Here’s an idea that I’d like to hear seconded and or refuted:
Octane is resistance to auto-ignition. Compression ratio is relevant, because compressing a gas adiabatically (assuming no heat transfer, reasonably accurate here) will up the temp, the higher the compression, the higher the temp.
But, as the FINAL temp is dependant on INITAL temp (the abient temp at the air intake), couldn’t you try “good stuff in summer/cheap stuff in winter”? also, would a cold-air intake allow the use of lower-octane gas?
In my old '95 Nissan SE-R (spec’d for 87), I’d occasionally notice light pinging, but ONLY under load on hot days.