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View Full Version : Suspension tuning/set-up for rally-x/street



ScaryFatKidGT
04-06-2010, 11:59 PM
Ok so On the street my car understeers horribly, HORRIBLY people say "oh well its a subaru" but its like really bad like if I push it over 6 or 7/10ths the thing just understeers. My friend just got a 2001 Audi A4 Sport Package and it drives on the highway just fine but has about half as much body roll as my car and doesn't understeer as bad but it is on 235's vs. my 205's. I can get my car to understeer on every corner from my house to work without going over the speed limit just about. BUT I just went to my first rally-cross and it was just fine maybe even a little to tail happy in the s-curves, I think this is because of my relatively soft suspension when the weight transfers back and forth.

I have a good deal on a 19mm rear sway but I don't wanna stick that on and have it be to hard to rally-cross.
I have contiextreamcontacts for tires there all-seasons but there not ****

As for springs and shocks I want to stay about stock height for rally-x and snow. I want it like stock STi stiffness something that will probably be a little soft on a race track but will be stiff on the street and good for rally-x.

I know a lot of companies make lowering springs and KYB makes shocks for my car but idk of any stiffer stock height springs.

decke48
04-07-2010, 01:29 AM
for springs you could try to get king springs, they offer lower, stock, and raise springs at a higher rate then oem.

ScaryFatKidGT
04-08-2010, 12:19 AM
If I replace my 4EAT tanny mount bushing are there also the tranny cross member bushings I can replace like on a manual?

rougeben83
04-10-2010, 09:37 AM
keep it stock.

ScaryFatKidGT
04-10-2010, 08:34 PM
Keep what stock? lol the whole car? I need to do something about my marshmallow bushings.

rougeben83
04-10-2010, 10:36 PM
Do you want it to still be able to tackle a rallyx course without shattering your teeth? Then don't put "rallyx" in your requirements for a suspension setup. You'll never have a suspension that is both capable on tarmac and in the dirt, they require two opposite things from the suspension. The stock setup you have now is probably the best compromise for either one, but what you really want, guessing from your "my friend's A4" comparison, is better on-road handling - by which there are plenty of threads as to how to achieve that. Pick which surface is more important and go from there, you can still make it through a rallyx course fine on a street-derived suspension, you just can't pick the fastest line sometimes and avoid the ruts that gets dug in from previous cars.

ScaryFatKidGT
04-11-2010, 01:14 AM
Well I was under the impression that even rally based suspensions were stiffer than LGT stock which would also transfer to stiffer on road. Even a base WRX suspension is a bit stiffer than any legacy and then theres the STi's that people drive on everything from tarmac to full blow stage rallyes on the stock suspension.

Most rally springs I see raise the ride height and have a %20-%30 increase in spring rate but I wanna stay as close to stock ride height as posable because If I go lower I will bottom out in rally-x and get stuck in snow but if I go up on road handling would go down, so I think some stiffer stock heigh springs and who knows what for struts, something adjustable, will help.

Also I'm pretty sure his A4 would do fine in dirt because its not even as stiff as the S4 and the S4 is still a little softer than a WRX STi or an EVO it just has like 0 body roll idk if it has huge sway bars or what but its a perfect sporty ride. (besides weighing 3350lbs)

rougeben83
04-11-2010, 02:09 PM
Yes they do increase the spring rate on rally setups, but you have to understand why theyre doing that. It's to get better weight transfer. You're partially right about keeping the thing from bottoming out. You have to be able to know how to take advantage of the stiffer setup to actually make it work.

The fact that youre understeering in the dry AND oversteering in the dirt when youre driving means you have a habit of putting the throttle down too early; that is not something bushings, springs, tires can cure 100%, it's you that has to make that change.

ScaryFatKidGT
04-11-2010, 08:29 PM
Putting the throttle down to early in the dirt?

I also have realized if I left foot brake and manually down shift the tranny I can get it to understeer a little less on the street, but I seriously do need some bushings in my front end.

ouch1011
04-14-2010, 12:45 AM
You might want to dial in some negative camber in the front for a little more front end grip. An outback rear sway bar is a good upgrade on the stock suspension too.

But the Legacy is sprung very soft in stock form, pretty typical of a mid 90s GT car. The A4 is a typical german car where it is tuned a bit more for a sporty feel and is firmer than the Legacy. It is going to handle better in stock form.

Honestly though if you want a car that has the best comprimise of pavement handing and rally-cross ability, stock is going to be your best bet. Just update the parts. The problem with building something to handle 2 very different situations is that it is going to be medocre at both. For dry handling you would want to drop the car slightly and go stiffer on the springs. For rally cross you would certainly not want to drop it and maybe even raise it slightly so you could have the suspension travel you needed to keep the tires planted.

rougeben83
04-14-2010, 12:56 AM
Ideally you shouldn't be running any sort of camber in rallyx, you need tires square and planted to the surface as much as possible for traction, negative camber aides in dry pavement turn-in and mid-turn stability with the suspension ideally statically loaded. You have ruts, bumps, and all sorts of undulations that the suspension is trying to quell mid-turn in rallyx. Like I said, pick which one is more important to you and live with what you gave up in the other.

ScaryFatKidGT
04-14-2010, 04:07 AM
So no static camber at all for rally? Sure the G-forces are a lot less on a less gripy surface but, it seem to me if you were sliding sideways you would want some camper so the tires had more contact with the outside where the dirt was piling up vs. being on the edge of the tire and to prevent your tires from buckling under the car. But then again that side of the cars suspension should be under compression causing some camber.

Will then I guess I'm looking for a stiffer stock high suspension but still streetable and there fore somewhat rally-x able. Like I said before around STi stiff, way stiffer than a legacy but lots of people still take them on dirt. The only springs I have seen are kings, are there any coil-overs or are they all super stiff street setups? But I do live in Minnesota so coil-overs probably aren't the best option. Would AGX's be ok for struts? but Idk what springs I would pair them with.

jamal
04-14-2010, 05:02 AM
The same pricipals still apply, there's just less lateral force. You, you absolutely need camber for rally, you just don't need as much as you do for road stuff. With rally you're using the full travel of the suspension, so it's even more important to keep the camber in the good part of the curve, and that means you need to start with some.

-1.5 to -2 degrees is good on the dirt for the front, and then start at -1 or so in the rear and adjust to taste.

SFKGT is right in that the springs found on rally cars are generally stiffer than what's on a road car. My sti suspension worked really well at rallyx.

ScaryFatKidGT
04-17-2010, 12:21 AM
Thats what I'm asking, what springs/struts can I get that will bolt up to a BD that will be STi stiff or almost as stiff but maintain close to stock ride height? I would prefer some adjustability but its not required, or would it be easier to convert to a WRX suspension?

Robbks
04-21-2010, 02:10 AM
Thats what I'm asking, what springs/struts can I get that will bolt up to a BD that will be STi stiff or almost as stiff but maintain close to stock ride height?

you just answered your question there ^^
04 WRX STi springs and shocks. and different wheel alignments
it'll lower you about 5/8" from standard.
you could counter-act that for rally-x with some spacers between the strut and body

i believe the STi RA-R had adjustable shocks as standard....
but unsure if they went up to 04...?

EDIT:
here ya go...
http://www.japanparts.com/db/parts_deta ... ARCH_page= (http://www.japanparts.com/db/parts_detail.php?submit.x=34&submit.y=3&NUMBER=00025967&VOLUME=1007G-036-04S&DEALER=1&CAR=3&MIDDLE=3&SMALL=9&MAKER=4&VOLKEY=&SEARCH_DEALER=1&SEARCH_CAR=3&SEARCH_MIDDLE=3&SEARCH_SMALL=9&SEARCH_MAKER=4&SEARCH_VOLKEY=&SEARCH_page=)

ScaryFatKidGT
04-26-2010, 02:54 AM
So the best option would be an STi suspension set-up? I was wondering if there was a set-up similar that would be BD bolt on but if not thats ok. Swapping in impreza stuff isn't that hard and will open my options for strings.

Are those bran-new? $2200!??? I could get new STi top-hats and KYB AGX's with custom made springs for that price, can't I just get some used usdm STi struts and springs? or maybe GR2's for an STi with some rally/stiffer springs. Are 04's the only year that will work to swap or will any 04-07's work?

Robbks
04-27-2010, 12:29 AM
02-04STi are the way to go (04 being the best of the lot, designed for a heavier car, suits the heavier leggy much better)
05+ STi have different hub bolt spacing and needs modifications. not worth the trouble

ScaryFatKidGT
04-28-2010, 12:36 AM
So on the hunt for 04's it is

Ok um another thing on the high way today I sum how managed to fold my tire over yeah idk I took it to discount tire cuz I though I de-beaded it and lost air pressure or something but they said it was fine but I managed to just fold over a properly inflated 34psi tire???? I wasn't even turning that fast just turning on to an exit ramp Iv taken similar corners 20mph faster. They checked my tires I was at 34(the one I folded)-35 front and 32-34 rear. And It was the inside tire that folded not the outside so more camber wouldn't of helped...

So I'm thinking Group-N top-hats, 04 Sti Struts (new used idk) with slightly taller/stiffer rally springs should get me close to BD stock ride hight. Would I be able to run wider tires with this set up 225-235s?

Robbks
05-04-2010, 01:56 AM
So I'm thinking Group-N top-hats, 04 Sti Struts (new used idk) with slightly taller/stiffer rally springs should get me close to BD stock ride hight. Would I be able to run wider tires with this set up 225-235s?

I have 215/45 17's with +55 offset rims (closer to the strut) on my car and there is HEAPS of room to run wider rubber. (04 STi Struts)
i'd probably go for 235/40's for my next set, however i would test-fit, first before laying down good $$$ on new tyres that may scrub

ScaryFatKidGT
05-04-2010, 10:17 PM
I was going to go with 215/45/17s with like a +50 offset

Robbks
05-04-2010, 10:29 PM
easily fit them in there mate
+50 is even further away from the struts so 225's would again easliy fit if you want the extra width