Hi guys, I'm rebuilding an ej255 aiming for around 450bhp with forged internals etc... I've seen its recommended to swap to the more durable sti 6-speed transmission if doing this. Do people usually swap to the r180 rear diff as well and if so are there any good conversion rear axles that you can source in the uk so I dont need to change hubs and everything. Appreciate any guidance as this is my first time doing anything like this, thanks.

(07 wrx hawkeye saloon 5mt)

Should be fun, make sure you get proper supporting mods or it wont last long (oil cooler, front mount etc etc etc), also worth having the block closed decked for longevity.

Have a look here, https://uk.subaruownersclub.com/forums/topic/22371-2007-sti-limited/ mines a forged closed deck 2.5.

As far as drive train, I've not had a new age wrx to sti swap, but I did have my old type R converted from a 5 speed to a 6 speed, im not 100% sure its the same unfortunately, but was a bit of a pain as its not as simple as just swapping the diff, drive shafts are different (male/female) , propshaft is a different length, need to double check ratios match. By the time you've done all the drive shafts etc may as well just get a full setup (don't forget bolt pattern may be different)

Other thing is i would very very strongly advise you upgrade the brakes before you even think about cranking up the power (if you haven't already of course), the standard 4 pots are just not up to running that sort of level of power. I had a 400bhp hawk wrx on the standard 4 pots and they were, um yeah sketchy haha

34 minutes ago, Tidgy said:

Should be fun, make sure you get proper supporting mods or it wont last long (oil cooler, front mount etc etc etc), also worth having the block closed decked for longevity.

Have a look here, https://uk.subaruownersclub.com/forums/topic/22371-2007-sti-limited/ mines a forged closed deck 2.5.

As far as drive train, I've not had a new age wrx to sti swap, but I did have my old type R converted from a 5 speed to a 6 speed, im not 100% sure its the same unfortunately, but was a bit of a pain as its not as simple as just swapping the diff, drive shafts are different (male/female) , propshaft is a different length, need to double check ratios match. By the time you've done all the drive shafts etc may as well just get a full setup (don't forget bolt pattern may be different)

Other thing is i would very very strongly advise you upgrade the brakes before you even think about cranking up the power (if you haven't already of course), the standard 4 pots are just not up to running that sort of level of power. I had a 400bhp hawk wrx on the standard 4 pots and they were, um yeah sketchy haha

Aye thanks for the response, yeah i was trying to avoid changing all hubs and everything but might have to consider it if i can find a set. And yeah I was gonna look into getting closed deck conversion. I have got slightly improved brakes but yeah you got any recommendations for these? Thanks