I have been using 550cc injectors for several years, they work great. that one change w larger fuel pump
eliminates messing with by pass setups, regulators looped rail extra parts etc.
get a larger fuel pump with the 550cc injectors easiest way and happens to be more economical in my case
now you are ready for a real dynotune instead of a canned one.
in short 550cc injectors, and a bigger pump. the end
ii am running stacked pullies 181 lower and a 65 ec upper.
no issues after tuning besides a smoother running engine.