Running a "03" ultra with stage 1 big bore and power commander. Stock cams, stock pipe headers and 3" internal disc slip-ons.

Currently running 16 in the right and 20 in the left - thinking that the left needs to be more open to do anything. Bike pulls OK but I wonder if it flows enough. Any recommendations?? Plugs look OK - maybe a bit dark - but the PC makes remapping for fuel very easy.