I just bought a 1981 F150 Custom with a 351m. I'm trying to clean up and organize a busy nasty engine bay. I have one pump I assume originally meant for Emissions. But it has no belt to it, and isn't being used. It seems to tie into a few different places and being unfamiliar with these engines I'm not sure what can be removed altogether, and what I need to reroute.
That pump, and its attendant piping, is the secondary air injection pump (or smog pump). I believe that it can be plugged, with some work; it's not a simple matter of removing the pump and fittings because it opens into the exhaust flow. It's vacuum-controlled, and the vacuum hoses can probably be disconnected and plugged at the source.
Thank you it appears to pipe into the intake. I figure plug there to block it off should suffice and just cap the vac lines as you suggested? Please correct me if I'm mistaken. I'll be tearing into it tomorrow as well as removing the carburetor for a rebuild in a couple of days.