I went from a stock 20mpg to 22-23 city with a decent amount of getting on it. I run around 38psi in my tires and 38 degree's of timing in the map with egr advance turned off. Timing makes a bit of a difference but don't get carried away. Advanced mivec (28*) in the cruise area helps a little bit as well.
I messed around with forced open loop fueling and leaned out the cruise afr to 15.5 . The idle quality ( even at 14.7) wasn't good and I picked up 1 mpg around town. It wasn't worth it to me so I went back to closed loop.
Its an Evo, its meant to burn fuel.