Discos have the aerodynamics roughly equvalent to the exxon valdez, and leak about the same amount of oil. Keep her at 70mph, comfy zone. keep the alignment, tire pressure, drive oils, air filter condition, plugs/o2s and drive like theres an egg under the gas pedal and youll see improvements.

 

You can also carefully bend the window frames a little to tighten them against the seals more.

 

I wouldn't trust UG mileage unless I'd checked it against odometer derived mileage.

I've been running non-ethanol 93 octane and getting >15.5 mpg with some miles on the hwy. I was getting ~13 mpg running 87 octane ethanol laced gas.

 

65mph all the time work best for me, 15-16mpg avg. although i have dropped mpg the last month, the o2 sensors and/or Maf helps from others experiences.

 

Oh if we could only find non-ethanol gas here!

 

yeah, I have new O2's (front) and a new MAF, had hoped for better mpg. it's ethanol 'enhanced' fuel around here, always use 93.

 

I use 85/87. Cheapest gas possible. Makes up for bad fuel economy.

 

Check for disc calipers dragging.
After a time of steady freeway driving, bring it coasting to a stop without applying brakes at all, pull to the side of the road ( except some hand brake ) and touch the discs. If you burn your knuckles, there is a stuck caliper robbing your fuel. No discs should be hot, perhaps warm to touch.
Am always 17 to 19 mpg, but did other modifications.

 

17-19? ^_- Do you only drive downhill and winch back up?

 

What other modifications did you do?