Jim,
keep in mind this LS1 is still fairly stock, stock cam, and the owner wants redline to be at 6,000 RPMs.

Looking at the raw PCM data the injectors as in your case were hitting 100 % dutcy cycle ( 22 ms pulse width) before even getting to that redline and the superchips tuning as you know is not very good for the SC.

Being the boost went to 6.39 max and your ATI is boosting a bit over 7 PSI we have to wait for the larger injectors and my tune to get the numbers better then it is out of the box.