WRX Wagon Aluminum control arm install

[Big Sky WRX]

only 184

[penderperson]

What are the camber/caster changes from this control arm??

Are you still in STX? So then, how do you deal with 14.I.2, control arm or camber bolt, camber plate, bushings.?

Any better choices for sedans?

[Big Sky WRX]

no camber change, no caster change- they are the exact same track as the oe arms

I'm back to steel arms as you have to make a choice when swapping arms- arms or camber plates- I chose plates

However- here's an option for the wagon that I didn't try (and wish maybe that I did)- use 04-06 USDM arms (these are spec C arms)- this widens the front track (this on it's own helps dial out some understeer), this adds almost 1.5 degres of positive caster, this adds just under a degree of static neg camber- netting you -2.0 ish w/ nothing other than the oe eccentric bolt, a slight drop in unsprung weight ~ 1 to 1.5 lbs/side

In addition, the rule set allows for the slotting of struts (regardless of camber plates or arms)- this would allow almost any amount of neg camber you would want

[penderperson]

Keep in mind i'm a sedan guy. So you say slotting the original strut mount is an option. From my interpretation, 14.8.I.2 says control arms or B, C or G(plates, bolts, bushings).

Slotting of mounting holes appears to be allowed for plates and unless there's a tech bull or ruling otherwise, I'd say they're only allowed for plates. Just mounting shocks, it says the orig mounting holes may not be altered. That's what i read.

Is the weight savings/rigidity worth it to pursue control arm options? I'd like to end up with 6-7 degrees caster and 3 degrees camber, with minimal if any adjustability. Custom control arm option??

[Big Sky WRX]

it's slotting of the struts that is allowed- this came up as some aftermarket struts (zzyzx for one) optimized the mounting holes for maximum camber gain (much like a sedan using a wagon struts- the mounting holes are different thus resulting in more neg camber- a little trick many sedan guys don't know )- end result the holes on the strut can be anywhere- including being slotted.

you gain caster, lose a little unsprung weight, the arms (forged aluminum) themselves are stiffer (think big bushing and w/ slotting you can get where you want w/ neg camber

the plus side of plates is it's easy, you get almost 0 deflection out of the strut top, you increase your roll center when pushing the top of the strut in and you can cant them to get both caster and camber gains

custom arms here (sit down when you see the price )

http://www.more-japan.com/product.ph...6&cat=0&page=2

[penderperson]

WOW! $1300 Lol, it has spherical bushings though, i believe that's not ST legal.

Anything that will increase caster on a sedan with a lower price tag? Anyone ever made their own, or had a company produce them?


Ha...Just had a thought...we were talking about ALKs right. Well with a custom control arm, you could move the mounts on the arms anywhere, any angle, any offset you want. So you could optimize lift/dive and greatly improve caster/camber.

[Big Sky WRX]

you can spend even more if a guy wants

[penderperson]

That reminds me...What calipers and rotors do you use?

[Big Sky WRX]

Suby 4/2 pots- DBA 2 piece rotors front/DBA one piece rear- I've been very pleased w/ this setup- was sad to see SOA cheap out and only offer them two years (06/07)

[blazer]

OK, let me start off by saying that I am a total newb (besides my uppipe and turbo back straight pipe install that I stumbled through about 18 months ago) and have an alternate car to get me to and from work... This aluminum control arm mod took me over 1 year! I totally bit off more than I could chew with this one

What happened was I rounded the impossible to remove left front bushing nut about 15 months ago after I had taken off the sub frame and then basically procrastinated until yesterday. Out of curiosity, can you drive with out the subframe? What are the differences?

Anyway, over the last year I would periodically go down to the garage and give the rounded nut a PB Blaster spray and give the nut a try with a bolt extractor on my breaker bar but I just didnt have enough room under the car and the PB Blaster was not helping. Yesterday I finally got my baby off the ramps I had started this mod with and onto 4 jack stands about 16 inches off the garage floor. With all the extra room I was able to break the front bushing bolt loose with my foot on the breaker (which I was reluctant to do since the car was up on stands, but it felt solid). Anyway, I am just so happy that I have my scoobs back from the dead.

Thanks to Big Sky for giving me the chance to get myself into trouble, and get myself out! BTW, I did the whiteline ALK and swapped my sway bar and end links while I was at it. Time to get re introduced with my scooby.

[Big Sky WRX]

well welcome aboard! thanks..... I think

yes you can drive w/o the subframe if need be

[sxotty]

So you put these aluminum arms on then took them off b/c you could not adjust camber anymore?

It seems that this mod on the wagon might not be the best idea really unless someone designs arms that are the correct length. I thought that the aluminum arms might be nice on my wagon, but after seeing this I think I would be better off not fiddling with it

[Big Sky WRX]

no I took these arms off as they were not "legal" in the autox class I compete in- otherwise they would still be on

these (the GC aluminum arms) are the correct length- same as the wagon arms- so the geometry stays the same

a good mod (unless your competing in motorsports where it's not allowed) for wagon owners

many wagon owners are skipping the GC aluminum arms and instead going w/ sedan aluminum arms which are longer- this gives you more neg camber (in addition to the loss of unsprung weight and a stiffer arm)

[sxotty]

Thanks for the reply. So the wagon arms are shorter, more flexible and heavier in comparison to the sedan arms you are saying then? Are they made from a different alloy or something?

I actually don't have the best reasons anyway. I like to keep on top of this kind of stuff so when I replace parts I know what options I have. As I moved north where they salt the crap out of roads and watched the underbody parts deteriorate more in one winter than the previous together I began thinking that aluminum components might be nice

[Big Sky WRX]

the "wagon" aluminum arms are actually GC (older Impreza) arms- they are the same width as the wagon's oe steel arms- so the geometry remains the same- they are lighter than steel arms and much stiffer

the sedan aluminum arms are the same material- forged aluminum, slightly heavier than the "wagon" aluminum arms (but still lighter than both oe wagon and sedan steel arms), stiffness being the same

the advantages of the sedan aluminum arms are they tend to be cheaper (all the GC aluminum arms come from Japan so are rarer), they also give a wagon a slighter wider front track which adds potential neg camber

in addition, there is the spec C aluminum arm- again forged aluminum like the others, the difference being these arms add additional positive caster- the 04-06 (not the 07) USDM STi's got the spec C arms- these are more expensive than the "regular" sedan aluminum arms

so basically three aluminum arms available for the Impreza