[55blacktie]

I watched the Engine Masters episode as well. However, the bottom line for their tests is that there's no real gain in using a higher octane fuel than what an engine requires. Nevertheless, timing, carb tuning, spark plug range can change the fuel needs of an engine. My 2017 Ram 1500 Hemi runs fine on 87/w 10% ethanol; that's what Chrysler recommends, but were talking about a modern EFI computer-controlled engine. A 292 Y-block/w big-valve heads, bigger cam, bigger carb, and raised compression might need more.