Erratic Timing

For example, acceptable timing range for '68 using 5* initial (per Plymouth FSM)
upload_2019-3-21_21-22-9.png

CAP and CAS 318's at least through '69 have the initial timing spec'd at either TDC or 5* ATC.
From 1400 rpm to 4600 rpm the timing very similar to the non-smogged 318 shown above.