mpg 2bbl 5.0

well not exactly a 2 bbl carb, but my '85 Mustang LX 5.0/auto gets around 24 mpg the last (and only time) I checked it. It's CFI.

Mileage will depend on soooo many things. I used to have a '74 Chevy pickup with a nicely built 355 (made ~400 HP) and when gas got above $1.50/gal, I put a factory iron 2 bbl intake and rochester carb back on it. Got worse gas mileage, so I put the Weiand and Holley back on.

I put a 350cfm two barrel holley on my t-5, 3.27-geared, 5.0 recently and am getting the same mileage as my quadrajet. Still gotta dial it in, as I tried turning the idle mixture screws in all the way and it was still running.
What are the smallest size jets made for the holley?
I have the 60's in there now and put a 50cc accelerator pump on it with a center hung float bowl. 15.8 mpg as of last night, when I filled it up.