I know that some of us have used 91Octane with a 93 Tune on just a CAI, no big deal. But can I run 93Octane with a 91Tune on my S/Cer? The reason is that I would like to see if Brent changed my 91 Tune when he retuned my 93. If the tunes are different, I would like to see which one I like better. I know that 91 is still considered a premium fuel, but, I don't want to gamble it with the S/C.

Thanks.

 

Running 93 octane on a 91 octane tune is cheap insurance to help prevent pre-ignition. If you ever go to the track watch some of the boosted guys, they put a gallon or so of race gas in just for insurance.

Running 91 octane on a 93 octane tune can be problematic.

 

thanks, zip