I see said the blind man.

So the new 5.4L would then have to able be able to variable adjust compresion based on actual belnd of ethanol in the fuel? So then if after a full tank of e85, if I put in 100% gasoline then it would detmine this and lower compresion as I drive? Or would it be all or nothing in that if it detects e85 I'm running higher, then if a retailer is not honest and actual mix is "e78" I don't get the benefit? Just some q that pop up in my head.