Originally Posted by
Nexus
Fitted with 225/45; Through a 5K speedo check, odometer is almost spot on, fractionally understates distance by maybe 100m at most over the 5k (2% error). Error is closer to 50m I think (1%) or less. with 215/45 odo is within 0.1%
Comparing against GPS, I see approx 7.5% speedo error with 225/45 fitted. With 215/45 it's 8.5/9%
Oh, yes - I don't think calibrating the speedo guage would have any effect on the odo because the odo is a value read straight from the ECU. The speedo guage however has to convert a digital value to an analogue display and that is where the error is, not in the digital data. We know the digital data is correct...the analogue display is not.