1. i know thier is a pop charger (not sure what that is if want to explain tell me) by JWT
2. an injen intake system(if i get a 300zx i want this if anything wrong with this system please inform me).
3. Exausht (can u tell me the name brands and models and prices(all the price i seen was 900 dollars and higher ahhhh!!!)
4. stillen headers
5. ??? please tell me more

this is what most people follow when they upgrade a N/A Z

JWT POP charger & Underdrive pulley will get you 238 hp
JWT ECU Upgrade will get 250 hp
Performance cat-back exhaust system (also ALC for A-T)-262 hp
Stillen headers-279 hp
Ported throttle bodies & Matched intake-290 hp
Injector upgrade & JWT NOS system-390 hp
SGP head package (porting & 5 angle valve job)-420-430 hp

a pop charger is an intake and i don't know what exhaust you should get i would say whatever you can get a good deal on or if you want a name brand....