Loss of power at high altitude.

[snowmobile]

I've been for a drive acouple of times up Perisher and have noticed that my vn seems a bit sluggiish while im on the mountain (the flat parts).I'm wondering if it's to do with the altitude which is about 1700 m to 1850 m ,maybe the computer does'nt register that it's up at that hight?

[Boonz]

any car at that height would run like crap cos there isnt enough oxygen.....look what happened to the dude who climbed mount everest.....run out of oxygen brain works shit ......run a car out of oxygen motor runs shit

[pandaman]

any car at that height would run like crap cos there isnt enough oxygen.....look what happened to the dude who climbed mount everest.....run out of oxygen brain works shit ......run a car out of oxygen motor runs shit

1700 metres ASL aint exactly everest. Might have an effect though. Any significant change in atmospheric pressure will freak out your MAP sensor a bit i think. Might be worth doing a bit of research on how it's affected. I'm too lazy as per usual.

[foammedia]

My VN had a VERY noticable loss in power just in the Adeliade hills, it makes a big difference. I lived in a town in Mexico at 2200 meters and that was on the valley floor!. One day I went for a run and made it about 400 meters before I was nearly dead and I should at sea level be able to run 5ks with less effort than that 400 meters, it does the same thing to cars and is the most important reason for owning a turbo

I've attached a photo of VN V6 power loss at 1850 meters, the red power line and aqua torque line are the sea level ones

[mouce]

It's really noticable even just driving around Falls Creek, the air pressure is WAY lower, and yeah...it has a big drop in power. Idle is really dodgy too, typically idle sits at about 19"Hg on the vac gauge around Melbourne, up at Falls Creek idle is down at about 10"Hg, that's a huge drop.

For anyone who doesn't understand the significance of that: the level of vac pressure corresponds inversely to the amount of throttle (or IACV) the engine requires to run, a large vac figure means that there's not a tonne of air getting through to the engine and it's all happy. A small vac figure shows that it needs to open up the IACV a little more to keep it at the same engine speed.

[fazz1977]

air at higher altitude is less dense than at lower altitude. The denser the air, the better fuel and air mix and combust. Simple physics and chemistry.

[pandaman]

air at higher altitude is less dense than at lower altitude. The denser the air, the better fuel and air mix and combust. Simple physics and chemistry.

True, but I just didn't think a few hundred odd metres would make would make that much of a difference. Ahh well, learn something new everyday.

[IBLOWN]

i also notice this in mine. hammers at sea level, but when i went to bathurst it went like an absolute dog! i couldnt believe the power loss, plus i had no boost when at the time it was running 3-4 psi.

[snowmobile]