Hey wetpatch to reset your ECU all you need to do is disconnect
from battery leave for a while and reconnect ..........now there is a
procedure for doing this correctly i think ????? but basicaly that's it.
Anyway a Classic shape impreza's ECU can only retard 1 or 2 octane
which won't be enough for our 95RON.
As Alan said Octane booster & Knocklink till ya get the re-mapp.
Niall.