Good routes, good car, good weather, etc...
I don't mean to be depressing. Actually, I want to show what is possible. And like Denis said, what should be possible without so much work.
The car could be better, actually. The gear ratios are too short - 60 mph is running 2500 rpm, when it could very easily maintain cruise speed at 1500 rpm. I've actually considered a VX/CX trans swap to get closer to that goal.
The aerodynamics aren't great - cd .36 - but I handle that by driving SLOW! Scangauge reported average is 25 mph, so counting for stops it's about 30 mph.
