I have not seen any pitch changes at all, sounds like you may have been a bit tail heavy.

I need to measure the pipe.

55ozs would help I only have 48oz plus the header, not much room to fit a tank in the AMD Hawk, and I don't think I would like it in the space in front of the ducts due to the CG change, where I have my two 24oz you don't notice anything as they empty.