I've owned a 1987 Carrera for about four years. The speedo registers about 10-15% high, and I assume it's adding 10-15% to my mileage on my odometer. I'm thinking it's related to the 15" wheel that came with the car. Can I replace some gear or doohickey in the speedo to get correct readings?
My passengers get this funny look when they look and see 100 mph!
Thanks, Steve

 

Isn't there somebody out there that can answer this question for me?

 

I replaced a set of 15" Fuchs wheels with 16" Fuchs but have not noticed any problem with my speedo calibration. I will check it out with my GPS unit next time I have the car out. As far as fixing the problem, contact one of the speed shops that specialize in repairing these units - "Palo Alto" seems to ring a bell.

I will let you know what I findwith my car.

Mick

 

The 911 speedometers were naturally about 10% higher than registered speed. It was too keep you from getting in trouble. The odometer should not be affected.