Why is Colorado, NM and Amarillo gas only 85/86 Octane?

[SDET]

I'm afraid to put that in my tank and pay for the mid-grade. Most "regular unleaded" around the country is 87 Octane.

 

[eohrnberger]

I'm afraid to put that in my tank and pay for the mid-grade. Most "regular unleaded" around the country is 87 Octane.

I don't know the answer to that question, but I'm interested in the answer.

I know that there is a summer blend and a winter blend of gas here in Michigan and I believe that it has to do with the amount of smog that's generated during the different months of the year's prevalent temperatures.

Perhaps something to related to that?

 

[EMNofSeattle]

I'm afraid to put that in my tank and pay for the mid-grade. Most "regular unleaded" around the country is 87 Octane.

Because the lower air pressure at high altitude has the effect of lowering the compression ratio in your engine, hence 85 will burn like 87 above 6000 feet. Hence Colorado, parts of Utah and the like at high altitude can sell 85.

I don't know if Amarillo Tex is at high altitude, but this is the reason gas is lower in Colorado, and parts of the Great Basin.

If you'll be doing a lot of local driving in that area you can use 85, if you are just passing through and will be back soon at lower alt the use 87.

 

[dimensionallava]

it depends on your engines compression ratio but if you want to stay on the safe side, always buy the expensive stuff they sell 85/86 octane gas in the mountains because at higher elevation theres no need for high octane gas, so its okay to use the cheaper 85 octane

 

[Lord Tammerlain]

it depends on your engines compression ratio but if you want to stay on the safe side, always buy the expensive stuff they sell 85/86 octane gas in the mountains because at higher elevation theres no need for high octane gas, so its okay to use the cheaper 85 octane

If the car is turbocharged, you will want to use the higher octane gas (if the engine calls for it) as it will have higher compression then NA engines at high altitudes

 

[JumpinJack]

I'm afraid to put that in my tank and pay for the mid-grade. Most "regular unleaded" around the country is 87 Octane.

Altitude? Altitude in winter?

 

[SDET]

Because the lower air pressure at high altitude has the effect of lowering the compression ratio in your engine, hence 85 will burn like 87 above 6000 feet. Hence Colorado, parts of Utah and the like at high altitude can sell 85.

I don't know if Amarillo Tex is at high altitude, but this is the reason gas is lower in Colorado, and parts of the Great Basin.

If you'll be doing a lot of local driving in that area you can use 85, if you are just passing through and will be back soon at lower alt the use 87.

I drove to Colorado to get a new vehicle with Kinetic suspension which isn't marketed here in Texas. It was cringeworthy that they included a "free tank of gas". It's "cute" that Denver charges more for 85 octane than Dallas charges for 87 octane for which I recently filled up on for $1.399 .

 

[EMNofSeattle]

I drove to Colorado to get a new vehicle with Kinetic suspension which isn't marketed here in Texas. It was cringeworthy that they included a "free tank of gas". It's "cute" that Denver charges more for 85 octane than Dallas charges for 87 octane for which I recently filled up on for $1.399 .

Market conditions require higher gas prices in Colorado then Texas.

Do not cringe, you can use the 85 gas just fine. a trip or two to Tex on 85 won't hurt your engine, I've filled up on 85 fuel before in Montana and drove to Spokane on it.

 

[poweRob]

Because the lower air pressure at high altitude has the effect of lowering the compression ratio in your engine, hence 85 will burn like 87 above 6000 feet. Hence Colorado, parts of Utah and the like at high altitude can sell 85.

I don't know if Amarillo Tex is at high altitude, but this is the reason gas is lower in Colorado, and parts of the Great Basin.

If you'll be doing a lot of local driving in that area you can use 85, if you are just passing through and will be back soon at lower alt the use 87.

Check out the big brain on EMN!