I have an 83 with a 5.0 and of course the 4bbl carb. When I got it I didnt know much about it. The problem is when I kick it down it doesnt seem to really want to GO. At about 4000 rpms it starts to die down and kind of bog down. What could this be? The 4 barrel isnt opening maybe? There are two vaccuum lines disconnected so....?? Any help would be cool.
Thanks  

I am not the smartest person when it comes to carbs, but if there are disconnected vacuum lines, and the carburetor features vacuum secondaries, you could be correct on your assumption. I would trace the disconnected vacuum lines first, and get them sorted. Once you know all vacuum lines are accounted for, then you'll have a more clear understanding of what may be wrong.