62 Plymouth, 727, 3.23 741 rear gears, P195/75R14 tires (25.5"). I have the green pinion in it, 20 tooth, which should be correct but is not. Speedometer shows 9mph high at 60mph. (Driving GPS verified 60mph, but speedo shows 69mph).
Do I need a higher tooth or lower tooth pinion to get it right?
Do I need a higher tooth or lower tooth pinion to get it right?
