91 no ethanol or 93 with?

[BOP4ever]

Wondering which would be better for my car running 24 psi with alcohol.
I filled up on the 91 today fwiw no retard on a couple hits I made on it after to see .

 

[Eric Stage I]

As long as there's no knock, it doesn't matter. The ethanol is not an issue.

 

[hensleyt]

Octane is the main part of the equation ,Go with the greater number