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Old 09-02-2009, 02:14 AM   #1
Sports Wagon
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OMGHi2U Altitude and Temperature

Since moving to Utah I've always wondered what affect altitude had on an engine power wise.

I read there is a loss of 3 to 4 percent of power per 1,000 foot gain in altitude seems to be the rule on a naturally aspirated engine.

When it comes to temperature generally, there is a loss of one percent of
horsepower for every 6 to 10 degrees increase in induction air temperature.
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Old 09-02-2009, 04:59 PM   #2
justincredible
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Quote:
Originally Posted by Sports Wagon View Post
Since moving to Utah I've always wondered what affect altitude had on an engine power wise.

I read there is a loss of 3 to 4 percent of power per 1,000 foot gain in altitude seems to be the rule on a naturally aspirated engine.

When it comes to temperature generally, there is a loss of one percent of
horsepower for every 6 to 10 degrees increase in induction air temperature.
On a FI vehicle it's not much.
On an NA you can feel the loss.
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Old 09-02-2009, 06:21 PM   #3
Murphdog
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From everything I've read 3% is about right. Non NA cars arent as much but should be pretty close to that same figure. To compensate we turn up boost but that will heat the air more and become less efficient. And to help us out even more we get the amazing 91 octane fuel. About temp I'm not sure what the increase/decrease is with it.
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Old 09-02-2009, 07:26 PM   #4
Sports Wagon
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I wonder what the difference of HP loss is as a result of air density vs. atmosphere pressure at altitude.
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