All that variety of scenery (and generally mild weather) is why the film industry became established in California. Originally most of the studios were in New York, but filming outdoors was difficult there and the scenery has less variety. There are plenty of places within a few miles of LA that are perfect for filming a western. Or a Bible epic. The beginning of Murder She Wrote was filmed in Mendocino, not Maine.
@JoeMario ā¦I have made this ātripā 30 times over the past ~10 years. Wind direction will have an effect depending on which direction Iām going, but there is always a +2-3 mpg difference while in driving at the higher altitudes or in the mountains states, no matter whether Iām coming or going. And, while driving on the interstate highwaysā¦they are sometimes mountainous (southern CO & northern NM)ā¦but, for the most part they are flat to rolling. Iām thinking that the reduced or lack of āethanolā in the mtn states may be the difference. I will look at the fuel pumps in CO & WY next time and see if they say āminimum of 10% ethanolā like they do in TX and OK.
Thanks for your expert opinion!
@jasmith5 ā¦I really donāt understand why itās so hard to accept the possibility that the high altitude itself is responsible for the increased gas mileage.
Consider the fact that on a typical car cruising at highway speeds, about 30% of the power produced by the engine is consumed by tire rolling friction, about 15% is consumed by drivetrain losses, and the rest, about 60% of the engineās power is consumed by air resistance.
At sea level, a cubic yard of air weighs about two pounds, most people are surprised that air actually weighs that much.
At 5000 ft above sea level, a cubic yard of air only weighs 1.67 pounds or about 83.5% as much as sea level air.
Since the air at 5000 ft is only 83.5% as dense as sea level air, the air drag at a given speed is only 83.5% that of sea level air drag.
When you consider that the most of the engineās power is used to push air out of the carās way at highway speeds, it makes perfect sense that you get better gas mileage at high altitudes.
I would even wager that a Tesla electric car would have a longer range if driven at high altitudes.
Have a pretty good sample size to show that the OP is correct in that vehicles absolutely get better milliage in Rockies than at least the east coast. My company recently relocated several hundred of us from the Rockies to Virginia. Some of us drive out here and other flew and had their vehicles shipped. I have 3 different vehicles of different makes but all with digital gas milage readouts. The one we drove out here now gets 5 mpg less. From 27mpg to 22.
My other 2 were shipped so no driving between states. Got 26 mpg on my CRV now getting 23mpg.
Got 18 mpg on my Tacoma out west now getting 14mpg.
Spoke to other transfers. Can confirm that at least 93 different persons have noted a significant loss in gas milage from out west to here in Virginia.
So itās not just an octane thing or a miscalculation thing. The vehicles are legitimately getting less mpg on Virginia than Colorado or Utah.
Golf balls definitely donāt fly as far in Calif compared to Colorado. Especially at courses near the ocean, the Calif golf ball acts like it is traveling through extra heavy air. 20 yards difference, easily.
Excuses, excuses, excuses. 
We went to Maine from Ohio end of May.
In OH a full thank a little over 300 mi.
I had a shock at the first full thank in Maine. I had to check it several times to believe it. 500 mi.!!!
I need a real explanation on it if you can.
(GMC Arcadia 3.6 L, 2015)
Sometimes wind can make a big difference like that.
The ratio of oxygen to nitrogen is nearly constant at all altitudes. Airliners cruising at 40,000 feet simply have to pump in air to keep the cabin pressure at around 11psia, they donāt have to add supplemental oxygen. They donāt have to heat the air either. Simply compressing it to 11 psi raises its temperature from minus 40 to a comfortable for humans temperature.
Iād expect the contrary, maybe somewhat fewer miles on a tank in Maine, b/c it is colder in Maine than Ohio. My guess, the number of gallons in a ātankā varies, depends on the characteristics of the fuel pump where you buy gas , your carās evap system configuration at the time you purchase gas, and how much fuel remains in the tank when your decide it is close to empty.
If you are really experiencing widely varying mpg, one common reason is a faulty coolant temp sensor.
Hi B.L.E.:
Weāre in full agreement on the āratioā of oxygen to nitrogen at all altutides.
My wording could have been a bit clearer. I was referring to the lower air pressure at higher altitudes causing each intake stroke to result in less oxygen, as well as less nitrogen.
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In that case, how does the combustion chamber know the difference between 5psia manifold pressure due to a partially open throttle and 5psia manifold pressure due to high altitude. Assuming the same fuel/air ratio and spark timing.
The old mechanical distributers would under-advance the spark because the vacuum advance had less atmospheric pressure on the ambient pressure side of the diaphragm. I guess that could have been solved with a pressurized distributor but I think that modern EFI goes by either absolute manifold pressure or mass flow sensor readings.
Did you know that high altitude bombers of WWII actually did have pressurized magnetos? This was done to prevent flashovers at high altitude. The lower the air pressure, the more easily the air ionizes.
I dunno but back in the carb days folks used to talk about readjusting the carb if youād spend much time in the mountains. I remember grandma having trouble boiling water for coffee in the mountains. I thought it was interesting but was only ten and didnāt drink coffee yet. I guess filed under the heading of people need to get out more.
Water boils at a lower temperature at lower pressure (higher altitude), so the water boiled, it just wasnāt hot enough.
Carbs were poor at adjusting for the lower air density, so they ran rich (I think, maybe it was lean) at higher altitudes. Not a problem with fuel injection. But max power is down, even with FI, unless a turbo is used.
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Back in the carb days, the only adjustment for high altitude available on most carbs was the idle circuit. The main jet, which was used anytime above idle, had a fixed diameter opening that preset the amount of fuel passing through it.
Some carbs had a needle that got raised and lowered into the main jet, and the needle height could be adjusted.
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It turns out that a (very) few carbs has an āaltitude compensatorā that leaned out the mixture at high elevations. Hereās a little info on the one in a Motorcraft 2150:
2150 High Altitude Compensator - Mikes Carburetor Parts (carburetor-blog.com)
I couldnāt remember rich or lean. Guess altitude makes it run rich so ya lean it out. I would have gone the other way. Reminds me of my 74 olds that had those plastic limiter caps so you couldnāt richen it too much.
Coffee experts say that brewing coffee at about 200F produces the best coffee since it doesnāt extract bitter oils like 212F coffee would. Water boils at 200F at about 6500 ft above sea level. Even at 10,000 ft water boils at 190F. Youād have to be way up there to make coffee brewing impossible.
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Iām not a coffee drinker, but several years ago I was listening to NPR and they had this coffee expert on. He was telling how to brew the perfect cut of coffee. He said to boil water to 191.7 degrees (or some stupid number like that). Said that even being off by .2 degrees can affect the taste. Seemed like way too much effort to me.
I was just explaining grannyās complaint about making coffee. The water wasnāt hot enough for her, I guess I should have said. Of course people make coffee in Denver, etc.
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