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Author Topic:   Weather and Horsepower?
RangeRover
Member
posted October 29, 2004 09:27 AM
Humidity **the amount of moisture in the air** and Barometer **the density of the air** plays a big roll along with temps. There are charts out there that show the effects of Air fuel ratio per humidity, barometric pressure, and temp.



Bluebomber
Member
posted October 29, 2004 02:27 PM
I am no expert on this subject but here are a few thoughts:

humidity-- water vapor displacing oxygen in the air charge; also effect the rate at which the air charge would take on heat (slower)

bar. press. -- at higher press. the air is denser requiring richer jetting just like running at a lower altitude

fuelcar302
Member
posted October 30, 2004 10:45 AM
quote:
Originally posted by Bluebomber:
I am no expert on this subject but here are a few thoughts:

humidity-- water vapor displacing oxygen in the air charge; also effect the rate at which the air charge would take on heat (slower)

bar. press. -- at higher press. the air is denser requiring richer jetting just like running at a lower altitude



Bluebomber is correct on this info . For all you normally asperated dirt guys . You need to have some type of weather station that will give you a corrected altitude. That consists of baro, air temp, humidity, and the most importantly grains . I've tuned nitro fuel car & boats for 20yr. in order to satisfy air -fuel mixtures correctly you need to know how much oxygen is available in 1 cubic foot of air . The more the grains the less oxygen.


Bluebomber
Member
posted November 01, 2004 06:32 AM
that's what being a science teacher and a racer get for youi --- lol