I ran a Viair 480 Dual Pack to a set of 7 gallons on the last dually I did. It filled up fairly quick. I was running 200 psi on the accuair pressure switch.
slammedxonair
+1y
For 7 gallons a Viair 380 dual pack would be the maximum volume I would really recommend, followed by a 444 dual pack and a 480 dual pack (both have very similar CFM ratings and amp draw. Or AZ OB2 is also an option, I prefer Viair, I sell them probably 99-1 AZ