Old man old Vette

The ls 2 is for the intake only. I already have the motor. Sorry........

Okd

So I've been reading and a little confused I have a stock LS 4 with a ported throttle body and bored out exhaust ported intake Runners on heads is any of the intake manifold better than the lS4 and how much horsepower difference which one is the best not ready to do a cam yet but wanted to do the next step away from stock please help!
I have you efi live and shut off the dod.
So what is next as far as intake is concerned thank you