Elevation and MPG

OP, Get a ScangaugeII. I live in Albuquerque, NM (5500' ASL). I gained 3-4 MPG by seeing realtime gas comsumption and changing my driving style. I have BFG LT265/75/R16.

I drive into the mountains to Santa Fe daily. Average 20-22 MPG.

http://www.fuelly.com/driver/wile/tacoma

 

You apparently don't understand.

So what if the percent of oxygen is the same at 100,000 ft as at ground level? There is actually less oxygen available, in fact almost none. That it can be said to be because of lower partial pressure is true but doesn't change the fact that there is less oxygen molecules per volume of atmosphere which is the point.

You were short of breath because of less oxygen, no matter how you spin it.

Looking at it in reverse, there is less partial pressure because there is less oxygen and all the other gases at that altitude and above.

http://www.altitude.org/air_pressure.php

At 6000ft, the standard barometric pressure is 82kPa (617 mmHg). This means that there is 81% of the oxygen available at sea level.


That means less oxygen.

 

Most likely a different in the terrain that is causing the poor mpg at the higher elevation. Manual or stick? Keep it floored on every incline?

On the front range you have relatively flat travel which is good for mpg. That you say betwen 9-12k on a daily basis means you do lots of climbing which has already been pointed out as bad for mpg.

The fact is that if you could somehow find a relatively flat travel at 12K you would get better mpg than at 5K.

I don't doubt you get worse with your commute than in Denver, but it's for other reasons than the altitude factor.

 

Another reason, since a 2.7L engine would behave like a 2.2L engine a mile up airflow-wise, there will be less manifold vacuum for any given power output and much less pumping losses. Definitely better for mpg, then you get to add lower air resistance to that. Sounds like skierdude's compensating for power loss in the thin air by going open loop a lot more without realizing it and burning all his daylight oil.

 

Good points iroh.

 

You're as dense as a fart in Death Valley... the point I was trying to make is about the density of O2 at varying
elevations, not that there is somehow less O2 for any other reason.

 

i do have a scanguage

 

It just seems as though my car always tries harder at higher altitude.....when I had a 4cyl up here it sputtered to pass cars......

I think my point is even if better mileage can be achieve at higher altitude 9k ft+, it always comes withs hills and constant elevation change which more than counteract the mpg savings...make sense???? so the savings is moot?!?!

 

Then why are we having this discussion