Rusty that is strange
I have had the same thoughts
I am currently running 34* all in at around 2800 rpm with vacuum advance that adds 10* at cruz speed, all FBO ignition.
91 octane pump fuel, no ethanol.
No detonation, not even one ping.
Explain that for an iron head 340.
Perhaps the 9.5 CR is the answer?
all FBO does that mean distributor as well ,? that may be part of why you are not pinging , put in a stock distributor and see what happens . i'm having a distributor done by them now hope it helps
