Forced induction is the way go, just don't expect better mileage.
We live at 4500ft and camp at 9900ft. Round trip nets about 8.7mpg
2013 JayFlight 26RKS
2013 F-150 SuperCrew XLT w/EcoBoost, 4x4, 3.55 E-locker,
firestone airbags in back, windbag behind the wheel,
E rated Michelin LTX M/S2s
"No matter where you go, there you are"