Can anyone explain why a 2300 RPM power setting gives a different power % at different altitudes??

Answer 1

Yep,.............at an average altitude of 600 ft., 2300rpm lets say in thrid gear will allow and engine to perform to allow you to drive at a certain speed and lets say that speed is 60kpm since you guys are metric,........well at a higher altitude and we'll say that new altitude is 4500 ft. then in 3d gear, the kpm will be slower because the engine is struggling to breathe alot more air that isnt there at 4500 ft. compared to what's there at 600 ft............now,.....so you change to 4th gear to lower the gear ratio and the engine then bogs down cuz of the wieght of the vehicle,.........it's a balance of power compared to how much available oxygen there is in the air at differing altitudes..................Here for instance we are not metric but standard,........I live at the 360 foot mark on the edge of the inside of a volcano spillway,......just a few miles east of me is the calapooya range of mountains where I hunt for gems and for mushrooms and for gold,.......I go from here to the base of the mountains at the altitude of 890 feet,.....I go from there to 4500 feet to the top of one mountain and at 1800 feet I immediately notice a difference in the power I get out of my engine,......Now at 2000 feet, there is a line where the snow begins to start when it gets cold, at 2500 feet the snow gets deep when it's cold, at 2000 feet it's a foot or so, at 2500 feet it's 4 feet deep, at the top it can be 8 to 10 feet deep or none at all because the clouds can be just thick enough to where the snow that falls happens between 2000 feet and 3750 feet.......the air above that is so thin that it is hard to breathe and an engine can simply stop or just not run if the wind is blowing at all because the main part of the oxygen is tied up in water vapor which is now frozen,......no oxygen? just fuel?.......no ignition!..you could dowse yourself in petrol and try and light yourself on fire and you'd just be covered in petrol, not that you'd wanna do that....ok so now it's a "no go", now you walk! long way down, long way home, awful cold.......does that explain anything? cuz I know I can be awfully abstract.

Answer 2

A 2300 RPM power setting gives a different power percentage at different altitudes because the air is less dense at higher altitudes.

Answer 3

Unless you've got a controllable pitch prop, or
supercharger to regulate manifold pressure
the density altitude will determine the power
available at any given RPM condition.
The higher you go, the thinner the air,
the lower the available power.

Answer 4

The density of the atmosphere drops with altitude. The drop in density means you get Less air per unit volume the higher you go. Less air for the same volume means les oxygen for combustion. this this is why aircraft were limited in altitude until the invention of the turbocharger which compresses the air fed to the engine.

Answer 5

Power is related to the density of air. The more dense air is the more air it can compress with fuel to combust to make power. As a airplane climbs, the air becomes less dense, so therefore creates less power. To overcome this loss of power, most high performance aiplanes use a turbocharger to pressurize the air in the intake to make it more dense at high altitudes.

Answer 6

Air density decreases with altitude.

Answer 7

Air Density is different at different Altitudes. The Props can get the same amount of "bite", jets cannot get the same amount of compression.

Answer 8

density of the air that the propeller is grabbing is different at different altitudes..

Think of a boats prop turning in something thick like oatmeal or something thin like whipped cream.

Answer 9

It's all in the density altitude...and the old suck, squeeze, bang, blow.....

Less dense atmosphere ...less oxygen..less suck, squeeze, bang, blow with every stroke...

Is this as exciting to read as it was to write?

Answer 10

Amount of oxygen lessen at higher altitudes.