WRX STI GC8 diff?

[Dulagarl]

need some assistance here.

I have aseen a WRX STI diff advertised on Ebay, pretty cheap at the moment. (please don't bid against me).

Am I right in thinking that:

GC8 = 1st gen wrx?
4.11 diff ratio and 4.44 diff ratio can be changed by changing the one of the cogs?


Also, I did see a 'transmission finder" chart on one of the forums in the last couple of weeks. Was very detailed about what transmission and diff went into which car. Has anyone else seen that? Does anyone have a link to it?

Before I ring the seller, I need to develop a list of questions aimed at:

1. identifying what kind of LSD it is
2. Confirming the ratio ( I know you can turn the thing and count revs, but I don't really want to rely on the seller to do that)

I also have to check my drive shafts to see if they are "innies" or "outies".

Any info?

 

[Dulagarl]

Oh: Just found the link I wanted...

https://forums.jdmvip.com/GC8_WRXSTi_transmission_compatibility_thread_Subaru_Impreza-873-t

Still have to answer the questions though...

 

[d_generate]

You can change the crown wheel and pinion in any rear diff to make it what you want, we changed the ones in my car which had a 3.9 box and a 4.1 rear diff to both being 4.44, unless it's from an RA it'll more than likely just be a viscous diff the same as any WRX would have. If you had the original box code or even year you could probably work out which ratio it is, pre 97 STI is 4.1 & post is 4.44.
The SPDA - Transmission Chart

You could take the crown wheel & pinion out of your diff & swap them over so it matches your box again, only a 30 min job for someone who knows what they are doing, just the axles you need to worry about ......I'm pretty sure open, viscous, plated or mechanical will all use the same type of CW & P, just different ratio's.