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Cold air vs warm air

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Old Jul 27, 2005 | 03:10 PM
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Default Cold air vs warm air

I can't figure out why cars get better mileage in summer than in winter...shouldn't cold air be denser and therefore better for combustion and mileage?

Anyone know?
Old Jul 27, 2005 | 03:18 PM
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Default RE: Cold air vs warm air

same air / fuel ratio, therefore more air = more gas
Old Jul 27, 2005 | 03:21 PM
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Default RE: Cold air vs warm air

How are cars getting more air in summer?
Old Jul 27, 2005 | 03:48 PM
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Default RE: Cold air vs warm air

they get less air in summer, burning less fuel, therefore better economy.
in winter, they get more air, more fuel, less economy.
Old Jul 27, 2005 | 04:06 PM
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Default RE: Cold air vs warm air

also in the winter one tends to run their heat, and that runs the alternater, wich in turn, WASTES GAS

Old Jul 27, 2005 | 04:22 PM
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Default RE: Cold air vs warm air

ORIGINAL: sandcracker21

also in the winter one tends to run their heat, and that runs the alternater, wich in turn, WASTES GAS


Huh.......The alternater runs no matter what.If anything the AC would burn more gas when its running
Old Jul 27, 2005 | 04:30 PM
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Default RE: Cold air vs warm air

An engine will be more efficient at a higher temperature up to the point of boiling the coolant. That or people don't add air to their tires as it gets colder.
Old Jul 27, 2005 | 04:35 PM
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Default RE: Cold air vs warm air

ORIGINAL: LightSmith

An engine will be more efficient at a higher temperature up to the point of boiling the coolant. That or people don't add air to their tires as it gets colder.
Say what????????I might have to have my dog translate that for me
Old Jul 27, 2005 | 04:42 PM
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Default RE: Cold air vs warm air

BA-WHOOF!! Whoof!

Uh, wait a minute. A hotter combustion chamber will burn the mixture more efficiently, a more complete burn. This is only true until coolant starts to boil, usually around the exhaust valve area first. Once detonation starts, your efficiency is gone.

You've gotten the tire part where the tire pressure drops as the temperature goes down, right?
Old Jul 27, 2005 | 04:59 PM
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Default RE: Cold air vs warm air

I still don't get how an engine is getting less air in summer, and more in winter. How is that?

The heater thing is irrelevant, as stated above, alt runs all the time.

The hotter combustion chamber seems feasible, can anyone confirm that? Don't all engines get up to a hot temperature eventually, though, regardless of outside temp?



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