Power and efficiency difference with lower octane levels?

[sk47]

I am a self-admitted barbarian. I wash my car using only one bucket, etc. I have 70K miles on my 2019 GT and have only run premium in it for a couple of tankfuls while at high altitudes on a Route 66 trip. I always try to do a couple of pulls to redline in 2nd and 3rd on a weekly basis to "blow the carbon out." My engine shows no ill effects from a steady diet of regular gas. I typically am using "top tier" gas which has a better detergent package, but no higher octane.

Also: https://www.caranddriver.com/features/a28565486/honda-cr-v-vs-bmw-m5-ford-f-150-dodge-charger/

Hello; from the link.
"the engine controller calculates an inferred octane with closed-loop logic that continuously advances the ignition timing until it detects knock,"

This explains a previous post in which a member states there will be knock even on 93 octane fuel.

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[Robottrainer]

Hey folks. I've tried checking the owner's manual for the answer to this question, and tried searching this forum, but I'm struggling to find anything conclusive.

I remember Ford in some TSB or maybe even in the official owner's manual for my previous 2015 S550 GT said that the car would only take about a 1% hit in both gas mileage and power when using "regular" 87 octane instead of the recommended 91 octane. It's been a long time, so I can't remember exactly where I saw it, but I'm confident it was reported by Ford. It was such a small difference that basically whenever I wasn't going to the track, I would happily just get regular gas.

Does anyone know if there is any remotely official number like this for the 5.0 in our Mach 1s (and presumably for Bullitts from this gen)? I know this one uses direct injection and I believe a higher compression ratio, so it probably takes a bigger hit with 87 octane, but I'm curious how much? And/or has anyone dyno'd the car at different octanes?

Sometimes when I'm on a road trip and stop at certain gas stations with absolutely outrageous markups for 93, I wouldn't mind cheaping out. Often just out of principle. I don't need to drive it at 10/10ths on the freeway. But I am curious exactly what I'm giving up... And I don't know why I waited nearly four years to ask this question.

You wont gain anything feom one octane to another unless it starts pinging and the engine pulls timing.

I run 93 as I want a good hedge to prevent pinging.

 

[Pony2015]

Trust me when I say that everyone has an opinion on this, often a strong one. Mine at this LINK. Probably more than you wanted to know . . .

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