'87 5spd 5.0...guessing at 2.73 stock gears based on performance.

Doesn't seem to be running rich (no bad smells or black smoke) and I can't find a fuel leak. Anyone have this kind of fuel economy? Did all gaskets on the plenum and the plenum-intake gasket. Idle is mostly smooth and has a nice set or freshly cleaned/tested 19lb injectors. New IAC valve. Set TPS to .98v. Smoke tested and found a tiny bit of smoke from the EGR valve, but when I sprayed carb cleaner around EGR theres is no...

50 miles on 1/2 tank of gas