Race gas vs pump gas on lower compression street/strip motor

TT5.9mag said

Elaborate please @YellowRose. I’m not saying you’re wrong, I am saying I am uninformed. One of my girlfriends high school friends is a crew chief for a fuel funny car. In the pits they fire the engine on 87 octane. When I asked why he said “it burns slower”, among a few other things. I’ve always heard that same thing.

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That may have more to do with gasoline not having any Oxygen in the molecular structure. Nitromethane has 2 Oxegen atoms. That oxygen is the same as popping a little nitrous oxide in your street engine. it oxidizes any fuel in the chamber more efficiently... need oxygen to prpmote the burn.

An engine will run better when the octane is just enough to keep out of detonation. When I raced in some restricted forms, I used to tell guys my stuff had a special blend I got from a local refiner specifically for our class. It was from the 91-93 pump at our local 76/Arco/Chevron... etc. When we dyno'd the engines, they ran better on pump swill.