mcdelaug:

I’m not saying it does, but increasing boost and monitoring for preignition would be a way to “test” for higher octane fuel... I know you’re aware that timing retardation when knock is heard is how most engines “detect” lower quality fuel...

 

If the factory did not tune the ECU to take advantage of higher octane fuel than retail stuff, then there will be absolutely zero benefits in running higher octane fuel than what the factory spec for.

The only time higher octane fuel would help for a car that's is not tuned for high octane is when the engine is running too hot and the regular fuel was knocking. 

Unless someone fuelled up at Penny Gas or Discount Gas or something, low quality fuel is pretty much non-existence. Chevron, Shell, etc, all national name brands have their standard and they are pretty much spot on. 

 


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