welcome to another gt4 owner
don't forget to install a boost gauge
HA and dont ask danny how to do it !! ( pokes danny in a HAR HAR way )
boost guage is essential - i can give you a quick spin on how to install a Speco one as i did this a month ago and the pain and cuts on my hands are still fresh though it DOES work - and the stock ECU is good for 14psi with the other tinkering mods i have !
my gt4 runs a maximum 14psi boost and very comfortably with an aftermarket simple boost controller that i can adjust from the cabin and a little tweak to the fuel pressure fuse, and a cat back exhaust ( nothing special but sounds nice ) - otherwise she's basically stock - and is currently holding top st185 Gt4 that's listed as a toymods dyno day competitor ( UNTIL Anhar and danny get theirs on the road - BOO ! and only beaten by two ST205 WRC's on the day though dave's not that far off beating me too!) so if you want any details on how far you can go with bolt on stuff and still get good performance from it - ask away - Im in the process of getting every possible thing i can think donr to the car without having to pull apart the motor OR swap the ECU
Ill be focussining on suspension + tyres wheels in the next month - followed by exhaust and turbo rebuilds (52mm wheel on the way just need the other one! )- highflow here i come ! )
Re filter - give the pod the arse and utilise some home grown nutting skills to create cold air induction into the airbox you already have and utilise a decent panel filter - this by far would be the easiest to do + you dont get that nasty underbonnet heat issues ( ill be doing the cold air induction the first chance i get when i come home !!! theres 3+ more KW in that muahaha )
Exhaust for EVERYTHING dump pipe - piping, high flow cat ( you need one ) and mufflers - instaled - your looking at about 1600 ish dollars - this is what i was recently quotedas an estimate of the 3 inch straight thru system i want ..
The suspension side of things - you cant beat the whiteline " handling " pack for goodness - they retail for about 1500 + installation and solve most of the Gt4's handling woes + from what ive heard REALLY makes a difference in aiding the cars handling
Brakes are pretty good off the mark - though if you want more power - a set of DBA slotteds up front and decent pads shouldnt cost more than about 500 for the lot - OR you could try adapting a set of 4 pot calipers and 205 rotors - but honestly i have no idea on the $$'s involved here
Also - GET A TURBO TIMER!!!! its a !must!must! to help prolong turbo life
Anyway
ive rambled enough - if i think of anything else - or if you have any questions - fire away - im new to this too - and the guys here who already have them are SUPER handy for info