If you were "piecing" your suspension together without donor....(818R)

[C.Plavan]

Subu Gurus- Would you go for all 2006 Wrx suspension (hubs, knuckles, etc) or would you go with an 04 Sti (4x100) essentially the same? I'm not sure about caliper/brakes yet, may go with the Wilwood upgrade which I feel will be overkill (except for the reduction in weight).

I'm sure I'm missing something, but I'm getting ready to start ordering parts.

Which aftermarket adjustable components would/could you/I substitute? (Whiteline?)

Pros/cons- strictly for 818R.

Thanks in advance.

[Ironhydroxide]

First off. 5x100 (probably a mistype). BUT, were it me, i'd go with

08+ Front Knuckles (bolt in bearing/hub, 5x100)
06 Rear Knuckle (if i wanted stock 2pot rear, if not, any year 89-05 would work)
Aluminum front control arms, (i read somewhere at one time someone made and adjustable length one with Spherical bearings, but cant find it ATM)
Adjustable (probably perrin, etc.) rear Lateral Links,
Adjustable Trailing arms (same as above)


OR, because i'm me, and crazy.
I'd make my own bracket for the STI front knuckles 05+ and go that route. 5x114.3 the whole way. wheels are cheaper and easier to find sizes for. a myriad of brake upgrades. etc.

[PhyrraM]

Front knuckles/hubs:

The same from about 1998-2007 (minus '05+STI). If you don't need WRX spec speed sensors, look among '89-'04 Legacy/Outback, '93-'07 Imprezas (except '05+STI), Bajas, '97-'08 Forester -they are all functionally the same. All can be used. They take the same balljoints and tie-rods. The hub design changed a bit to accommodate different styles of ABS sensors (or lack of ABS). All take the same CV shafts and have the same 5x100 bolt pattern. All take the same rotors and have the same caliper mounts so brake interchange is 100%. You may even find some that are lighter than others.

Rear knuckles/hubs:

All from an AWD donor should work. The same year ranges apply ('89-'04 Legacy/Outback, '93-'07 Imprezas, Bajas, '97-'08 Forester) but the details are different. There are drum brake versions that will work, but are likely not desired. Most of the disc brake rear knuckles are completely interchangable with each other including the various sizes of rear discs and calipers. The exception is the models with fixed, 2-pot rear calipers ('06,'07 WRX in North America). On those the caliper mounting bolt pattern is different. On STIs the drum-style parking brake is a larger diameter making STIs different yet. As far as geometry goes, all are the same and will bolt to the 818 just fine- only the brakes need to be figured out. There are 3rd party adapters to mount the 2 pots calipers on the much more common single piston caliper knuckles.

Front control arms:

Three basic dimensional version (not including the aluminum variants of each). All early cars had essentially the same control arm ('89-'04 Legacy/Outback, '93-'01 Impreza, 'Baja, '97-'02 Forester). It is the narrow version with a "small" front bushing. These would need a few spacers to make the front bushing "wide" on the 818. The second is the narrow control arm with a "wide" front bushing ('02-'07 Impreza wagons). The last is the wide control arm with the "wide" front bushing ('02-'07 Impreza sedan). Going off of photos, it appears that FFR is supporting both on the 818S, but only has the locating spot for the wide control arm on the 818R. Personally, I think using the shorter arms on the 818R would provide about 3/8" more room for wider tires or offset. I'm sure the upper control arm has more than enough adjustment to compensate.

Rear control arms/lateral links:

Only need to worry about wide and narrow versions. Only '02-'07 Impreza sedans have the wide links. Adjustable aftermarket parts are available and likely desirable negating the hunt for rare aluminum parts.


Aftermarket parts:

Most of the common aftermarket parts for the Subarus are for either general firming (bushing etc.) or to correct for alignment decisions Subaru made in the design phase (roll center kit, etc.). The latter are rendered useless by FRR redoing all the basic geometry. The light weight of the 818 will effectively make all the bushings fell firmer too, so those may not even need the same attention they get in a stock WRX.

[PhyrraM]

Do the '08 Knuckles have the same geometry as all the earlier ones? If so, then they could be an upgrade to 20 years of Subarus too........

[C.Plavan]

Yep- mistype 5x100

Hmmmmm 08+ front hubs. We positive they will work?

[HelluvaEngineer]

Would the front knuckles from the 05 Legacy GT work? I have an extra set of front brakes with the Knuckles. I was hoping to use them.