New engine issues

So we have a small block that hesitates or won’t rev up very much at all? What is the total timing and at what rpm is it all in at? I have never seen a stock fuel pump sink a float. Also at higher rpm when the pump is pumping more the motor is using more. I don’t think The “simple” stuff has been checked yet. What does it do when you try to bring the rpm up? Pop/snort or just cuts out?