I don't think so...! This is totally impossible...~~
The based Impreza cannot modify to be a STI.., but I have heard most of the WRX owners.., they can basically swap the STI turbo.., computer to the WRX...!
It will be finally succeed....
Anyway..., STIs have two different models.., they certainly come with two different engines... Do you know that...???
Japanese version = EJ20
American Version = EJ25
If you are seriously wanting to do this conversion...
Buy the STi engines from the used car engine market....
Giving up on your original one..
This is the only way to do with that...
One More important thing..
From the based Impreza to WRX.., the bolt pattern is way different than the STi..
The based impreza is 5X100 and the STi is 5X114.3
If you are seriously wanna get a bigger caliper...??
But Well..., if I were you..
I prefer to buy a STi instead of doing this conversion.., cause it's wasting time and money..., this is my personal idea...
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