[WhiteMale]

91 or 93 shouldn't be a real appreciable difference, but 87...ya that's sure to have pulled all the timing out of it if that's indeed 87 octane.

[Ventmaster]

And heaven forbid if they sell 85 octane in your part of Oklahoma. Here in S.Utah they do sell 85 everywhere on the pretense that so many folks are on their way to Salt Lake City at over 6,000 ft above sea level. It saves you 10 cents on the gallon. Therefore, most people just run 85 even though we're at 3K elevation and their vehicles call for at least 87 octane. 91 octane is the best they can do around here at considerably more$. E-85 is available- in Las Vegas.

[Green82]

[QUOTE=Ventmaster;11483082]And heaven forbid if they sell 85 octane in your part of Oklahoma. Here in S.Utah they do sell 85 everywhere on the pretense that so many folks are on their way to Salt Lake City at over 6,000 ft above sea level. It saves you 10 cents on the gallon. Therefore, most people just run 85 even though we're at 3K elevation and their vehicles call for at least 87 octane. 91 octane is the best they can do around here at considerably more$. E-85 is available- in Las Vegas.[/
87 is the lowest i have seen highest in my area is 91
closest place for e85 is 80 miles away

[GreyGhost702]

Originally Posted by Ventmaster

And heaven forbid if they sell 85 octane in your part of Oklahoma. Here in S.Utah they do sell 85 everywhere on the pretense that so many folks are on their way to Salt Lake City at over 6,000 ft above sea level. It saves you 10 cents on the gallon. Therefore, most people just run 85 even though we're at 3K elevation and their vehicles call for at least 87 octane. 91 octane is the best they can do around here at considerably more$. E-85 is available- in Las Vegas.

Truth.

I'm at 5,000ft average and I see everything from Audi's to Ecoboosts pumping that 85 octane trash. To a degree, I get it. It's the cheapest button at the pump by far. When 85 is $3.00/gal and 91 is $3.80 it's a real pill. Particularly since no one wants to drive wages up with inflation, everybody keeps taking a pay cut as inflation freight trains the devaluation of the dollar. The worst part, the local agencies push the whole "higher elevation" fallacy down the publics throat as an excuse to keep producing this trash. The public never fights back, most don't know any better, a lot of folks can barely afford to put spit in the tank let alone proper octane fuel. As far as E-85, there is 1 station in Ogden, UT that I'm aware of that sells it. There is a private "dealer" or performance shop in the Salt Lake valley that sells E-85 Race Fuel, but this isn't the shit you get to pump for $.50 under Regular. It's race gas prices, so while he's popular to the race crowd and well-to-do enthusiasts, not exactly a practical option.

Pretty much anything built after 1990 that's fuel injected should be running minimum 87 octane, REGARDLESS of elevation. The computer will compensate AFR and timing all on its own. 85 Octane will do nothing but get you worse fuel economy so the cost savings at the pump is nothing but a feel good while you pump it, you'll just be back to the pump sooner. I would say everything after 2015+ and especially anything FI, needs to be running 91 regardless of elevation. Post 2015 you have more DI engines than ever before, running higher compressions, and more factory FI engines than ever before. I don't even know what manufacturer produces a vehicle that has it in its owners manual that states it's acceptable to run anything less than 87 octane since the 90's.

The powers that be are fully aware, but as long as there is no demand from the public there'll be no change. And thanks to knock sensors and smarter technology, people aren't inclined to pump proper octane even if they could afford it.