im running a s2 rb25 turbo on my rb20... and set at 12psi which is good 4 a 13.2 pass on street tyres
with a intank walbro pump, fmic with custom pumpin, 3in turbo bak wit spilt dump and no cat... pod filter, bov, oil cooler kit.... still got stock ecu, injectors, coil paks
25 turbo's r got mild step up 4 $$$..... but u got urself a good platform there and hi-flowing a 25 turbo is a good idea.... but in saying that u could buy somthing slighty bigger 4 da price..!!!
anyways good luck with it!!!!