MSefi.com read only forum (Jan.15,2018)

I'm looking at my first dive into the EFI world.
It looks like the MSII is what I'll need to run my 355/nos(progressive/2 stage control.. not feed fuel through injectors /2step/etc
for a hotter than most engine would mass air or speed dense. be a better set up..
#2 how does one figure the size ...