Calibrating VDO speedometer?

[jooset]

Have VDO programmable speedometer installed. Appears to be working fine but want to calibrate it to check accuracy. What's the best way? Two of the methods described in the directions are:
1. AUTO - just by driving a known 1 mile distance.
2. MANUAL - by setting the pulses-per-mile.

Anybody know the exact pulses per mile of the 87GN? Or should I just head out to the highway mile markers (don't know if those are accurate enough). Suggestions welcome.

Thanks,
Matt

 

[marred4life]

I put a electronic vdo speedo on a golf cart . I did the drive exactlly 1 mile thing , Had a buddy drive a head of me with a service truck ( known good speedo calibration ) me folowing him and he stopped when we hit exactlly 1 mile ., Worked good.