Non-ethanol vs 93

dartfreak75 said

Im curious for yalls opinion on the matter. For a 10:1 compression engine would you go for non ethanol at 89 octane or premium 93 with ethanol?

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If those are the only two choices you have, the motor may decide for you. You'll be able to run the non-EtH 89 for break in because it's not under load. Once you load it, it may knock with the 89 at 10.3:1 with iron heads.