IowaSilvia_S13 wrote: Don't go with the apex exhaust.. everyone has them.. go with a blitz or hks..
:slap I hope thats now how u make all your decision in life...based on what 'everyone doesnt have'....
But anyway....
I would like you sway away from the SPEC clutch, and go for an ACT or HKS or something....i cant tell you exactly what to do, because i dont know what the car is being used for or your driving style...but i'd rather see you go for something that is proven, and not new to the market, with some shanty reviews so far...
I have a Greddy Radiator. I needed it because there was an event i was running 2 days away, and all the KOYO were backordered....i pay cost for it..and it was still way overpriced... YEs its beaaautiful, and matches the greddy fmic very well...but really there is no logical reason to pay 500+ for a radiator...i would try and find a KOYO, and have that extra money for other mods...for $200 savings, the perfomance you will recieve is not noticably different. Buy the Blitz upper radiator hose with the tap for water temperature gauge.
Buy EGT, Oil pressure, boost, and water temperature gauges.
You dont 'need' a Greddy FMIC either, if you have access to get piping, the APexi skyline cores are really the way to go...but for convinience, the greddy kits are nice.
APexi N1's are very popular, HKS makes a nice exhaust....if you want something different, and "gangsta"

, we now sell RS*R exhaust.
I'd say run the HKS SS bov.
but your not going to make 300whp without upgrading that turbo, injectors, and MAFS, with something to adjust fuel (tuned ecu, or Apexi S-AFC.)
You also should add some electric fans to your equation.
Test pipe, or highflow CAT.
might want to consider doing brakes and some suspension also
Have a good day