Fine Stage One stuff !
-Cold intake manifolds or upgraded one's
-Headers (All exhaust including the backcat)
Waise backcat may also be included in stage 2
-Performence plugs
-Piping
-Wiring
-Even suspension and body kits are included
-Port and Polishing that makes the volumetric efficiency better, Milling, Head gaskt replacement
And Blah Blah Blah
Stage 2:
Crower Stage 2 Camshaft and Valvetrain
AEM TruTime Camgear
High compression pistons (11.0 atleast)
Chipped ECU
A stage 2 clutch for good launches. ACT recommended
Aftermarket intake manifold and 60mm or 62mm throttle body.
MSD ignition coil, good plugs, good wires
Stage 3:
-Performence Cranck Shaft
-Performence Cam Shafts
-Changing Cam profile
-Even head swapping
-Turbo Charging/ SC
-Intercooler
-Upgradation of ECU Chip
Stage 4:
Very very serious :
Tuning gear boxes, having short shifts, upgrading valvetrains
Sequential Turbos
Forged Pistons
Installation of Stage 4 Clutch parts
DOHC Setups
Installing new valves
The deadly NOS
Making non-Vtecs actually DOHC Vtecs yes
SOme of the modifications can be changed like you can immediately switch to NOS at stage 1..