Need some opinions. I'm getting ready to toss a bunch of shit on my car and need to know what size injectors I should go with. Currently for mod’s I have - K&N filter, Free mods, Custom intake, Magnecore wires, balance shafts removed, under drive pulleys, rewired 190 Walbro fuel pump, MBC at 14 PSI, Evo 3 16G, 2g manifold, .020 95 pistons, Fully rebuilt and balanced 6 bolt, rebuilt tranny.

Next week I’m tossing on Apex N1 3 inch down pipe, catback, and straight pipe, 2.5 O2 housing with atmospheric dump, Dejon tool lower IC pipe, and upper 2.5 inch pipe for a GM blow through setup, Supra side mount intercooler, 3 Gm MAS with Ramchargers translator, and a 2600 act clutch. Should I go with 550cc's or higher? Also is there anything else I should toss into the mix before I get to work on this filthy whore? Should I get a FPR, and what would you guys recommend?

550s should do it for you. It wouldn't hurt to also throw in a 255lph pump and AFPR.

For the same or similar $$, I would go with at least 660s. With the ability to tune using the MAFT, it seems you are only limiting yourself with the 550s. Although you don't need them now, you may choose to upgrade the turbo in the future. Also, the injectors will run cooler and therefore theoretically last longer if operated at a lower duty cycle. My .02

does 550 injectors limit adjustability to your MAF-T setup???

or just limit HP that you can make

if your goal is lets just say 300-400 WHP, are 550's enough???

just curious because I already have 550's and would hate to swap them out again needlessly

Given that my 720s are "suposed" to be enough for 500whp. 550s should be enough for 350-375whp. That is assuming you have enough pump and fuel pressure. Larger injectors are nice, but if your not going to use up the fuel, get an AFPR and turn the pressure down some. 660s can always be scaled down to 550s.