a high-flow turbo is just going to increase lag.. i would think that although you are chasing peak power, if its low-down torque you want then is this really the best option?
obviously things like lighten the car, and increase power are going to help, but if you are chasing specific things that are going to relate to low-down torque, maybe consider
- cam gears
- lightened flywheel + pulleys
- remove clutch fan and replace with thermo fan(s)
- responsive turbo
- aftermarket ECU: plenty of low-down timing and good AFRs
- if you are planning on running low boost, maybe consider stock intercooler for reduced piping? or a small FMIC rather than a huge core?
i don't know, just some ideas...
its obvious to say "just put on an exhaust and wind up the boost" but we already know that will make more power. let's help him get his low down torque.. i know personally (having an rb20) how a lack of low-down torque can kill the fun!