No E85.... that means larger turbo to hit your goals on pump gas. A simple rotated GT3582R on like 26psi will easily get you over 400whp and spool up faster than a stock location FPBlack. The largest stock location I'd go is like a FPGreen/PTE 55mm stock location upgrade. Anything after that I'd go rotated. You should up your injectors. You can keep your stock rails, but up the fuel press regulator to help your fuel pump. Get rid of that GFB BOV if it's leaking. You may need to convert to FMIC.
if you want 400whp, shoot for 450.