i have looked in2 turboing an a15 already and i was told that it could be done, but would be a lot of time and maybe money too, and injected would be tha way 2 go aswell but again more time and money bcoz tha thing u gotta rememba is that they arnt commonly turboed or injected so it means custom manifolds etc, also i was told that internals mite not be strong enuf specially if u wanna up boost.
i dunno how true all of this is, i m still considering going ahead with it all and if i do i will let u no. my advice is keep asking questions i m sure there would b sum1 in nz that could help u good luck