I need more power out of my 5.7 vortex

Headers and a better camshaft. Change the gear ratio in the rear end. What is the needed power for? Camshaft for towing ect. Better exhaust. Transmission built for towing or racing, better upgraded Torque Converter for what you need either towing or street/strip.

JET Stage 2 Ignition Performance Module.

Full Flow Exhaust.

Performance Throttle body or cut or take off the diffuser from the one you have on it.

But without the diffuser some say it runs lean, too much air but I believe the computer will figure this out and add fuel to the mix as some performance motors do not have a diffuser at all.

MSD Ignition, Pro digital Multi-Channel Racing Ignition Kit lets you tune in a custom timing curve to match your engine's requirements.

Without going into motor could do a supercharger.