sounds like you want the GTX 3076r.
the tuner is wrong IMO, the gt3076r is a fun turbo to drive with....but then again Ive got cams so they would help bring the turbo on a bit
around 1800-2200 rpm you're off boost and cruising economically, 2800rpm the turbo would be at 5psi, 3500rpm around 12psi, 3800rpm its near 15psi, 4000rpm at 16psi my max setting in my profec B spec-ii EBC all the way for as long as you keep the right foot pressed down.
Im only using S15 450cc injectors, a toshi remap (for stock injectors) and an AEM fic-8 piggyback (like emanage ultimate) for a max of 240awkw/250rwkw at 1.1bar
with larger injectors, say 600cc, I could retune for near same economy but gain 10% more power. with the auto and awd Id say this turbo is maxed at around 270awkw at 19-21psi. with manual and rwd 300rwkw could be seen for sure.
Exhaust housing options would make a difference with 'lag'. A .63AR would have no lag but would max at 250kw, my .73ar exh.housing would be good for 270kw, a .86ar housing good for near 290kw, and the 1.06 would be laggy but reach past 300kw. Im using the AVO 'skyline' 6-bolt housing for a true bolton option although I understand now there are other options if you're willing to modify how your dump-pipe bolts up. ie 4-bolt housings, clamps, etc.