Speedo Calibration Form

Speedometer Recalibration

1) Pre-War or Limited Slip Differential

Jack up one rear wheel. Chock other rear wheel. Measure circumference of tyre on raised wheel and note below. Remove jack and chocks. Make a mark on the tyre (eg by the valve). Remove speedometer from dashboard and place flag (eg masking tape) on exposed end of inner speedometer cable. Push car forward  for  6 complete revolutions of rear wheels and have an assistant count carefully the number of times the speedometer cable turns and note below. It is best to repeat this several times and reach an average answer. The more accurately this is done the more accurate the recalibration.

2) All other types

Jack up one rear wheel. Chock other rear wheel. Measure circumference of tyre on raised wheel and note below.  Make a mark on the tyre (eg by the valve). Remove speedometer from dashboard and place flag (eg masking tape) on exposed end of inner speedometer cable. Turn raised rear wheel for 20 complete revolutions and have an assistant count carefully the number of times the speedometer cable turns and note below. It is best to repeat this several times and reach an average answer. The more accurately this is done the more accurate the recalibration.

Enter info below :-