Thứ Hai, 9 tháng 1, 2017

Rally suspension set up help for WRX? part 1

oversteer 08-31-2006 02:52 PM

Rally suspension set up help for WRX?
I am wondering what kind of suspension specs and parts WRX rally guys are using.

My understanding is that soft spring rates (under 250#), stock sway bars and very little camber is the normal route to go, assuming around a 3200lb race weight. I wonder how the cars are able to absorb huge dips, bumps and jumps with such soft springs? I doubt that the grass roots budget rally guys all using double and triple adjustable shocks with huge compression damping to keep the suspension from bottoming.

Can anyone shed some light on this subject :confused:
John Vanos 08-31-2006 02:59 PM

The softness is precisely what allows the cars to take those big hits....We let the suspension do the work of moving which allows the car to come away unscathed. Rally suspension has a lot of travel combined witht eh softer springs whihc allows it to take the bumps with ease. I think you wil lfind most rallyists have good suspension (adjustable, strong etc) as that makes a huge difference to your speed. It is much better to spend $5000 on some great suspension over a new fancy motor

Little camber is also correct as rallying does not see the same extreme cornering loads on the tires
RB5 Clone 08-31-2006 03:51 PM

RS-spec 2.5 GC8, race weight 2700#

spring rate 285# all 4 corners, w/ 50mm DMS gravel spec struts

those big fat shocks can absorb some serious abuse. dialed up ride height over stock a bit for extra susp travel. rides like a buckboard at low speed, but once you're doing 40 down some little rough dirt road, it all smooths right out. at 60-80 you wouldn't believe what the car will float over!

camber is -1.5 to -2 up front, w/stock toe-in

-1 camber @ rear, w/zero toe. you can get more camber at back with DMS 50s, but often run into clearance issues with 205-65-15 gravel tires hitting the spring perches.

Dave G
DMS Fan
Easy Rider 08-31-2006 05:03 PM

Um . . yea what he said /\ /\.
That is almost the exact same set up on my car.
John Vanos 08-31-2006 05:18 PM

285 LB springs? hmmmmm I run 250's....I use the same alignment as you do Dave but minus the toe in, why do you have that?
OBShahn 08-31-2006 05:27 PM

[QUOTE=John Vanos;15091881]285 LB springs? hmmmmm I run 250's....I use the same alignment as you do Dave but minus the toe in, why do you have that?[/QUOTE]


In theory toe out can aid in the ability to turn in but toe in should, atleast a little bit, lead to slightly higher stability at high speeds (less liekly to dip/dodge/bounce around in ruts and what not).

I know of a variety of teams that run 0 or toe out in the front but toe in in the rear for stability at higher speeds.
John Vanos 08-31-2006 10:03 PM

Ya, my thought is run 0 toe all around and then make the car handle the way I want via other methods

I guess its just personal preference
OBShahn 08-31-2006 10:20 PM

[QUOTE=John Vanos;15095054]Ya, my thought is run 0 toe all around and then make the car handle the way I want via other methods

I guess its just personal preference[/QUOTE]




Probably depends on the rally you are running...

At cog, high speeds mean you want the stability you don't want the back end of the car floating around...

Sounds like a plan with the alignment until you get the dampers figured out for your set ups. But don't overlook alignment, it is a very very important way to finess the behavior of the car...

It is all part of a package...


*has read too many suspension tuning and set up books despite not having a race car...
RB5 Clone 09-01-2006 10:38 AM

[QUOTE=John Vanos;15091881]285 LB springs? hmmmmm I run 250's....I use the same alignment as you do Dave but minus the toe in, why do you have that?[/QUOTE]

285#s are what came with my struts, that's why. they're a bit bouncy (esp at the back), but better since I started running bump at full soft. A full DMS rebuild is in my near future, and will probly go with softer springs.

I run stock toe-in at front 'cause I don't want to have to steer the car to make it go staight! :eek: ;)

Dave G
oversteer 01-07-2007 07:58 PM

[B]What is the general wisdom on sway bars for Rally cars? [/B]

After watching lots of WRC, Group B (old) and other footage it looks to me that none of these cars have the excessive bodyroll I would expect if they were using soft springs and smallish sway bars.

Actually, after searching I see that many people suggest the smallest bars possible or no bars at all. How can this approach maintain a good camber curve through a corner? Fast rally cars (especially WRC) can generate lots of grip/corner speed on a variety of surfaces (mostly tarmac & gravel) so I would think that soft spring rates, high ride height and soft or non-existant sway bars would add up to lots of roll and postive camber. Why do these cars stay relatively flat with such soft suspension?

My car's suspension will have to be a major compromise of abilities since it will be used as a daily driver, AutoX, RallyX and recreational type TSD and closed stage rallies. Here is what I am thinking: USDM STi struts and springs, Whiteline 24F/22R sway bars, harder bushings and camber settings of -1.5F/-1.25R.

Are there any major flaws with my planned set up? If I was to add another $1000 to the budget how would it be best spent?

Thanks :cool:
akuhner 01-07-2007 09:10 PM

That sounds fine, you'll just be pushing your luck on stock struts in a stage rally. At at stage rally you would need to have a full set of fully assembled struts/springs/top mounts ready to go at service. What would the total budget be, I don't know what you could add the $1000 to?

I had Tein HGs on my daily driver / rally-x car and they were fine on the street. The HGs got me through two stage rallies as well, but I do wish they could go firmer (I tend to only use the two hardest settings even though they are 16 click adjustable).

WRC cars have huge sway bars, they used to be active. Baja / Dakar type cars would need tons of suspension travel while letting body roll suffer, but for rally you really need the travel to absorb the hard landings, not to keep the tires down when you go over a pot-hole or something. Handling trumps suspension travel any day.
illgod 01-07-2007 10:00 PM

hey guys i have a 02 wrx with cobb stage 2 setup recently
i have a front 22mm and rear 24mm ajustabul sway bars. i have the sti transmiton mount and front,rear and under body srtut tower bars. stanless steel brake lines. can i take my car off roading, rallyXing autoX or on a road corse? what should i upgead on it to make it more race ready and stronger. dose any one know anyware that i can take my car rallyX neer NYC? or a rally corse that i can take it on? thanx
shikataganai 01-07-2007 10:25 PM

[QUOTE=illgod;16575148]hey guys i have a 02 wrx with cobb stage 2 setup recently
i have a front 22mm and rear 24mm ajustabul sway bars. i have the sti transmiton mount and front,rear and under body srtut tower bars. stanless steel brake lines. can i take my car off roading, rallyXing autoX or on a road corse? what should i upgead on it to make it more race ready and stronger. dose any one know anyware that i can take my car rallyX neer NYC? or a rally corse that i can take it on? thanx[/QUOTE]
quoted for spelling posterity :lol:
Howl 01-08-2007 09:22 AM

[QUOTE=illgod;16575148]hey guys i have a 02 wrx with cobb stage 2 setup recently
i have a front 22mm and rear 24mm ajustabul sway bars. i have the sti transmiton mount and front,rear and under body srtut tower bars. stanless steel brake lines. can i take my car off roading, rallyXing autoX or on a road corse? what should i upgead on it to make it more race ready and stronger. dose any one know anyware that i can take my car rallyX neer NYC? or a rally corse that i can take it on? thanx[/QUOTE]

If you set your car up for gravel roads in most cases you will be making it handle worse on tarmac, and vise versa. Also if you make it more "race-ready" you're likely going to be making it less streetable. You have to decide if you want to go to one of the extremes (and which extreme), or find some happy compromise.


[QUOTE=shikataganai;16575414]quoted for spelling posterity :lol:[/QUOTE]

This isn't OT.
davis10 01-08-2007 02:06 PM

Ive heard of some people using d-specs with additional welded on support as a budget setup. Can anyone chime in on this and how it would compare to a stock STi setup??
Recce01 01-08-2007 03:44 PM

[QUOTE=davis10;16582607]Ive heard of some people using d-specs with additional welded on support as a budget setup. Can anyone chime in on this and how it would compare to a stock STi setup??[/QUOTE]

They are virtually unbendable :)
Recce01 01-08-2007 03:50 PM

case in point
.........
[IMG]http://images16.fotki.com/v303/photos/1/12634/3499629/rim3-vi.jpg[/IMG]

and these same reinforced D-Specs have been given away, and they are still going strong on a GC8 rally car!
davis10 01-08-2007 04:12 PM

^^^^ Thats the picture I had in mind :-) any other info on that setup for suspension and reinforcement? besides cage and seam welding.
akuhner 01-08-2007 07:48 PM

[QUOTE=illgod;16575148]hey guys i have a 02 wrx with cobb stage 2 setup recently
i have a front 22mm and rear 24mm ajustabul sway bars. i have the sti transmiton mount and front,rear and under body srtut tower bars. stanless steel brake lines. can i take my car off roading, rallyXing autoX or on a road corse? what should i upgead on it to make it more race ready and stronger. dose any one know anyware that i can take my car rallyX neer NYC? or a rally corse that i can take it on? thanx[/QUOTE]

Of course you CAN rally-x or auto-x your car (you can auto-x virtually any car on the road), the question would be do you want to. As always, the rule of thumb for a newbie is not to make any modifications at all if your goal is to be more "race-ready" for auto-x or rally-x. Your car was born ready, it's the nut behind the wheel that needs upgrading (nut behind wheel = you). Before you spend a dime on "race-ready" parts put a year or so into attending events - after you've competed for a season or so you'll know what race parts are worth the effort.

Note that for rally-x you can safely invest in a skid plate and mud flaps.

To find a rally-x near NYC check out [url]www.rallynewyork.com[/url] and [url]www.ner.org[/url], for auto-x check out [url]www.autox4u.com[/url].

Sorry for participating in the thread-jack!

Alex
AlbaScoob 01-09-2007 07:50 AM

[QUOTE=oversteer;16573972][B]What is the general wisdom on sway bars for Rally cars? [/B]

After watching lots of WRC, Group B (old) and other footage it looks to me that none of these cars have the excessive bodyroll I would expect if they were using soft springs and smallish sway bars.

Actually, after searching I see that many people suggest the smallest bars possible or no bars at all. How can this approach maintain a good camber curve through a corner? Fast rally cars (especially WRC) can generate lots of grip/corner speed on a variety of surfaces (mostly tarmac & gravel) so I would think that soft spring rates, high ride height and soft or non-existant sway bars would add up to lots of roll and postive camber. Why do these cars stay relatively flat with such soft suspension?

My car's suspension will have to be a major compromise of abilities since it will be used as a daily driver, AutoX, RallyX and recreational type TSD and closed stage rallies. Here is what I am thinking: USDM STi struts and springs, Whiteline 24F/22R sway bars, harder bushings and camber settings of -1.5F/-1.25R.

Are there any major flaws with my planned set up? If I was to add another $1000 to the budget how would it be best spent?

Thanks :cool:[/QUOTE]

We've played around all year with suspension settings at a huge variety of events.
We have stock springs (soft and good ride height), stock top hats, adjustable KYB AGX shocks, adjustable rear sway bar & links and this set up is perfect for street, TSD, occasionaly track playing, autox and rallyx. The car is competitive in STX & PA classes having won several events last year and finished second in PA class in our region for 2006 behind an 06 STi. I would not use this setup for gravel stage rallies as its just too stiff and would advise a 2nd set of struts. Although we did run the car at POR last year and didnt have a problem. Tarmac rally might be a different story however and they may be suitable. We plan on keeping them for that reason once we switch to a gravel setup.
24F/22R sway bars will make your car understeer like a dog on gravel. Thats why we kept the stock one on the front and tightened up the rear to get good rotation at low speeds. For the same reason some guys remove the front bar and leave the stock bar for stage events. I actually use almost the same settings for rallyx as autox just one click softer on the AGXs. I soften everything up for TSDs and regular street driving and the car still feels really responsive but not twitchy compared to stock.

Hope that helps.
randy zimmer 01-09-2007 11:02 AM

$.02
car GC 2.5RS
F/R
275#/225#
DMS
toe out/in
camber -/+
no bars = side bite
also...
bars make repairs harder and longer.
for those who think setup is king, imagine perfect bars may = 1 sec./mile
Nat'l rally = 120 miles... 2 minutes gained
F A-arm replacement at service, 2 min late = 20 sec lost - total now 100 sec gained.
rear shredded tire stuck in bar, needed to remove link to get tire loose, 5 min lost on stage = -3 min. total = rally over
(and with the rear bar off, I couldn't tell the difference.)
rz
RB5 Clone 01-09-2007 05:59 PM

my RS rally car Tulip is set up almost exactly like rz's except for one (brief) experiment, adding a 22 mm rear bar w/race endlinks scavenged off a crashed WRX

new fat rear bar + pendulum into hard R uphill = snap oversteer = severe deceleration/pine tree

At least I missed the Porta-Potti.

leave the rear bar OFF for gravel play.

BTDT:rolleyes:
Ralliart4 01-09-2007 08:40 PM

Cough cough.... look up your handy dandy FIA Gp.N rally car specs and that is the best balance you can get.

Look it up and you should be able to bend the balance to alow you to have a fair car and still decent enough to drive to work.
Jard 11-08-2007 12:25 PM

Going to bump this.

I am currently prepping my '02 WRX Wagon for SCCA rally-x, PA class.

Current Setup:
KYB GR-2 Struts (wagon specific)
Stock STi springs (224f/190r - or very close to that)
RCE lowering camber plates (canted for more caster)
Group-N rear tops
Sedan front control arms
Stock sedan front sway and links
Whiteline HD rear swaybar mounts
Whiteline 22mm adjustable rear swaybar
-2.6 front camber
-1.3 rear camber
1/16" toe out front
0 toe rear
3.7/3.8 front caster

I ran 3 events this year on this setup and did well. 4th overall and 5th overall and 2nd in PA at the last 2 events.

This is only going to be for rally-x so I am willing to make sacrifices for the street.

I am considering switching to '04 STi struts with stock WRX wagon springs (already have the struts) to get some height back. I am definitely going to get a set of camber plates that don't lower the car.

Thoughts? Less camber?


Here's video from the last event...
[url]http://www.youtube.com/watch?v=cvS7hd96B24[/url]
Fred 11-08-2007 12:40 PM

[QUOTE]I am considering switching to '04 STi struts with stock WRX wagon springs (already have the struts) to get some height back. I am definitely going to get a set of camber plates that don't lower the car.
[/QUOTE]

That would be awesome for rallyx. Softer springs, more bump travel and much better damping. Same setup I ended up with on my RS. I use crash bolts instead of camber plates, though. A lot less expensive, and since I know what I'm doing, I haven't had any of the problems the people who don't know what they're doing have had. :) For just rallyx, you won't need more camber than what that setup will get you. And you should switch back to the stock rear bar.
Jard 11-08-2007 12:49 PM

[QUOTE=Fred;19979730]That would be awesome for rallyx. Softer springs, more bump travel and much better damping. Same setup I ended up with on my RS. I use crash bolts instead of camber plates, though. A lot less expensive, and since I know what I'm doing, I haven't had any of the problems the people who don't know what they're doing have had. :) For just rallyx, you won't need more camber than what that setup will get you. And you should switch back to the stock rear bar.[/QUOTE]
Kevin? I met you at the Oakland Acres rally-x school this year. Mark beat me by about 0.5 seconds at both our last two events.

A few of your guys came up to Summit Point last weekend and ran with us. I want to make it to one of your events some time here soon.
Fred 11-08-2007 01:34 PM

Come on down. :) Our next one will probably be in February, and the season opener is usually at my house.
WanganWRX 02-22-2009 12:02 AM

Jard bumped it after 10 months, so what's a year and 3 months...

Thanks for the input all, I'm prepping my 03 wagon... It lasted 130k miles on the stock suspension beating on dirt/gravel/snow... The car's built for it.
Jard 02-22-2009 03:22 PM

I ended up with D-Specs and stock wagon springs. Group-N tops in the rear and Cusco camber plates in the front... :D

PM me if you want more info or want to kick things back and forth...
S1MPSONS 10-15-2009 10:25 AM

Does anyone know the ride height difference between running an OE STi setup on a WRX vs a OE forester setup on a WRX?

Also, can forester springs be used on OE STi struts? Or do forester shocks have better travel?
UP2MTNS 10-15-2009 12:52 PM

nix the camber plates....added expense you don't need. I know...I had them for rallyX....and never actually adjusted them once, and never had any crazy camber angles or anything beyond what stock would allow me to do.
UP2MTNS 10-15-2009 12:55 PM

[quote=S1MPSONS;28486389]Does anyone know the ride height difference between running an OE STi setup on a WRX vs a OE forester setup on a WRX?

Also, can forester springs be used on OE STi struts? Or do forester shocks have better travel?[/quote]

you'll get more travel with forester shocks/struts, and a LOT higher ride height. search for pics, its high.

not sure about forester springs on sti struts.
aspen_rex 10-15-2009 01:21 PM

RSP, OHLIN, Proflex, EXE-TC, Reiger, BOS, if you want to compete with the top field. If you are a grassroots kind of guy look at DMS and Hotbits.
AndyRoo 10-15-2009 03:54 PM

Forester springs on STI struts would probably coilbind.

- Andrew
OBShahn 10-15-2009 06:02 PM

[quote=aspen_rex;28489146]RSP, OHLIN, Proflex, EXE-TC, Reiger, BOS, if you want to compete with the top field. If you are a grassroots kind of guy look at DMS and Hotbits.[/quote]


RS&SP is launching a new clubmen spec suspension line. Should be <$3,000.00 a set...
sniper1rfa 10-15-2009 08:26 PM

still a boatload of cash for a rallyx car.
UP2MTNS 10-19-2009 02:31 PM

[quote=sniper1rfa;28495477]still a boatload of cash for a rallyx car.[/quote]


true dat.


check this out guys...
[url]http://www.dirtyimpreza.com/forums/showthread.php?p=164595#post164595[/url]


Feal Suspension is making an insert for stock WRX struts...uses oem sprints, but the insert is adjustable and valved a little more agressively, and is adjustable.

The insert is HotBits stuff.

Not sure if he's posted costs yet.
mencius 02-26-2010 05:15 PM

Pricing is 895$

$749 for group buy of 10 or more.
REDrum 03-02-2010 09:27 PM

[quote=OBShahn;28493768]RS&SP is launching a new clubmen spec suspension line. Should be <$3,000.00 a set...[/quote]

Very beefy for the price point and service is in the US thru Rallispec. Could be used entry level stage rally strut or very nice rx strut

IMO the RS&SPs are the best value for the money in stage rally struts right now. If I didn't already own 3 sets of DMS there would be a set on my rally car.

Those inserts from Feal could prove a very good option for entry level rx too.
RallyBagger 03-03-2010 10:22 AM

i run RS&SP "value" rally struts. it took us to the podium at the Winter Rally New York

Great $ to perfomance value and they look stunning....

[IMG]http://i101.photobucket.com/albums/m42/Tbagger_photos/IMG_4073.jpg[/IMG]

[IMG]http://i101.photobucket.com/albums/m42/Tbagger_photos/IMG_4076.jpg[/IMG]

[IMG]http://i101.photobucket.com/albums/m42/Tbagger_photos/DSC_0041.jpg[/IMG]
rallynutdon 03-03-2010 01:09 PM

[quote=RB5 Clone;16601279]my RS rally car Tulip is set up almost exactly like rz's except for one (brief) experiment, adding a 22 mm rear bar w/race endlinks scavenged off a crashed WRX

new fat rear bar + pendulum into hard R uphill = snap oversteer = severe deceleration/pine tree

At least I missed the Porta-Potti.

leave the rear bar OFF for gravel play.

BTDT:rolleyes:[/quote]

Or use the wimsy (sp) stock 1st gen Impreza one, which is what I've been doing for 9 years.
JDwhiteWRX 03-04-2010 07:25 PM

Hi guys,

What do you think about running those new Feal Suspension inserts with RCE blacks in a DD car that does 3 or 4 smooth track rallyx per year, 4 or 5 autox (wet concrete) and about 5 track days?

I guess the car is a real allrounder so there is obviously going to be a fair bit of compromise with the suspension setup. Would there be any advantage with these strut inserts over tokico d-specs?

Cheers

JD.
Hyper 03-05-2010 03:31 AM

[quote=RallyBagger;29940114]i run RS&SP "value" rally struts. it took us to the podium at the Winter Rally New York

Great $ to perfomance value and they look stunning....

[IMG]http://i101.photobucket.com/albums/m42/Tbagger_photos/IMG_4073.jpg[/IMG]
[/quote]


what are the specs and pricing for those? I didn't know they come without reservoirs
RallyBagger 03-05-2010 07:37 AM

they're 2800.00 and run the standard gravel spring rates. single adjustable. same spring set up as the "big boy" one's. Same bodies as the "big boy" ones. Also come with some nice wrenches and some rear camber tools.

they really are fantastic for the price. they will become our back ups once we can afford the "big boy" setup.
Ralliart4 03-05-2010 08:45 AM

I use tein gravel coilovers... not the rally setup with the remote tank but the dirt trial setup. They are 5kg/5kg with soft bound and hard rebound.

They are pretty cost effective and almost anybody can rebuild them. As a matter of fact I use them daily and even on my tarmac setup (i just use really big swaybars) and makes the car very tossable and able to gather it when things go wrong.

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