-GT25R
-Exhaust mani, assuming that the GT25R is not a direct bolt on which i do not beleive it is.
-HFC or TP if the GT25R will not directly bolt on to the stock one.
-Software
-Bigger Inlet hose
-Probably a VR MAF
-Injectors
-Myabe a different FPR

You could probably get away with just that aboe, but i woudlnt do it, i would also get

-Exhaust
-DV
-MBC or EBC
-Fuel filter
-Colder spark plugs
-You will need a FMIC, but not immediatley
-Clutch, same deal as the FMIC

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