I thought pretty much all motor vehicles got maximum fuel efficiency at
50-55 mph.  Wasn't that the point of Jimmy Carter reducing speed limits to
55 in the 70s, to reduce fuel use?

Joy

On Sat, Feb 4, 2012 at 2:48 PM, Loren Busch <starwagen@gmail.com> wrote:

> I returned earlier this week from a long trip, odometer says 3,800+ miles.
> Driving a '90 Westy with stock engine, automatic tranny, 167,000 on the
> original engine, only major work ever done was reseal heads at 88,000. And
> a new (yeah, NEW) AFM installed just before the start of the trip. For the
> first 2/3 of those miles I was either pushing it to meet a schedule,
> freeway and highway speeds 60-70.  And getting as low as 15.5 mpg on one
> tank, most segments 16-17 mpg.  Then on the way home no rush and no
> schedule, I set the cruise control to 55 mph and cruised in the right lane
> no matter what the speed limit was.  I did the last 450 or so miles that
> way.  And the mileage for that part of the trip was just a little over 20
> mpg!!
> This confirms, at least for me, the statement that comes up from time to
> time that our Vanagons were engineered during the time that the highway
> speed limits were 55.  And that is where the WBX engines like to run.
> And seriously YMMV.
>