I wouldn't recommend using a single barrel since you have put a cam in it and I don't know what other mods besides intake and headers you have done. I'd do a 500 cfm holley 2 barrel with the clifford adapter plate. The way your engine is now you should be able to get 17 miles per gallon cruising...unless you live in a hilly area or in the city?



1964 C20 LWB 292 6 cyl/sm420 parts truck.
1966 C10 SWB 292 hotrod 6/TKO600 tremec 5 speed.
1964 GMC 1500 LWB 305E V6/ SM420 "Crustine"
1977 C20 LWB 496/turbo400(soon to be 572)
My youtube channel: https://www.youtube.com/channel/UC_hdwhPFzfzpcUXyK_5-uiw