Correct, the calibration is at the speedo. The VDO speedo has a choice of inputing the pulses per mile or by a procedure involving driving an exact mile.
I'm no longer driving the speedo via the ECU as I've stripped out the Ford ECU and installed an OMEX 600 as a precursor to doing some engine tuning work.
I've already installed the Librands Manifold then re-mapped on the Dyno to get 127 HP instead of the standard Ford 115 HP.
So now my Speedo will drive directly from the Hall Effect Sensor on the hub.
My rough calc is about 4100 pulses per mile with the 5 bolt hub but I haven't double checked that yet.
When I've got the rough calibration correct I'll do a more accurate GPS distance and speed check.
At some point I will probably change to 175/70R15 tyres so I can re-calibrate it again then.
