Is Higher Octane Better
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Denny
Tuned
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From: Queen Creek
Your manual also recommends 91 or better octane for 'best performance' when towing or in hot weather. Just follow what your manual recommends and don't overthink it. Agree with others...nothing less than 87.......
Laughing Gas
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Postmaster
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READ and or search..
< google > why 85 octane in the mountains.
here is 2
https://tap.fremontmotors.com/truste...se-at-altitude
https://www.quora.com/Why-is-regular...ion-U-S-states
< google > why 85 octane in the mountains.
here is 2
https://tap.fremontmotors.com/truste...se-at-altitude
https://www.quora.com/Why-is-regular...ion-U-S-states
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Laughing Gas
Joined: Oct 2017
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What the manual states for using at higher altitude to use HIGHER octane gas doesn't make any sense. Perhaps they assume you are towing/going up hill a lot.
Whatever it is, I've used 85 in many cars at high altitude and it's been fine.
Logistics Pro
Joined: Apr 2000
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From: Mills River
Ford began including the higher AKI recommendation for “best performance” for MY2017 when they introduced the improved 6.2.
I’ve not seen any recommendation to use “higher AKI fuel at higher elevations”.
HTH,
Jim / crewzer
Cargo Master
Joined: Jan 2004
Posts: 2,429
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From: Minnesota
READ and or search..
< google > why 85 octane in the mountains.
here is 2
https://tap.fremontmotors.com/truste...se-at-altitude
https://www.quora.com/Why-is-regular...ion-U-S-states
< google > why 85 octane in the mountains.
here is 2
https://tap.fremontmotors.com/truste...se-at-altitude
https://www.quora.com/Why-is-regular...ion-U-S-states
Is 85 Octane Ok To Use At Altitude?
It seems there is not a definitive answer to this as far as modern vehicles go (anything without a carburetor).The EPA says on their website, “The sale of 85 octane fuel was originally allowed in high-elevation regions—where the barometric pressure is lower—because it was cheaper and because most carbureted engines tolerated it fairly well. This is not true for modern gasoline engines. So, unless you have an older vehicle with a carbureted engine, you should use the manufacturer-recommended fuel for your vehicle, even where 85 octane fuel is available”.
85 Octane is old school . . . . Ford says never use less than 87 octane.
Laughing Gas
Joined: Oct 2017
Posts: 922
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And using information out of the link you provided . . .
The EPA says on their website, “The sale of 85 octane fuel was originally allowed in high-elevation regions—where the barometric pressure is lower—because it was cheaper and because most carbureted engines tolerated it fairly well. This is not true for modern gasoline engines. So, unless you have an older vehicle with a carbureted engine, you should use the manufacturer-recommended fuel for your vehicle, even where 85 octane fuel is available”.
85 Octane is old school . . . . Ford says never use less than 87 octane.
Is 85 Octane Ok To Use At Altitude?
It seems there is not a definitive answer to this as far as modern vehicles go (anything without a carburetor).The EPA says on their website, “The sale of 85 octane fuel was originally allowed in high-elevation regions—where the barometric pressure is lower—because it was cheaper and because most carbureted engines tolerated it fairly well. This is not true for modern gasoline engines. So, unless you have an older vehicle with a carbureted engine, you should use the manufacturer-recommended fuel for your vehicle, even where 85 octane fuel is available”.
85 Octane is old school . . . . Ford says never use less than 87 octane.
Logistics Pro
Joined: Apr 2000
Posts: 4,334
Likes: 306
From: Mills River
Modern engines will likely retard ignition timing to compensate for low AKI fuel, and the engine will probably appear to operate without issue. However, power and fuel economy will likely suffer.
HTH,
Jim / crewzer
HTH,
Jim / crewzer
Laughing Gas
Joined: Oct 2017
Posts: 922
Likes: 7
I'm sure they do, on top of the hit for the altitude. Used to drive s stick shift na car. Absolute dog at this altitude. Now have a turbocharged car which is night and day.