With the stage 2 comp cam it states that you need to change the gears and the converter. What does this mean?

The need to change the "gears" refers to the gear set in the differential, in particular going for a gear set with a shorter (numerically higher) ratio than the factory item. To elaborate, we would suggest either a 3.45:1 or 3.7:1 ratio diff/differential gear set, up from the standard 3.08:1 ratio set. The need to change the "converter" refers to the torque converter in the auto/automatic transmission, in particular going for a torque converter with a higher stall speed than the factory item. For more information about torque converter stall speed, please check out the link below:

http://www.hughesperformance.com/index.php?option=com_content