Ed can only get power out of your vehicle if you have the mods that let him. he or nobody can get power out if you don't have the mods.
Roughly:
Bog stock = 140160 or so they quote.
std turbo, fmic, pod, exhaust, z32 = 180- 190rwkw
above plus 555 injectors and fuel pump = 200 - 210rwkw
above plus ex cam pulley, power fc and GCG hiflow = 220 - 240rwkw
above plus cams = 250 - 270rwkw.
above plus turbo gtrs/2835proS/apexi53b70 etc = 260 - 280rwkw.
Then start looking at engine internals.
And most tuners can get these figures if you spend $$$ and supply the hardware.
Don't know if this helps or is what your looking at. Plus there are more than several ways to approach the whole performance thing, safc, haltech, other turbo's etc etc and each person has their own idea about what is the best way to do it.
All it takes is $$$$ The definition of being poor = owning a Skyline...lol.