I'm running 13.5 psi max on the SD via adjustment of the wastegate.

I don't believe that the additional pressure above about 11.5 is accomplishing anything other than to heat the air higher than necessary. The ALDA has a fixed range and it's met the end of that range well before 13.5 psi.

Since you have the controller, I'd be interested if the 0-60 time is affected at all by an adjustment down to 11.5. I'll bet that it is not, provided that the ALDA has been tweaked for more fuel off idle.