87 octane

[CLIFFTALL]

I'm in New Mexico and have fueled up twice. The octane offering are 86 or 88. I thought it best to use the 88 even though it costs more. I just did a search in this Ford Forum and this was discussed in 2009. Ford states that we shouldn't use anything less than 87



I know there will be a lot of opinions and testimonials on results with lower octane.
I choose to go with Fords advice.

Just thought I'd post this for those traveling in high altitudes.

[jimbo16720]

Next time you fuel up read the small print on the pump and most say 10-15% ethanol added. It's hard to find a station that sells straight gasoline anymore. What they don't tell you is that's why you have to add Stabil or some other additive to your gas if you don't use it right away. Plus it's not made for older vehicles and eats rubber seals and hoses and collects rust in your gas because it absorbs water. So even though it say 87 octane don't believe it.

[CLIFFTALL]

That's a separate subject. Since you brought it up , Ford says not to use any ethanol higher than 10%.

[Neumann]

Oh great.
I guess I never really looked at the numbers on the gas pump. Always just pump the low octane stuff. Don't think I ever looked at the ethanol numbers.
When we need gas we need gas. Most times don't have a selection of gas stations to stop at.
Now I will look but not sure what to do when I need a fill up in the middle of no where.
since my hair is white now I guess I'll just start losing it.
Hal

[ShadowT]

In traveling across the country last year (Fl to Wa), my V10 ford liked mid-grade best with an MPG of at least 1 MPG greater than regular low grade with mid grade.

[LVJ58]

Hi Hal,

In our travels, we've also run into those areas where there's no 87 octane, just 85 or 89 & higher. I usually go with the mid grade 89 or so rather than the 85. Sure, it costs a bit more, but I'd rather play safe when it comes to my engine.

So how's that new engine holding up??

Happy Trails,

Jim

[jimbo16720]

Originally Posted by Neumann

Oh great.
I guess I never really looked at the numbers on the gas pump. Always just pump the low octane stuff. Don't think I ever looked at the ethanol numbers.
When we need gas we need gas. Most times don't have a selection of gas stations to stop at.
Now I will look but not sure what to do when I need a fill up in the middle of no where.
since my hair is white now I guess I'll just start losing it.
Hal

Trust me it's in real small print on a sticker on the pump. It should say at least 10% ethanol. I know some states have a law that says they have to post it on the pump and some don't. I actually seen on the news the other day a station in Penna. down by York that still sells gas without ethanol.

[wirelessenab]

Originally Posted by jimbo16720

Next time you fuel up read the small print on the pump and most say 10-15% ethanol added. It's hard to find a station that sells straight gasoline anymore. What they don't tell you is that's why you have to add Stabil or some other additive to your gas if you don't use it right away. Plus it's not made for older vehicles and eats rubber seals and hoses and collects rust in your gas because it absorbs water. So even though it say 87 octane don't believe it.

What don't you believe? The octane of gasoline? For what it is worth ethanol is close to 110 octane. If the gasoline supplier doesn't mess with the gasoline in any other way, then the more ethanol, the higher the octane of the fuel.

Also at high altitude your engine can use lower octane without detonation, harming itself, because there is less oxygen at higher altitudes.

[subford]

Originally Posted by wirelessenab

Also at high altitude your engine can use lower octane without detonation, harming itself, because there is less oxygen at higher altitudes.

This maybe true if you have a carburetor on the engine but not true with fuel injected engines.
The oxygen in one cu ft of air is the same proportionally to the other gases at higher altitudes. There is just less of all the gases at higher altitudes as the air is thinner at higher altitudes.
The computer will change the amount of fuel going into the engine to companstate for the less oxygen.
So the end result is the same and you need the same octane at higher altitudes.

[Neumann]

I guess I'm not going to worry about the octane rating. Maybe I'll try a higher number and see if I get better mileage.
I have about 3,000 miles on my new V-10 engine and getting 6.3 MPG now. Runs great. Seems to have more power than the old engine as it goes up hills faster.
Changing the oil this week to get ready for a long summer trip.
Hal

[C-Leigh Racing]

To bring it into perspective, like if you drink mixed drinks, & I'm not saying anybody on here drinks, but do you want a straight drink from the bottle, full strength, or one the bartender has watered down but cost the same amount as the straight one.

I look at the octane gas I use, dependent on what the engine has to do, how big & hard of a job it has.
Like in the colder months where the engine not under so much heat, I'll probably use the 87 octane because the engines not working as hard from the lower outside temps.
Now in the real hot summer time, when the radiators trying its best to keep the engine cool to a normal operating temp, I'll use a higher octane gas to help keep the pistons & heads a bit cooler.
The flash point of the gas what you need to think about most.
The 87 octane has a faster burn rate than say + 89 or 92 octane, & in the hot summer time because the engine will be running higher temps it will cause the burn rate to be even faster.
The load your m/h engine is trying to move, something you need to look at as well. Like if you only have the m/h itself weight, then you could probably get by with using 87 octane all the time, but put the toad behind, then that m/h has a bigger job to do, more strain on the engine.
Most of you, probably dont have as big of a load to move as I do, then theres some of you that do. Every time we pull out of our driveway, we are over 25,000 lbs & working that V10 hard, so I'll use the 89 & sometimes 93 octane gas in an attempt to keep those pistons & heads cool.
Neil

[Mekanic]

The 86 octance isn't nearly as bad as you might think. If you buy 20 gallons of each the 86 and the 88 you will have added 40 gallons of 87 octane.
The reason for the lower octane is that at higher elavations your engine doesn'trequire as much anti knock be cause the the thinner air lowers the effective compression of the engine.

[Fiesta48]

I have a ScanGuage II. The winter and summer, coolant and cylinder head temps are always within 5 degrees. I doubt using mid-grade or premium will make any difference. (Except in your wallet.) I do agree 86-87 octane burns faster than higher octanes. Therefore should get better MPG or power than higher octane, unless the timing is being retarded. Then higher octanes will improve power/MPG.

[Mr_D]

Originally Posted by wirelessenab

Also at high altitude your engine can use lower octane without detonation, harming itself, because there is less oxygen at higher altitudes.

Exactly what Banks and some of the engine builders as well as the car maufacturers say too.

Also, Popular Mechanics says the same thing here