Indeed.  I see this same disparity on my 1982 with non-stock 15"
aluminums.  My speedo reads about 8km/h (about 5 mph) slower than
actual speed when traveling at 100km/h (62mph)

The GPS has confirmed this same behaviour on my 2001 Honda CR-V so I'm
not too concerned about it - although it's nice to know.

Joe
1982 Vanagon Westfalia
Stratford, ON

On 12-Oct-09, at 7:40 PM, Melissa Mourkas wrote:

I have come to the conclusion that I am not driving as fast as my
speedometer indicates as people are racing around me and my speedo
says I am doing 70 mph (and I thought this 1.9L was just really
peppy!).  I have 15/65/205 tires/wheels.  I have been unable to
conduct a test using mile markers as they are nearly non-existent
around here and, no, I do not own a GPS.  (I like maps). My shift
points seem about 5 mph off the marks on the speedometer as well. I
followed a thread on the Samba regarding this disparity:

http://www.thesamba.com/vw/forum/viewtopic.php?t=345224

They were claiming as much as 10 mph under at 70 mph (actually
traveling at 60 mph).  Has anyone on this list experienced this and
have you tried this ratio-adjusted speedo cable shown in that thread?

The vendor for the adjusted cable is:

http://www.tacomaspeedometer.com/index/index.php?
option=com_content&task=view&id=15&Itemid=28

I apologize if this has been covered ad nauseum in the past.  I will
try to come up with something more original next time.  In the
meantime, thanks to all who choose to reply.

Melissa Mourkas
'84 Westy Honey Bee
Sacramento, CA