part #'s of interest for 08/09 WRX guys

[Big Sky WRX]

Thought I'd put together a list of part #'s that may be of interest for folks looking to upgrade using factory parts

I'll preface by posting what has what and what fits what

the 2008 WRX has a 20mm front sway bar and a 15mm rear sway bar
the 2009 WRX has a 21mm front, w/ a 16mm rear
the 2008/9 STi has a 21mm front, w/ a 18mm rear

the rear STi sway bar WILL fit the WRX, the front STi way bar will NOT fit the WRX

the 09 WRX received firmer springs- to the tune of 40+% stiffer, along w/ the firmer springs- firmer valved dampers
the 09 WRX also received firmer tops front & rear- these are the same tops as the STi uses (same part #'s)
the STi utilizes springs that are the same rate as the 09 WRX, but uses different dampers- the STi front dampers will NOT fit a WRX, the rears would but no real benefit to the STi ones over the 09 WRX ones

to the part #'s

09 WRX front sway bar (21mm) 20401AG040
09 WRX front sway bar bushings (need 2) 20414AG070
08 STi rear sway bar (18mm) 20451FG010
08 STi rear sway bushings (need 2) 20464FG010
09 WRX front right strut 20310FG080
09 WRX front left strut 20310FG090
09 WRX rear shock (need 2) 20365FG060
09 WRX/STi front top 20320FG010
09 WRX/STi rear top 20370FG010
09 WRX springs front (need 2) 20330FF060
09 WRX springs rear (need 2) 20380FG090

[M2KS]

Sweet b'jesus Big Sky - nice work !!

[butlejas]

Hey I'm sure many people have seen this by now, but the spec C rear swaybar from the 2010 sti SE is a 19 mm. Should fit as well... 2010 part # 20451FG020 (and its CHEAPER than the 18mm! WTF?)

Also, since the new 2011 WRX will be given a wider track to match that of an sti... is it possible that the front dampers from an sti would fit?? I know that they couldn't before because of the narrower track... any insight would be appreciated.

[Big Sky WRX]

^ good find - the spec C bar purchased from Japan was $$$$

the front struts not fitting isn't due to track width- it's the knuckle design (superior in the STi) that prevents swapping

if the WRX in 11 somehow ends up w/ 5x114 wheels then we can assume they've switched to the same knuckle, if they remain 5x100 they've stuck w/ the same design

I do know they are upping the wheel width to 8" which will be a welcomed change

[Big Sky WRX]

here's the 19mm bushings (order two) 20464FG020

[butlejas]

hey thanks big sky! I am assuming that the difference in knuckles would apply to the rear shocks as well?

[Big Sky WRX]

there are some minor differences in the rear shocks, but I don't think they are due to the knuckle, I'm 99% sure they aren't swappable either

[fahr_side]

there are some minor differences in the rear shocks, but I don't think they are due to the knuckle, I'm 99% sure they aren't swappable either

The rear shocks are not different because of the knuckle, they bolt up to the LCA, not the knuckle. STi rear shocks seem to work fine on the WRX.

The knuckles are different between the STi and other Imprezas because of the different hubs. The bushings are identical across the range (at least until '10), as is the LCA, tie-rod, upper link and trailing arm. It's the wider rear subframe that increases the track on the STi.
It might be that the caliper mounting lugs are spaced differently too, relative to the hub mounting face, but if you were changing the hubs out you'd probably be running STi or compatible brakes back there anyway.

The '11 WRX still has 5x100 hubs btw, so no progress there, and STi front struts will still not fit the '11.

BTW, I don't think there is evidence yet to support the talk that the '11 WRX has a wider track, just that is has the wide body and wider rims. Subaru could be claiming a wide track based on the 8J vs. 7J rims and the still unknown offset. We will know soon enough!

[Big Sky WRX]

are the shock bushings the same inner diameter between STi and WRX- I thought there was something that prevented there use

I believe the control arms are different in the rear (and front) between the STi- someone posted a pic of two rear ones side by side

Whiteline makes some honky adjustable rear control arms that are STi specific- that's where it was pointed out they are different

[ScorpionWins]

This kind of answers a question I had as to whether Eibach springs for the 09 would work for an 08.

My buddy wanted to sell me his 09 eibach springs.

All Eibach would tell me is that the 09 had the same fittment but different spring rate, but would say how much different.

40% is pretty significant, and probably wouldn't do well on 08 stock struts.

Thanks for the info.

[fahr_side]

are the shock bushings the same inner diameter between STi and WRX- I thought there was something that prevented there use

I believe the control arms are different in the rear (and front) between the STi- someone posted a pic of two rear ones side by side

Whiteline makes some honky adjustable rear control arms that are STi specific- that's where it was pointed out they are different

I know the shock bushings have the same bore because the bolt part numbers are common across all the 3G Imprezas and I know of a guy here that has GRF rear shocks on his GH8.

The upper control arm has the same part number for both GR and GH. Maybe there was a running change and they used the same part number. Bad practice but it happens.
And yes, I remember WL stating their part only fits the STi. I just don't know why. :shrug:

[Big Sky WRX]

good to know on the shocks- probably better damped on the STi (oe)

here's the post I was thinking about on the rear control arms

http://forums.nasioc.com/forums/show...postcount=1592

[fahr_side]

good to know on the shocks- probably better damped on the STi (oe)

Anything is better than the junk they put on the GH WRX so far. Seriously, I have heard only good things about the GR shocks and the GRF I rode in was very well damped. I think there is some slight issue with the ride height being lower however. Given that the GR rear spring is slightly longer than the '09 WRX item, I think the GR spring perch must be lower than on the GH items. A saggy-butt spacer may correct this however.

here's the post I was thinking about on the rear control arms

http://forums.nasioc.com/forums/show...postcount=1592

Yes I remember the conversation, but Opposed Forces have the same part number for all 3G Impreza models from 2.5i to STi...

http://opposedforces.com/parts/info/20252FG000/
http://opposedforces.com/parts/info/20252FG010/

If their data is wrong I apologize for posting it and muddying the water.
I started looking into this a year ago, thinking I could get the GR's track on my GH...

[Big Sky WRX]

the one thing supporting that they may be different is the STi only listing on the WL upper arms- they usually aren't shy about listing other apps if they fit

[spt wrx 2k8]

So could I use my STi pinks for my 08 WRX w/ 09 WRX front right strut 20310FG080 - 09 WRX front left strut 20310FG090 - 09 WRX rear shock (need 2) 20365FG060?