My original tank of gas distance to empty was ~680 miles to empty when I first got the truck.
It got like ~430 miles. I assumed this was 87 octane that the dealer filled up, and for my first fuel up, I refilled with 87 octane. It got another ~430 miles so this confirmed that it was 87.
I haven't really bought used premium before, so I used the website find93 to find 93 octane near me, and by coincidence I went to shell first. Shell had V nitro power 93 at $4.70 per gallon. That is WILDY expensive. 87 was $3.00 per gallon. For science purposes I put V power in there and the ECU attempted to relearn the miles to empty. I assume it got a bump in the horsepower numbers, to the advertised 450, and the MPG got better. 87 was giving me ~13.8 and 93 is giving me ~16.2 mpg.
But I just dont think the detergent they put in there is worth it. I refilled up at sunoco 93 octane at $3.60 per gallon, and they advertise as nascar fuel. Im going to end up trading this raptor in for the R anyways, and the miniscule cleaning that it advertises it does is just not worth it on a trade in truck like this. In my opinion anyways...
On a side note, does anyone know how much octane the PCM can learn & adjusts to until its limit. Can we put octane boosters upto ~98 octane and the pcm actually adjusts timing and makes use of that? What is the limit of timing the PCM can actually do with respect to octane - definitely 87 to 93 but can it learn above 93.