85 octane question

[Scubawise]

We just traveled thru WY NE CO and see 85 for 15 to 30 cents less per gallon

Can this be used in our Ford engine vegas?

[ducksface]

It's fine.
We have 85, 89, 91 as our only options here. No 87, no 93.
My 26,000 miles have been on 85 octane.

[Chateau_Nomad]

My motto is if it will run on lawnmower gas... use it!

[Bob Denman]

If it can burn: your engine can burn it...

... but it will probably not give you the best performance.

[Scubawise]

Thanks all

[abjbrtd]

Originally Posted by Scubawise

We just traveled thru WY NE CO and see 85 for 15 to 30 cents less per gallon

Can this be used in our Ford engine vegas?

I'm pretty sure the Ford V10 is not a flex-fuel motor!

Check your owners manual BEFORE filling with E85.
If you've already filled you should use it asap, with frequent stops for a few gallons of E10, E0 if you can find it would be better

Edit: 85 is not the octane rating it's the % of ethanol, not good!

[Chateau_Nomad]

It's printed on the gas cap on mine... Without going out and looking I believe it's 10%. Most gas in Ohio is "may contain up to 10% ethanol". But you can buy "racing fuel" at most Sunoco stations with no ethanol... expensive though.

The extra octane is a waste of money IF your engine doesn't require it. Some people claim it runs better, but the science says otherwise. Use what your manual recommends. Higher octane is a waste... lower octane can cause knocking which could do damage long term.

[16ACE27]

Originally Posted by abjbrtd

I'm pretty sure the Ford V10 is not a flex-fuel motor!

Check your owners manual BEFORE filling with E85.
If you've already filled you should use it asap, with frequent stops for a few gallons of E10, E0 if you can find it would be better

Edit: 85 is not the octane rating it's the % of ethanol, not good!

The discussion is regarding the lower OCTANE gas available at higher altitudes, not ethanol content. It's best not to conflate the two.

[Lt Keefer]

Most modern engines are designed to run on fuel with an octane rating of 87. Sure, it will run on 85 but you will be getting less performance, poorer fuel mileage and decreased engine life. That info is all contained in the owners manual. If you are talking about E85, it will kill your engine unless you have a flex fuel motor.

[Scubawise]

Thx saw this
Your engine is designed to run on 87 octane at sea level. It will run just fine at 4000 ft and above on 85 octane. With lower air pressure comes lower combustion chamber pressure and reduced chance of ping. Don't waste your money on octane you don't need.Jan 28, 2018

[airforceret]

Because the air is less dense, less air flows to your car's engine. This translates to a slightly richer air-fuel ratio, and deters engine knock. For that reason, you'll find that regular gas carries an 85 octane rating here in Denver and throughout Colorado, Wyoming, Utah and Montana.

[dkoldman]

This is where you can simply ignore the science in favor of the math $.20 - $.30 cents / gallon of gas is cheaper; so buy it


This video is why I may never go Glamping in Montana

https://missoulian.com/grizzly-bear-...dfadb4dfe.html

[Beau388]

Originally Posted by airforceret

Because the air is less dense, less air flows to your car's engine. This translates to a slightly richer air-fuel ratio, and deters engine knock. For that reason, you'll find that regular gas carries an 85 octane rating here in Denver and throughout Colorado, Wyoming, Utah and Montana.

True the air is less dense, but your engine has a one bar Manifold Air Pressure (MAP) sensor and an Initial Air Temperature (IAT) sensor that allows the Engine Computer Unit (ECU) accurately determine the actual air density and inject the correct amount of fuel for the computed density. The feedback from the three O2 sensors ensures the fuel air ratio is correct. The reason that 85 octane rated fuel is available is the air density effectively lowers the compression ratio sufficiently to allow the engine to run successfully at altitudes 4,000 ft ASL.

[Scubawise]

Originally Posted by Beau388

True the air is less dense, but your engine has a one bar Manifold Air Pressure (MAP) sensor and an Initial Air Temperature (IAT) sensor that allows the Engine Computer Unit (ECU) accurately determine the actual air density and inject the correct amount of fuel for the computed density. The feedback from the three O2 sensors ensures the fuel air ratio is correct. The reason that 85 octane rated fuel is available is the air density effectively lowers the compression ratio sufficiently to allow the engine to run successfully at altitudes 4,000 ft ASL.

Does that mean whenever 85 is available we can use?

[Bob Denman]

Originally Posted by dkoldman

This is where you can simply ignore the science in favor of the math $.20 - $.30 cents / gallon of gas is cheaper; so buy it


This video is why I may never go Glamping in Montana

https://missoulian.com/grizzly-bear-...dfadb4dfe.html

Haven't we had enough of "ignoring the science"?

[Scubawise]

Originally Posted by Bob Denman

Haven't we had enough of "ignoring the science"?

Oh no stop. Stop montana is excellent..go camping..even KOA has bears ..just call our bear holiness. They will send an F15. JOKING

[Chateau_Nomad]

Originally Posted by Bob Denman

Haven't we had enough of "ignoring the science"?

You're probably thinking of "alternative facts".

But on the octane, there should be a section/chart in the owners manual detailing type of fuels to be used in the engine - similar to the way they explain oil specs for different climate/conditions.

[Bob Denman]

... And there was!

[Beau388]

Originally Posted by Scubawise

Does that mean whenever 85 is available we can use?

Yes if you are consistently above 4,00 ft above sea level. Should you descend below that elevation, you should use 87 octane gasoline. It works about the same as the cold air pressure in your tires. As you go up in elevation the outside air pressure decreases so the air pressure in your tires will increase. The reverse is true when you descend in elevation.
Most modern gasoline engines have knock sensors to prevent damage if fueled with a lower octane fuel than is recommended. The Ford V-10 does not use knock sensors, so it up to the owner to use the proper fuel.

[ducksface]

About alternative facts:

The sky is not blue
The sun does not set in the West
Walnuts are not nuts.

Name some others.