I was getting about 15 with my 305 and out of tune E4M Q-jet. I expect better with my 350 and Edelbrock #1406 (yes, I cheaped out and decided to stick with carb over EFI). I would think the difference between a dialed-in Q-Jet and a dailed-in Edelbrock couldn't be more than 1 mpg. (i hope)
By the way if you want to rebuild and tune a Q-Jet. Pick up a copy of Doug Roe's
Rochester Carburetors. A valuable tool for messing around with these carbs.
1
