Originally Posted By: glennc
My particular E30 is extremely sensitive to air density. At sea level I can barely eke out 25mpg while up here at 5850ft I average 30-32. I actually get my best mileages in mountain driving.
What variety of E30 is yours?
My W126 Mercedes, the big S-Class from the '80s with a 4.2 liter V-8, was just like that. At Denver's altitude of about 5200, I got 18.5-20 mpg on the average. Down in The Swamp (a lot of which is *below* sea level), my mileage dropped to 17.5-18.