Upgraded CT26, 550cc injectors, some type of AF management(SAFC), turbo-back exhaust, intake, Walbro fuel pump, FPR, Lexus AFM or MAFT Pro(if MAFT Pro then no SAFC), WB 02 sensor, MHG, ARP studs, Boost controller...
350hp is kinda of that HP that is in between "stages". You will need all that...