spedo error
 

my speedo reads about 10 mph faster then real world time. Is this normal Porsche ticket limiter?
Would like some clues here as to what might cause this.
maybe someone put in a diff ring and pinion ?

Conventional wisdom is that Porsche speedos will usually read about 5 mph fast. This is affected by your wheel and tire choice of course. The speedo is internally adjustable if you care to take it apart.

ianc

hmmm take it apart???????/will it be sort of obvious??

You need to (carefully) pry the back side of the black bezel off the lip of the gauge itself to let you get at the guts of the gauge. once the circuit board inside is exposed, there's an adjustable pot you can tweak to change the speedo reading for a given input from the speedo sensor. If you search here you'll find some more info about it,

ianc

Thankyou

I compared mine to my GPS while on the interstate (82SC) and above 45mph the error was about 5 mph OVERstated.

Paul

My 82 SC speedo reads about 10% fast. Trip meter quit this summer. Plan to have the speedo send to

http://www.nhspeedometer.com/index.htm

or

http://www.paspeedo.com/about.htm

during the winter sleep.