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If you would like to understand your VSS and the impact that changing tire size, differential gear ratios and speedometer gearing, or any combination will have, then click
here.
If you would like to figure out where to set your Speedcal or Recalibrator switches given different combinations of tires, gears and speedometer gears, click
here.
If you want to know what the RPM of an 03/04 Cobra Eaton blower will be at a given engine RPM with any pulley combination, click
here.