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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You'd be better off going to the Rocket Racing Fuels website and reading about it there.

Pump gas has a different burn rate than race gas, as a run of the mill surface transportation vehicle is lucky to see 4000 RPM every once in a while.

An engine with an 8000 RPM speed needs a fuel with a faster burn rate (which also affects ignition timing) because there is much less time to burn the fuel at that RPM, and if you had a slower burning fuel, you'd be jacking the timing through the roof.

On the same line of thinking, a bracket car shifting at 7000 might need the same octane, but a slower burn rate.

Racing fuel is quite complex.

But burn rate and octane are not tied together. The Rocket website explains it much better than I can.