R180 & R160 rear diffs
 

if you have a wrx 2005 what rear diff does it come with a standard?? And my obvious follow up question, if you was going to upgrade to say the sti diff is that a R180 DIFF OR R160 OR SOMETHING ELSE?????:thumb::thumb:
Any help would be greatly appreciated:D

Sorry if that sounds confusing! I just wanted to know what rear diff comes on a 2005 wrx (STANDARD) and what comes on a STI???:thumb::thumb:

wrx = r160
sti = r180

Thats a great help mate, so if i bought a STI R180 rear diff would that be a dccd diff (you know the controlable one with the button by the handbrake??) Also is it a direct swap with the wrx one, or do i need new drive shafts too????:thumb:

The rear diff does not house the dccd, that is the centre diff housed at the back of the gearbox that allows you to adjust the power split. If you change to an R180 rear diff you will need the diff, shafts, hubs and read discs, lastly you would need a gearbox to match the diff ratio.

if you need a rear diff i know some one who has a r160 diff from a 2004 wrx think it will be the same ratio i think if you want i can check its done 60000 miles

Banny thtas brilliant advice!! So is htere much diffrence from a r160 diff to a r180 rear diff???:thumb:

No need for an R180 unless you are going north of 600bhp, I am running a plated R160 at 523 bhp no problems.

Banny

banny thanks for being so helpful!

So my wrx will have a r160 rear diff on my 5 speed gearbox, and that will be fine for 400bhp then? Also what do you mean plated?

Yes you will have an R160 on your car and will defo be fine for 400bhp. A plated diff has a clutch pack in it, it's also ramped, so the friction when the 2 sides are spinning different will further load up the diff. Different ramp angles and preloading can set the diff to behave differently.

Viscous Diff (this is what your car will have as standard) is hydraulic based, but uses a thixotropic gel that resists sheer, loads up based on speed.