I was getting some pinging when I was in 3rd or 4th gear and I decided to punch it. The extra strain or the drop in vacuum caused some slight pinging for a sec. It has been slight and only occurs with wide open throttle.
I was originally running 12 degrees advance and moved it back to 9 degrees. This helped but still very slight pinging. The car still was doing great with 9 degrees advance.
Yesterday I added 2 gallons of 110 octane to a tank of 93 octane. From my calculations I ended up with 95 octane. There was no pinging whatsoever.
Not sure where to go from here. Maybe drop the advance to 7-8 and try again. I still have my original distributer that I recurved that I have not dropped in yet. I may have to try it soon and see if it may be better.
If you ever want to mix your fuel to achieve higher octane below is the calculation.
Mixed Octane = ((fuel1Octane x fuel1Gallons) + (fuel2Octane x fuel2Gallons) ) / (total number of gallons)