Do STI aluminum control arms fit?

[GodSquadMandrake]

Product in question:
https://www.subarugenuineparts.com/prod ... ts_id=1194

From what I read on Nasioc, 04-06 (not 07) STI aluminum control arms are the same as Spec-C and they give you more positive caster vs the standard WRX aluminum control arms.

I want to switch to the aluminum control arms anyway so the added camber would be appreciated.

Does anybody know if these fit or how to make them fit?

[555BCTurbo]

The last thing you want on a Subaru is more positive camber

[SLODRIVE]

I think STi control arms give more caster than standard WRX arms, not more camber.

[PhyrraM]

STI arms are wider. They also have a different bushing.

You can use WRX sedan/STI struts and axles to match the width. Not sure about the bushings, STI/WRX crossmember?

[Legacy777]

They're not a direct swap if that's what you were looking for...

[GodSquadMandrake]

Excuse me, got my terms confused there. Corrected: caster.

Ok so obviously axles, umm what about tie rods and ball joints?

There were several threads about it on Nasioc and they mentioned that the bushing is wider by about 3mm and it can just be trimmed for use on the Legacy turbo subframe. Or you could just swap the subframe.

But nobodies actually done it? Why not I wonder? If you do a 6MT swap at the same time it'll save you the hassle of having to make a hybrid axle with different drive flanges on each end. Plus it reduces understeer and makes room for more adjustment on your camber plates since you won't need to adjust caster as much. And so many people have already done the aluminum control arm swap, why not put on better aluminum control arms that cost just the same?

[dscoobydoo]

Actually, the GC aluminum arms are a direct swap.

[Legacy777]

Actually, the GC aluminum arms are a direct swap.

Yeah they are, just not the STi or WRX aluminum arms. They're also a lot more expensive too.

[PhyrraM]

Actually, the GC aluminum arms are a direct swap.

And they don't have the castor improvements.

[Skruyd]

But nobodies actually done it? Why not I wonder?

I didn't have 4 grand on me at the time. It sucked

[GodSquadMandrake]

But nobodies actually done it? Why not I wonder?

I didn't have 4 grand on me at the time. It sucked

Hey dude I'm not rich either, that's why I look for OEM upgrades that you can just take off the shelf of used parts on put on your car. Like did you know that a Subaru Trebeca or however you spell it has a FSB that is a direct bolt on? Yep I got mine and it has massive girth, probably way too big lol. I think it was like $88 and I didn't have to pay shipping which would've killed me in Alaska.

Check out the link though, it's all the parts for the control arms minus like axles and it's WAY less than the GC aluminum control arms. They are over $1,000 and these are less than $300 per side.
https://www.subarugenuineparts.com/prod ... ts_id=1194

That's brand new too. You could find it used for cheaper of course.

[Skruyd]

But nobodies actually done it? Why not I wonder?

I didn't have 4 grand on me at the time. It sucked

Hey dude I'm not rich either, that's why I look for OEM upgrades that you can just take off the shelf of used parts on put on your car. Like did you know that a Subaru Trebeca or however you spell it has a FSB that is a direct bolt on? Yep I got mine and it has massive girth, probably way too big lol. I think it was like $88 and I didn't have to pay shipping which would've killed me in Alaska.

Check out the link though, it's all the parts for the control arms minus like axles and it's WAY less than the GC aluminum control arms. They are over $1,000 and these are less than $300 per side.
https://www.subarugenuineparts.com/prod ... ts_id=1194

That's brand new too. You could find it used for cheaper of course.

I was just saying because if I had the money I could have bought the whole car back. I had an 04 STI that I wanted to swap the drivetrain from, but didn't have the money at the time to buy it back from the insurance company. The only thing I would have needed was a rear left control arm and strut. That was all that broke when it rolled.

Also, I don't think you want to much caster anyways. It will put the struts in an awkward position to where they might bind. The wheel might turn like a motorcycle front wheel XD But then again, don't think it might be that drastic of a change?

[GodSquadMandrake]

Caster has an interestingly helpful effect on handling that is often overlooked. It's hard to explain and I'm not nearly technical enough, maybe some suspension guru can step in here?

It is helpful but the more caster you have, the more kickback and feedback you get through the steering wheel. It tries to center itself more forcefully so if you add caster you want power steering. Too much caster and it makes it more difficult to control the car. These control arms only add like 2 degrees so it's definitley not bad. It's just what the STI had from the factory. Again maybe someone more technical should step in and explain it (hint hint!).

[PhyrraM]

Have you considered a Whiteline ALK? It adds castor in addition to it's other more commonly discussed qualities. You wouldn't have to mess around with bushings, crossmembers and axles to do it "properly" either.

[evolutionmovement]

I paid around $500 for my GC8 alloy arms with balljoints. I need to figure out the antiroll bar mounting, now, but it's otherwise a bolt on. Kind of pointless, though, as the weight savings is pretty minimal. They seem strong as a mofo, but that's mostly unnecessary.

Too much caster makes the steering twitchy, the car is nervous and wanders. Also has an annoying feel when turning the wheel a large amount of lock at parking speeds as the car seems to lift on one side. I personally like the caster as is, but that's a personal preference. I like to be able to jump to uneven surfaces side to side with much chassis upset and increased caster makes it worse.

[Legacy777]

The main benefit from increased caster is increased dynamic negative camber when the wheel is turned. This favorable and improves handling.

This page has some good info on it.
http://www.ozebiz.com.au/racetech/theory/align.html

[GodSquadMandrake]

But only to a certain point right? Good reason to have camber plates that can adjust caster too.


This guy...
http://forums.nasioc.com/forums/showthr ... ?t=1119032

...put the STI control arms on his L, which is a GC. If GC control arms fit a BC then the STI ones should too. I asked him and he said he knows someone who has done it.
The STI bushing is 61mm and the GC one is 58. So you can just use the 58mm bushing on the STI control arm or trim the STI control arm bushing.
He used the stock end links, they have enough room for adjustment. He says the axles should be fine too, but for rally purposes with lots of droop it might be an issue.
He didn't say anything about ball joints though.

I WISH I had a suspension setup as sweet as that guy has.

[fatgc8]

Ok so what do you specifically need to make 04-06 sti control arms fit? I know they will fit but im trying to figure out if the bushings will also.What im trying to get answered is if i were to put these on my bc with the stock alk and ball joints that come with the lca would they bolt up to our cars?

[fatgc8]

Can anyone confirm?

[Legacy777]

They've got a wider track than the Legacy control arms, and I believe the bushing length is different than what fits in our crossmembers. I have heard of people using washers to shim the bushing issue. I can't speak directly on this as I haven't done it.

[Aerotech]

They will fit with a minor amount of work.
The big bushings are a bit too wide for the BC/BF mounts, but this is easily taken care of with a grinder.
The swaybar mount points are wider apart than the originals, if you retain your stock swaybar you may need different endlinks. Everything else bolts right up, and you get new ball joints in the deal. Not much weight savings, as noted above, but nuke-proof strong.

[evolutionmovement]

So those are the STI ones? What I bought was supposedly GC8, but I had to cut down the bushings and I need to get new endlinks for the antiroll bar to fit. They are, however, the same width as the stock steel ones as I lined them up and measured them as I had my suspicions that they may not have been GC8 as advertised.

[Legacy777]

If you got GC specific aluminum arms, they're supposed to be a direct fit. But they're expensive as hell!

[evolutionmovement]

Yeah, I remember seeing them for a grand or more when I bought mine for what I thought was a great deal, but which I find out now was probably just average at the time. Oh well, they look cool covered in cobwebs underneath the unmoving wagon.

[legacymax]

I believe it is only the 04 STi controls that will fit. In 05 I thought they changed the control arms along with the steering rack and cross member. Can anyone clarify?
-Max