miss and bogs

I have a 86 carb b2000 w/2200 motor. A few weeks ago it started to I guess you would call it hiccup . It starts fine Idles fine w/a minor miss. I changed the cap,rotor.plugs,wires and fuel filter. I'm gonna check the vacuum lines . With all that it still runs the same. Once its warmed up a few minutes if you give her some gas most of the time it feels like its on boost and then starts to fall flat again.It never stalls on idol . Thanks Ron

Cats plugged?

Check your EGR valve if that has not been touched or checked.Will create that problem.

Thanks guys . Your gonna love this one. Turns out after chasing vacuum lines ,full tune up and carb cleaning and lube all parts . timing was ok I was going out of my mind. I looked down and the lock bolt for the distributor threads somehow were stripped out.. WTF it had been fine for god knows how long and decided it wanted out. lol Now shes running like a top instead of a bottom.