440 what am I missing here?

Just curious, what ignition did you say your running on it? And what headers again? If your wanting to try a converter, I would recommend calling Precision of new Hampton or PTC, Ultimate, Precision, Pro Torque, etc. and get one custom made. It will help, but I would optimize timing first, just to see. The converter will be a band aid for the cam and cylinder pressure but at least it will let getup into the power band and on the pipe quicker.