Turbo needs replacement.
Current setup:
1998 Audi A4 1.8T Quattro, dark blue, Carbonio CAI, APR Inlet Tubes,Turbo+Intake, TAP 50 HP Chip 2, 12.5 psi, Straight Pipe, Milltek CB Exh, 17" OZ F1 225/45-17, Power Slot Rotors, Hawk Pads, South BendOFE Stage3

Aside from OEM K03 replacement, we consider:
1) T3T4 50 trim, .48
2) ditto ball bearing
3) T3s60
4) Elim GTRS (elim of GT28RS)

Our upgrade goal over current status is increased mid range torque and overall increased power. With this in mind, I would like your opinions on options 1-4. Peak power increase, torque increase @ RPM, etc. Prices/sources.



Also:

- Should the fuel injectors be changed with any of the options?
- What tuning should be done with the options (or even with a K03 to take the modifications into account; I have no idea what the TAP chip does).
- What tuning are you guys doing? How is it done (send in the ECU for example?)?
- Tuning sources, prices, etc.