Does it by any chance go to the choke stove either in the intake next to the carburetor or exhaust manifold? If so that would be the fresh air inlet for the choke. Open to the air won't hurt, but if it is it should connect to the small nipple on the back of the carburetor top so it's air comes from inside the filter.
"Getting old is inevitable, growing up is optional"
Darth Vader 1986 F350 460 converted to MAF/SEFI, E4OD 12X3 1/2 rear brakes, traction loc 3:55 gear, 160 amp 3G alternator
Wife's 2011 Flex Limited
Daily Driver 2009 Flex Limited with factory tow package
Project car 1986 Chrysler LeBaron convertible 2.2L Turbo II, modified A413
Look at your vacuum diagram.
There's nothing attached at the back, where the EGR is.
Jim,
Lil'Red is a '87 F250 HD, 4.10's, 1356 4x4, Zf-5, 3G, PMGR, Saginaw PS, desmogged with a Holley 80508 and Performer intake.
Too much other stuff to mention.