Matthew Burr

hey everyone, i have an 86 f150 that i put a used head on after i cracked the original; its got adjustable valves now which i got just tight enough that the clatter went away and they wont loosen. im pretty sure the intake warped which i managed to plug with some high temp gasket sealant; put a prof rebuilt carb on it and redid all the vac lines according to the diagram. it is the feedback carb with a brand new oxygen sensor in the exhaust. it has a steady vacuum of 19 on the gauge but dips to nearly 10 when i initially give it gas, its also got a bit of a rough idle once its off the fast idle screw; am i still having vac issues at the manifold or could i be missing something else? thanks for any input