Thread: road speed

I'm fairly sure there is no way to correct speed in the Nanocom One, so I'm guessing you have an Evo. It's possible that the correction factor was changed when the Nanocom was repaired. If the coefficient is set to something other than 1 the speed correction has been adjusted.

This is from the Change log for TD5.inst v1.02:

The road speed has a coefficent value to calibrate it when the tyre dimension is not standard or the customer want to show the value in miles instead of Kilometers.

How the road speed coefficent work?

the speed is read as KM/h from the ECU and it is correct for the 7.50 tyres.
this read value is multiplyed by tis coefficent and it is showed in the display.
for example: read sepeed = 100 coeficent 1,05 => 100*1.05=105.


How to calculate the coefficent:
Set the coefficent to 1

Drive to a constant speed and read the speed of the nanocom and the speed read with a GPS(to be considered right)
coefficent = GPS speed/Nanocom speed(with coeff=1)

NOTE:Valid for KM and miles

or:

measure the height of a 7.50 and the height of the bigger tyre. coeff = Big tyre/7.50tyre.
NOTE: the standard miles coefficent must be miltiplyed to the calculated coefficient. The standard miles coefficent is calculated by 1000/(meters for 1 miles).

Hi All,

I fitted Cooper STT 245/75 16 to my Disco 2 (originally 235/70 16), and, of course, the speedo is out.

Is it possible to re-calibrate the speedo with one of those diagnostic computers?

Cheers

No, you'll need a speed corrector. Try searching the forum for truspeed.

cheers
Paul