Some suggestions. I wouldn't consider myself a fuels chemist, but I am a hazardous materials chemist with 30 odd years work in the field. And a car crafter (Hot Rodder if you're over 50)
High compression motors and available fuel.
Or perhaps you've played with the numbers on Dyno 2000. Two identical engines. One running 9.5:1, and one with 11.5:1. Everything else being equal, which will be the faster car.
But we can't get Super Shell, or Sunoco 260 at the pump anymore (much less for $.32/gal). But when you try to run it on 93 octane pump gas, it rattles like a coffee can full of ball bearings.
Toluene and xylene are both used in carburetor cleaners. Not sure there's any anti-knock benefit. Moth balls were used for this at one time with dubious results.
Things NOT to burn in your expensive race engine. Laquer thinner, mineral spirits, diesel fuel, automatic transmission fluid. Or any other concoctions or home brews unless the person doing the brewing knows what he/she is doing.
And no MoS2 (molybdinum disulfide) or teflon in the
oil. Mos2 is a cam lube, and helps for engine break in. So does GM EOS. After break in, it's no help.
Although polymer coating high frictionengine components is a different story, it can't be done by pouring it in the crankcase.
Like the man said, there's no magic bullet for ping profing your 11:1 motor except the stuff that was designed for it in the first place. Racing gas. Union76 has it. Many speed shops have it. Start with a ratio of 1/10 racing fuel and 93 octane, and up the ratio until the engine smooths out. Upping the ratio any more is like running your grocery getter on 93 octane.
I've never tried aviation gasoline mixtures so can't personally say if it works or not.