Hi folks, me again, and again, and again....I never thought there would be so many issues owning a Turn Key Survivor car...everythings been done, sometimes twice and yet more goes wrong....

Not sure if people recognize my name but I own the 69 SportsRoof with a 351W moded (not stroked), Full MSD Ignition, T5 Super Duty, 3.73 Auburn Limited Slip with a 750Edel Carb...
Now, this was the second rebuild in less than a decade for this street car (disaster and now has cost me almost $12k) and whats happening is:

At lower RPM's, when throttled somewhat aggressively - to - full WOT, I get pinging.....if this is unclear I'll try with numbers.  ie 1st gear never Pinging start to finish, but If I shift early and the rpm's are lower, speed is slower and I try to do a rapid change I get a quick moment of Pinging......the Worst of it starts after 3rd!  as I climb gears and the rpm's are under around 2200, and my speed is modest to slower, I get a lot more pinging, until the rpm's Climb, then nothing right to 6500 (and maybe more??? never tried past that).

Ive never experienced this so not sure other than retarding the timing across the entire spectrum, which just seems strange given it happens at time Ive never heard or seen before on any cars...esp mine over the past 10yrs after converting it to the T5.

*All I had attempted to do to try and rectify thus far is put my Distributor back to Stock springs and used the Purple Cam which if memory serves me correctly reduced the timing to 18deg max (over the blue cam which was 21 I think)

many thanks,
Jeff