Saturday, February 16, 2008

Gc8 aluminum Control arm install

Aluminum control arms install just like the steel oem parts, as they are OEM subaru and their only difference is Aluminum contruction instead of steel. Uses the OEM subaru identical pn ball joint with a small aluminum adapter sleeve to fit the ALU countersunk arm instead of the steel taper welded into the steel arm.

Direct bolt on, to all GC8 (if the arm is from a GC8 - GDB and others are differnt).
Many people who go aluminum arm also go with 6 gun or Zerosports style Extended Lower ball joint (to alter Mac Strut geometry to allow for lowered car)- very much like NCRCA on AE86 or spacer for short stroke conversion.

ball joint goes to knuckle, ALK goes to chassis- different point entirely, has nothing to do with each other.

the front control arms on a subaru are attached at 3 points:

17mm@ front X member (nut+bolt long)
19mmx2 @ ALK bracket position
14mm ball joint pin bolt to knuckle
14mm @ sway bar link

the removal is done as thus:

1. Jack up car, remove wheel (ideal to jack both sides and put on stands, so no compression on front sway bar)

2. Remove 14mm bolt pin that holds the ball joint to knuckle. use pickle fork or hammer + screwdriver to force balljoint out of the knuckle- gets rusty in there.

3. remove the 2 19mm bolts that hold the ALK bracket to chassis.

4. remove 17mm nut and bolt that hold control arm to front crossmember

5. Re-install.

6. Get alignement.

[QUOTE=spinninhye][QUOTE=supermoose][QUOTE=spinninhye]I could give you 300 shipped for the ra aluminum control arms. Not tryiing to lowball you but it's all I can afford. Thanks[/QUOTE]

I have an identical set (without ball joints- you can re-use your existing ball joint if good, as steel/aluminum arms use the same ball joint.)

i can do $300 shipped that pair. Direct plug and play into your car

I don't have that much knowledge on these, I have a whiteline ALK so I guess I don't really need the bushings at the end.... any way to get them with the balljoints but without the lift bushings? Where do the ball joints go exactly and how is the removal/installation done? Is it easy? Anyway let me know man.


Wednesday, February 06, 2008

ej25 dohc heads vs JDM WRX ej20K version3/4 heads

Turbo heads are differnt than NA heads in port shape, chamber shape, and valvetrain sufficiency. turbo's are obviously cammed for turbo, NA heads are cammed for NA power output.

[QUOTE=Sarra;1289638]Well, I've got DOHC 98 Legacy GT heads. I'm not sure if they're the same or not, but I've also heard that the 98 DOHC Legacy heads are very similar to JDM WRX heads as well, so they might be the same.

I'll eventually be upgrading to turbo cams and a better valvetrain setup. I just want to get this ****ing supercharger on finally![/QUOTE]

The heads are similar in original casting, un-similar in the fact that:

cams are differnt. - less aggressive - the ej20K 97/98 head which shares basic structure has ~252 deg cams in some varients.

most dohc ej25 heads found in usa pre 98 are older style rocker arm / hla dohc setups. the ej25dohc in 98 RS has the ver 3/4 ej20K wrx style valvetrain with under cam shims.

ports are completely different. there are no similarities, except for if you had a lot of time and the machine shop to do it, you could port and shape a ej25 dohc 98 rs head into a ej20K 98 sti head. I have had both engines and both heads in my hands (in my car).