Carb and trans issues, vacuum?

Google reviels that corvette guys love parts numbers and this is a 75-77 ish carb. Probably off a truck

 

Here's a wiki on quadrajets.
Yours id a 75 truck manual tranny carb.
Lots of info.
http://www.crankshaftcoalition.com/...hester_Quadrajet_4MV_carburetor#Trouble_spots

And before I forget.
Your pcv hose running to the chrome cap on the passenger side.
Is it a pcv or just a chrome cap with a hose barb on it?

 

It's got a valve in it, thanks for the link