remember you that wind resistance is a square function of velocity, and power is a cube function.

martin jagersand's power vs speed measurements shoudl be taped to the dash to remind us:

(http://gerry.vanagon.com/cgi-bin/wa.exe?A2=ind9812E&L=vanagon&P=R3587)

      Speed (m/s)  Total drag (kW)
      ----------------------------
         15.00         -7.99
         20.00        -19.69
         25.00        -34.74
         30.00        -53.15

(25m/s is approx 56 mph)

alistair

On 2012-02-04, at 10:18 AM, Loren Busch 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.