> If my goal was to maximize gas mileage over a 100 mile stretch (i.e.,
> minimize gas usage to cover the 100 miles), I would not be at all
> surprised if my best bet was to climb a very steep hill for the first
> 10-20 miles, then shut off the engine (or let it idle) and coast down a
> shallower 80 mile hill, leaving me at my original altitude, probably at
> well over the normal 20 mpg.
>

Certainly seems plausible for a vanagon. At the end of a slow climb, you've
built up quite a store of potential energy, and with these feeble engines
you probably wouldn't have seen a lot of heavy wind resistance while doing
it! Seems like it'd be a simple question of whether the savings up front
outweigh the added inefficiency. With a manual, surely; but automatic, maybe
not. Seems to me that the biggest efficiency clobbering act is shoving that
square, blunt face down the road at 70mph instead of (say) 55mph. I get a
consistent 15mpg, but I have an automatic transmission, a tendency to
jackrabbit start on green lights, a subtle "1-in-100 or so ignition events"
periodic misfire problem that befuddles the O2 sensor reading and makes the
ECU run it a bit rich, and a driving schedule that sees me either A) drive 5
minutes to work, never letting the engine get warm; or B) drive 30+ miles at
over 70mph. I'm surprised it's as good as it is. I think to get good mileage
all you need to do is EXACTLY what I am not doing...

--
John Bange
'90 Vanagon - "Geldsauger"