Stage Charts - 300ZX

Stillen came up with the first stage chart, as a rough guide to how the most effective way to upgrade 300ZX's. Unfortunately, with the new mods coming onto the market, their charts are a bit outdated. So, SGP Racing, one of the best 300ZX tuners in the USA, came out with their own guide. Both are included below, for both the TT and NA versions.

Stillen Chart - 300ZX TT
Stage Modifications Required Approximate M-T HP at Flywheel & Boost Pressure
Stock None 300hp @ 9.5 psi
I Performance cat-back exhaust system 320hp @10 psi
II High flow intake 340hp @ 10.5 psi
III ECU EPROM upgrade & boost jets 396hp @ 13.5 psi
IV Larger intercoolers 405hp @ 13.5 psi
V EVC 418hp @ 14.5 psi
VI 555cc injectors & 550 type turbo upgrade 445-500hp @ 16.5 psi
VII Dual high flow intake 520hp @ 16.5 psi
VIII 600 type turbo upgrade 620hp @ variable psi
IX NOS 680-760hp @ variable psi
     
Stillen Chart - 300ZX NA
Stock None 222hp
I Performance cat-back exhaust system 234hp
II Computer Upgrade & Intake 254hp
III Nitrous Oxide & Injector Upgrade 300-320hp
     
SGP Chart - 300ZX TT
Stock None 300hp @ 9.5 psi
I JWT POP charger & Underdrive pulley 305-325 hp 10 psi
II JWT ECU upgrade & boost jets 365-380 hp 12-14 psi
III B&B test pipes & Gut pre-cats 385-400 hp 12-14 psi
IV Performance cat-back exhaust system 400-415 hp 12-14 psi
V EVC 420-435 hp 15 psi
VI JWT NOS system 490-505 hp 15 psi
VII Larger intercoolers 495-510 hp 15 psi
VIII JWT dual POP charger 510-525 hp 15 psi
IX Ported throttle bodies & Matched intake 515-530 hp 15 psi
X Nismo 555cc injectors 530-545 hp @ 17 psi
XI

Sport 500 turbos
Sport 600 turbos
Sport 650 turbos (cam upgrade required)

555-575 hp @ 17-21 psi
560-605 hp @ 17-21 psi
620-675 hp @ 17-21 psi

XII JWT cams & SGP head package 640-695 hp @17-21 psi
     
SGP Chart - 300ZX NA
Stock None 222hp
I JWT POP charger & Underdrive pulley 238 hp
II JWT ECU upgrade 250 hp
III Performance cat-back exhaust system (also ALC for A-T) 262 hp
IV Stillen headers 279 hp
V Ported throttle bodies & Matched intake 290 hp
VI Injector upgrade & JWT NOS system 390 hp
VII SGP head package (porting & 5 angle valve job) 420-430hp