[kingbrew]

Hey guys, just looking for some input here on my planned suspension setup. I've been doing a ton of research and I think I've got it narrowed down. A little background first-- 05 STi, that's my daily driver and will be autocrossed about twice a month in STU, and probably some Solo one races in the future. Right now it is fairly stock, except for exhaust and a cusco roll cage.

Here's what I plan to add:
Whiteline adjustable FSB 27mm
Whiteline adjustable RSB 24mm
Whiteline front and rear end links
RCE yellow springs
Front strut bar

I really don't mind a stiff ride for the road, and the roads are pretty good where I live--pretty much no wheel bending pot holes etc... Also, I just got the rear struts replaced under warranty, so I'm going to wait a couple years or so til they die again, then put coilovers in.

Any and all feedback would be greatly appreciated, especially from fellow autocrossers running a similar setup. Thanks guys!

-Ryan

[stretch]

Skip the springs and get camber plates with the money. Springs have a very small effect on times, but alignment can make a huge difference. Besides, without sufficient camber up front you'll get nothing but terrible understeer with that sway bar combination. I prefer more equally sized bars but opinions on that seem to vary greatly with driving style.

You may already know this, but the hierarchy of ways to decrease lap times goes something like this:

1) Improve the driver
2) Improve the tires
3) Improve the alignment
4) Improve the suspension
4a) Sway bars (according to driver preference)
4b) Dampers (though this is usually most important for other cars)
4c) Everything Else
5) Improve the motor

[kingbrew]

Originally Posted by stretch

Skip the springs and get camber plates with the money. Springs have a very small effect on times, but alignment can make a huge difference. Besides, without sufficient camber up front you'll get nothing but terrible understeer with that sway bar combination. I prefer more equally sized bars but opinions on that seem to vary greatly with driving style.

You may already know this, but the hierarchy of ways to decrease lap times goes something like this:

1) Improve the driver
2) Improve the tires
3) Improve the alignment
4) Improve the suspension
4a) Sway bars (according to driver preference)
4b) Dampers (though this is usually most important for other cars)
4c) Everything Else
5) Improve the motor

Good thinking! I almost forgot about camber... I'll put that on the list as well. What would you recommend, whiteline camber plates are a littel pricy but seem like they'd be best.

[XDNBC]

I agree with Stretch's priorities and would add- skip the strut bar too.
I run in STU on the stock RE070 tires and springs. I have WL 27FSB and 24RSB and PDE camber plates [these raised the front about 10mm] with alignment set to -2.35F and -1.57R with 0 toe-in. I currently find that cold 38psi front and 35psi rear work best for me. I am aware that different driving styles need different antisway bars, alignment and tire pressures- you will have to find your own balance. The setup I have gives me a smooth transition into trail brake or power off oversteer that I can maintain when I add throttle [is that still a correct term?] accellerating out of a sweeper. It also gives me a bit of understeer when slaloming- which I like- when I lowered the rear pressure to 33psi I got too much penulum effect. When my tires wear out [and they have 6/32 left after 8 AutoX and 4 HPDE track days] I will probably get 245/40-17 tires-either Bridgestone 01Rs or Yok AD06s.
I would still a bit more grip but have done well this year.

[Vikingmoose]

Is a rollcage even legal for STU? Also, you didn't specify what kind of exhaust you have, but if it's catless, that puts you into BSP. Also if you have a Cobb AP, that also puts you in BSP. Now on to my recommendations:

Tires are the most important thing. If you're still on stock RE070s that's ok, they are good. When those are done, or if you feel like moving on, the Bridgestones or Yokohamas are THE tires. In fact, most of the top drivers at the National Championship are on Yokos. Camber plates, yes. At least -2.5 up front, more if you want it or feel comfortable with it.

Since it seems you will be skipping coilovers at least initially, you may want to consider adjustable struts to compliment whatever springs you use. Adjustable struts are a great way to improve transitional handling while maintaining daily driver comfort (struts dependent).

It's getting late, and I'm tired so I might have forgetten or skipped something. Good luck with STU!

Justin

[kingbrew]

Originally Posted by Vikingmoose

Is a rollcage even legal for STU? Also, you didn't specify what kind of exhaust you have, but if it's catless, that puts you into BSP. Also if you have a Cobb AP, that also puts you in BSP. Now on to my recommendations:

Tires are the most important thing. If you're still on stock RE070s that's ok, they are good. When those are done, or if you feel like moving on, the Bridgestones or Yokohamas are THE tires. In fact, most of the top drivers at the National Championship are on Yokos. Camber plates, yes. At least -2.5 up front, more if you want it or feel comfortable with it.

Since it seems you will be skipping coilovers at least initially, you may want to consider adjustable struts to compliment whatever springs you use. Adjustable struts are a great way to improve transitional handling while maintaining daily driver comfort (struts dependent).

It's getting late, and I'm tired so I might have forgetten or skipped something. Good luck with STU!

Justin

Hey Justin.

First, a roll cage is legal in ANY class. The exhaust I have is a Blitz Nur Spec R catback. And I don't have a chip or Cobb AP. I still have the RE070s on. They seem to work pretty well, but when they are done I will upgrade. As for adjustable struts, I didn't know anyone made struts for the 05 STi, can you suggest a specific adjustable strut??

Once again, thanks for the help.

[Naruto]

forget the front strut bar, it doesn't do much but look pretty. Also I confirm stretch's opinion on the sway bars without more neg. camber (not that I have to confirm, is that guy ever wrong when it comes to suspension?) I'm running the exact sway bar setup you're looking at except kartboys in the rear and I've been having a lot of understeer problems at the autoxes. Just got plates in and will be installing them this week for next weeks autox so hopefully that will help. Oh and dont forget new mounting brackets for the rear, I hear some people had some problems.

edit:

Originally Posted by Turninconcepts.com

Nope - I've only heard of one case of the stock mounts breaking with that bar. The warning is a holdover from the old bug-eye setups that had weaker mounts. Subaru started using beefier ones in 04.


<- long time 24mm rear bar user

My friend really recommended doing parts a little at a time so you can actually feel what is doing what when you autox, if you put in everything at once and theres something you dont like it'll be more difficult (and more expensive) to figure out what it is so you can change it. That being said, having done the front sway, autoxed, then put in the rear sway and autoxed... you should do those together and avoid what I went through (i.e. ok here comes the turn. brake. turn wheel. accelerate. car keeps going straight. punt cones into atmosphere)

[BigSky]

Ohlins makes a fixed perch adj strut- guys have now figured out how to get Koni inserts in the oe STi housings as well

[kingbrew]

Originally Posted by BigSky

Ohlins makes a fixed perch adj strut- guys have now figured out how to get Koni inserts in the oe STi housings as well

Ya the Ohlins are BIG $ though... And never new guys were putting the Koni inserts in 05 STi's I thought it was just the 04s.

[BigSky]

better get to reading - the inserts are going in 05+ oe struts

[Dark_Helmet]

Well just like everyone else said, you need camber plates. I've got camber bolts in mine that are only going to have to last me 2 more events and I've managed to get them to -2.3 on each side. I had alot of problems with the bolts slipping until this last time I got them torqued down to about 150 lbs and they don't slip anymore. But if you don't get some more negative camber in the front you will absolutely cook the outside edge of your tires. At least I did.

[SmoothSTi]

Dyno tunes on a Cobb Accessport for STU/STX shouldn't keep you out of STU guys. No changes to BOOST, but you sure can change a whole lot of other stuff GET ONE! lol or just buy one from PDX