12 mpg Help!!

[OrangeAnimal]

I drove my truck this weekend to houston and back. About 220 miles round trip. Burned almost 2 tanks of gas. 16 gallon tank. The engine is pretty much stock. 350 4 bolt main, RV cam (wish I had specs) Flat top pistons, 1.94/1.50 valves stock heads. Edelbrock Performer EPS intake, Edlebrock Performer Carb. Timing is set base 8*, Vacuum Advance hooked to full vacuum limited to 14* at idle, My full mechanical timing is 32* My full vacuum timing no load is 42* degrees. I spent alot of time working on it and have not gotten the mileage any better. My rear end is a 3.07 open diff. I am lowered 5/7 running 20's with a 28 inch total tire diameter. At 65 mph I am running 2300 rpm could this be the culprit? I didn't think is was too high rpm.

I Figured this thing would get better mileage than this. I could be wrong though. I guess it could be a jetting issue as well. It's a 1406 carb. Anyone have a good starting point for the jetting or should I ditch this for the Fuel injection if I am looking for mileage? I also noticed one other issue. It is too rich once it's warmed up good floods easy when try to start it. I hadn't ever had this problem b4 the trip to Houston. Any thoughts or ideas would be great.