99% sure that Cusco does as well- it should be the same as the GC8 turbo (jdm)

Your not going to find too much choice in dia up front 21 or 22- some bigger ones for the sedan. For the rear you'd wnat as least the same amount of bar or more- most go w/ adj bar in the rear to tune in just the right amount.

Big Sky
 

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very interesting thanx for the info
 

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Discussion Starter #20
BlkWRXWag said:
Well, without camber bolts, I was about -1.3 in the rear. My advice for your alignment would be to go max neg on the front (about -1.5), forget camber bolts in the rear for the moment and have zero toe all round. With an upgraded rear sway, I think you will love the handling. If you decide it still pushes too much (which I truly doubt for a street setup), either adjust the rear sway or get camber bolts for the rear and go more positive.
When I say "street setup" I really want a setup geared more to the twisties. I drive alot of country roads, more than anything else. Lots of hairpins and S-curves. Welcome to west virginia lol

Let me see if I can put together what you two are saying. I run ~ 1.3 to -1.5 in the front, then in the rear I run -0.5 to -0.8. To do this I would put in camber bolts to make it more positive in the rear. I have the bolts, so that's not a problem. I can go a notch up on the rear bar if I need to, right now it's pretty neutral on stock springs. I want to keep when I do the prodrives.

One thing I just thought of. When I do the alignment I will also have an ALK (sport) on. Will that make any difference?

Above I was refering to the whiteline 22mm. subaruwrxparts.com

Bob
 
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