Subaru WRX Build EP5: Cusco Plated LSD Install and Laps

We install a Cusco LSD in our VA Time Attack WRX to address an annoying traction issue out of slow speed corners.
I go into the detail of the install as well as whether it’s worth it and we go for a lap!
#wrx #subaru #stratifiedtuned #lsd #timeattack

[@nicsye12]

love my cusco diff in my WRX, I'd say its the most game changing mod for the car.

[@stratifiedauto]

It is definitely a great upgrade.

[@ittotaq]

Which one did you get

[@FuJiNF]

Once you get used to the handling character with that diff, you can push it harder. Late apex! Once you get the line right you can pretty much throttle before hitting the apex. So i take it you're going with the sti 6spd now since the wrx tranny died? Gonna swap to R180 too?

[@stratifiedauto]

Yes full STI swap. We may end up doing a plated R180 but first I want to see how this car is with the STI transmission. Swap should begin very shortly here.

[@FuJiNF]

@@stratifiedauto take the R180 out and rearrange the plates. Subaru sets it 75% lockup only. Run regular gear oil for good lockup. The 45° ramps on the pressure rings are meh..... even with some rear bias, it doesn't feel good like a good rear LSD. My JDM 04 6spd is the 35:65 and even that is like..... there's a little bit of rotation but a good rear LSD makes a world of a difference as you already can feel. The factory rear plated LSD can't hold much when you lift the inside rear tire if you don't have a DCCD controller. The controller will help a lot in those tighter camber corners.

[@stratifiedauto]

Thanks for the tips. Our transmission is out of a 2018 STI. I was under the impression that Subaru used a rear torsen in these years.

[@FuJiNF]

@@stratifiedauto Your welcome! Starting 07Sti, Subaru went to Torsen. 04-06 ran the plated. If you look around hard enough you should get a 06STi rear diff as that will be the 3.545FD with a plated diff if you wanted to play with the factory plates.

[@stratifiedauto]

Good to know. I was thinking going Cusco again if doing the rear end. Currently I don’t have dccd but did get the harness to plug one in. It should be stuck in rear bias.

[@martinssau]

What settings are You using for that cusco diff element?

[@stratifiedauto]

The factory settings. Have not taken it apart.

[@palaciosfreddy9189]

Single exit exhaust may help.

[@reflexboxer2ndlt807]

You can go much faster around those corners dude. You have a LSD AWD. Get some aero next

[@gerik3343]

do you know what is the torque spec for the allen bolts on the cusco differential.

[@stratifiedauto]

Do not odd hand. Had not needed to rebuild it yet.

[@amzarraihanramlan5872]

Did u do break in?

[@stratifiedauto]

Yes. It does need a bit to break in plates and need to do a first oil change earlier than next changes.

[@messi3666]

Was the lap time better with the LSD on?

[@stratifiedauto]

Yes the plated lsd made a big difference. And then our front diff blew up. Now the car is getting an STI transmission swap. Stay tuned for this.

[@messi3666]

@@stratifiedauto Thanks for replying back. Just making sure the Cusco LSD fits 2015+ wrx, right? Thanks, bro

[@555_Kochi_STi]

@@messi3666 Cusco makes plated diffs for GC chassis to VA, so yes.

[@messi3666]

@@555_Kochi_STi Thank you bro

[@PG_Narkles]

@@stratifiedauto Was the front diff's blow-uppage due to having an lsd in the rear and open diff in the front?