Holley/Demon Carb stumble

So i could just remove one of the line off of the carb and turn my pump on Right?

Without a way to restrict the flow coming out of the hose, the system pressure will be zero if you just dump the end of the hose into a container.

What it flows at zero pressure is of zero importance.

What you need to know is what it flows while maintaining the correct system pressure..... which is where the ball valve comes in.