11mm oil pump or an STI AVCS pump, Killer B pickup and windage tray . Upgrade intercooler to GD STI, VF34 p18 ,1200cc injectors and E85 .On a V5 STI 207 unopened is good for 300hp ATW . The 2 door in my build thread that was done for a mate was tuned by Ant Scalli and runs Haltech . With those mods made low 300 hp ATW with good AFR and EGT which the haltech runs individual cylinder EGT probes .


To go anything over this you need to look at Head studs at a minimum , bigger turbo and intercooler as intake temps start to get unmanageable. If I were going to go further id also phase drill the crank and look at forged pistons and rods . Being an open deck to keep reliability I think high 300 to low 400hp max. So going the full deal dont waste your time and put the motor together in at least semi closed deck cases.