Toluene for octane
Never liked tolulene myself.
Kept the engine from pinging but it seemed to make the engine lazy revving too.
I've used a bottle of 104+ octane in 10 gallons of gas for over 20+ years and it has always worked well for me, better than any supposed race gas I bought out of a gas pump.
My main test engine was a 340 11-1 with iron heads and total timing set to 35degrees