[GTX JOHN]

Since you mentioned the distributor change..........It sounds like that might be
the issue. A lot of Hot rods when you put into gear it lowers the RPM enough
that the plate moves and takes out timing. Play with the weights in MSD or for
testing only lock out the curve complete and see if that cures it. Then you know it is a spring problem.

There are bushings in the plate that can easily
be changed to give more initial advance and less advance in plate. My street cars like more initial
and less in plate = 9 Degree bushings (18 engine).

Of Course I am a Mopar guy......Your experiences may vary!