[gofarthergen6]

Just looking over some high performance recommendations from Chevrolet, it says to consider using 100 octane if track temps are 86 degrees Fahrenheit or above - is it meaningless if the track temperatures aren't expected to hit high 60's?

This is for a stock ZL1 1LE, no tuning for fuel.

[Joshinator99]

The higher the intake air temps, the more likely you are to experience preignition and timing retard. Running some 100 octane helps prevent the timing retard which helps stop power loss. That’s not to say the high octane fuel is useless below those temps, but if the car is not retarding timing then the extra octane isn’t helping.

[JSH]

Originally Posted by gofarthergen6

Just looking over some high performance recommendations from Chevrolet, it says to consider using 100 octane if track temps are 86 degrees Fahrenheit or above - is it meaningless if the track temperatures aren't expected to hit high 60's?

This is for a stock ZL1 1LE, no tuning for fuel.

Only if and when you put an aggressive tune in your stock motor with a lot of advance and/or high A/F ratio. Otherwise, no.