"Does anybody else have problems with their Boxster speedo reading way too high? My speedo is about 6klms fast at 60 and 12 klms fast at 120klms - so its 10% out always."
Mine used to be more out, but depnds on what has been going on with wheels and tires. When I had the original 17" wheels on the car, as I recall, their was a fair deviation in the speedo reading and the actual speed. These days with 18" aftermarket wheels and PS2 tires, it is very close within 1mph based on the gps unit in the car.
Ed