Drag strip launch problem

I would also try the Demon first, your combo seems pretty stout and I wouldn't be surprised if your Edelbrock and/or Thermoquad need some mods to work. Usually fuel delivery problems show up at the big end, there should be enough reserve fuel in the bowls to handle the launch.

But yes your fuel system can only flow as much as the smallest part and it sounds like you have different sizes throughout; it should all be the same size at least 3/8" all the way.