niterydr
12-12-2007, 09:33 AM
I thought I was going nuts out here at WyoTech. I get about 20% less fuel economy in this cold out here!! And I'm at like ~7500ft. about too if that matters with gas consumption.
More air(denser and lower elevation and cold) = more fuel to get A/R
Less Air and Less Dense+Freezing Air = opposite?
I dunno.
Air and fuel molecules need to find matching dancing partners. If you have 1470 air molecules and 100 fuel molecules, then you have a 14.7:1 afr.
If you have a more dense air charge, aka 2940 air molecules, you need 200 fuel molecules to get that 14.7:1 ratio.
Make sence?
Colder air is more dense=more air molecules.
Its why inefficent turbo setups can "overboost" in cold weather and heat soak/have boost fade in hot summer months, they are getting more air molecules and are at an advantage on the compressor side of things and that carries thru the system to the engine. Most of the time engine bay temperatures balance out after the car is up to operating temperatures, but a car WILL make more boost @ 0 degrees versus 100 degee intake air temperatures if the system isn't setup/tuned properly to avoid that.
More air(denser and lower elevation and cold) = more fuel to get A/R
Less Air and Less Dense+Freezing Air = opposite?
I dunno.
Air and fuel molecules need to find matching dancing partners. If you have 1470 air molecules and 100 fuel molecules, then you have a 14.7:1 afr.
If you have a more dense air charge, aka 2940 air molecules, you need 200 fuel molecules to get that 14.7:1 ratio.
Make sence?
Colder air is more dense=more air molecules.
Its why inefficent turbo setups can "overboost" in cold weather and heat soak/have boost fade in hot summer months, they are getting more air molecules and are at an advantage on the compressor side of things and that carries thru the system to the engine. Most of the time engine bay temperatures balance out after the car is up to operating temperatures, but a car WILL make more boost @ 0 degrees versus 100 degee intake air temperatures if the system isn't setup/tuned properly to avoid that.