I am doing a bit of a hybrid setup (Also waiting for Doug, early Jan)
- R160 5x100 front end using existing shafts. R180 5x100 Rear, r180 hubs + shafts with plated spec-c diff, mine is a 3.9 though.
So i don't believe you will need to convert your hubs to 5x114.3 to upgrade to R180. Just need to get the right diff to match your 6 speed, which would be the STI 3.54 rear. Plated or not. But plated would be the go. Otherwise you get a R180 diff and swap out the centre appropriately. Cusco RS etc, but you would need to keep it 3.54 to keep your 6 speed happy.
I believe the Spec C ones are plated, all other 3.54 STI R180 vary to some degree.
Ebay has lots of R180's but they are all 3.9. Was a 3.54 on here earlier but it sold.
I was going to to a 2006 3.54 setup, but found it too hard to come by. So ended up doing a spec-c 2002 type configuration.
Try posting on FB Groups:
Subaru Car Parts Australia
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