BigDaddy, If you selected your Carbon Express arrows using the chart supplied by that manufacturer for your set up, as I'm sure you did. You have a perfect match as stated above. In many situations you can actually use one size weaker spine. Manufacturers tend to stay to the heavy side in there recommendations. One more little detail. I don't reply to a post unless I know the answer from experience. Too many people like to blow smoke based on opinion not experience.
Good Hunting...