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Have you noticed that your Challenger has more power when the air is cold and dense in the winter?

It's well documented that for every 10 degree temperature change the power can drop or rise ~5-7whp.

With the temperature in the 30s, I can really feel the extra power in my 2009 SRT 6.1. Have you guys also noticed this with your Challengers?
 

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Have you noticed that your Challenger has more power when the air is cold and dense in the winter?

It's well documented that for every 10 degree temperature change the power can drop or rise ~5-7whp.

With the temperature in the 30s, I can really feel the extra power in my 2009 SRT 6.1. Have you guys also noticed this with your Challengers?
Yes, the engine sounds and feels more snappy. However at -41 like it was the other morning, and horsepower gain is more than negated by the fact that the trans fluid and gear oil are thick as molasses. My car won't even roll down the driveway slope in neutral.
 

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Discussion Starter · #3 ·
Yes, the engine sounds and feels more snappy. However at -41 like it was the other morning, and horsepower gain is more than negated by the fact that the trans fluid and gear oil are thick as molasses. My car won't even roll down the driveway slope in neutral.
Yes, but how about after you have driven your car for 30 minutes and everything is warmed up?
 

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Density Air calcs. Mandatory for pilots, near mandatory for drag racing etc.

Consider a day at 1000’ elevation and it is a warm day. 85 degrees, 67 degree dew point. That car is developing 95.3% of its available theoretical power.

Now like today here in MN. 1000’ again, it is 15 degrees, DP is 1.
Same car. Developing 106% power today! If I drove my Redeye in the winter, theoretically today it would run like a Demon with a crate PCM at 844 hp!

You sure can feel that near 10% difference in any car!
 

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Thanks Cuda for the 10° information. I didn't know that. (y)

Colder, denser air has more oxygen molecules in it. Engines like cold, dense oxygenated air. The down side is that with that cold, dense, horsepower making air comes cold roads which aren't particularly good for traction.
 

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2016 Challenger R/T Plus Shaker
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This is why Dodge and Plymouth had functional cold air systems from '69-'72. The Ramcharger for Dodge and the Air Grabber for Plymouth. Both shared the coolest system, the Shaker, although Plymouth called it the "Quivering Exposed Cold Air Grabber" in one ad that I remember. Thanks for the hard numbers, Cuda 340. I do notice the performance difference in different temperatures.
 

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2020 Dodge Challenger Hellraisin Scat Pack
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Thanks Cuda for the 10° information. I didn't know that. (y)

Colder, denser air has more oxygen molecules in it. Engines like cold, dense oxygenated air. The down side is that with that cold, dense, horsepower making air comes cold roads which aren't particularly good for traction.
And less moisture.

Have you noticed that your Challenger has more power when the air is cold and dense in the winter?

It's well documented that for every 10 degree temperature change the power can drop or rise ~5-7whp.

With the temperature in the 30s, I can really feel the extra power in my 2009 SRT 6.1. Have you guys also noticed this with your Challengers?
Have noticed what felt like a bit peppier performance on a cooler day. Just today with the air temperature at 30F my M-B cargo van engine felt just bit more responsive to the throttle.

However, I have to admit I have been "hitting" the freeway with the van recently driving nearly 18 miles on the freeway to and back -- at 70mph -- from the place my Scat Pack is being repaired. I know from experience engines perk up some after some freeway miles. 18 is fewer miles than what I have found at least with other engines makes a difference. Around 40 miles is what I found some other engines liked.

So I'm not sure the cooler temperature or the freeway miles accounts for the slight but noticeable improvement in how the engine feels.
 

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Discussion Starter · #11 ·
This is why Dodge and Plymouth had functional cold air systems from '69-'72. The Ramcharger for Dodge and the Air Grabber for Plymouth. Both shared the coolest system, the Shaker, although Plymouth called it the "Quivering Exposed Cold Air Grabber" in one ad that I remember. Thanks for the hard numbers, Cuda 340. I do notice the performance difference in different temperatures.
You almost got it right. I had a 1971 'Cuda with a shaker hood. It was called the "I.E.Q.C.A.G." The Incredible Exposed Quivering Cold Air Grabber.
 

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I thought the word "Incredible" might have been part of it, but I couldn't remember the exact order of the words either. But remember, I am working from a somewhat compromised memory on most things that I post. Too many things to remember, and my brain reached the full mark a long time ago and so I forget things to make room for other things. I will try to do better. Thanks.
 

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Density Air calcs. Mandatory for pilots, near mandatory for drag racing etc.

Consider a day at 1000’ elevation and it is a warm day. 85 degrees, 67 degree dew point. That car is developing 95.3% of its available theoretical power.

Now like today here in MN. 1000’ again, it is 15 degrees, DP is 1.
Same car. Developing 106% power today! If I drove my Redeye in the winter, theoretically today it would run like a Demon with a crate PCM at 844 hp!

You sure can feel that near 10% difference in any car!
A point of clarification for those of us that are "Dew Point" challenged. These 2 examples are using 55% humidity.
 

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The opposite is also true, many complain their Hemis are down on power when the weather is hot. This was about the Hellcat


It's not unique to the Hemi of course, and it's well known what a difference temperature can make. How many fans on the engine during a dyno run?


A Guy
 
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A point of clarification for those of us that are "Dew Point" challenged. These 2 examples are using 55% humidity.
Pure coincidence not intended. RH is not used in DA calcs. I hate relative humidity readings. Since it deviates relative to the temperature it should be “relatively” worthless to most people.

When it is 100 degrees and the DP is 75 degrees, it is horrible outside. 45% relative humidity don’t sound bad right? Do folks understand at that clearly? It can be rough.

Evening time, same place. 80, and 75 degree DP remains in this horrible location. 84 % relative humidity. Now that gives an impression it is “humid”.

I have listened to people and they don’t have a clue, that simply the dew point IS the measurement and reading for the moisture in the air. Relative humidity is only the expression of how near the dew point or like yesterday in MN the frost point is relative to the current air temp.
 

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The first cold start of the day does sound better in cold weather. Has more of an initial "crack" to it.
That's just the fact the weather is colder and in cold weather noise is transmitted better from among other things the rubber/plastic bushings/seals and such are firmer.

Encountered this "often" in CA. Would get in a cold car in the AM and start the engine. Noisy. Get into the same car (at the office) after being parked out in the sun all day and the car thoroughly warmed up and it was pretty quiet upon engine start -- it had been 8+ hours since the engine was last run so it was not hot from being recently run -- and the car just didn't make as much noise when underway.
 

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Pure coincidence not intended. RH is not used in DA calcs. I hate relative humidity readings. Since it deviates relative to the temperature it should be “relatively” worthless to most people.

When it is 100 degrees and the DP is 75 degrees, it is horrible outside. 45% relative humidity don’t sound bad right? Do folks understand at that clearly? It can be rough.

Evening time, same place. 80, and 75 degree DP remains in this horrible location. 84 % relative humidity. Now that gives an impression it is “humid”.

I have listened to people and they don’t have a clue, that simply the dew point IS the measurement and reading for the moisture in the air. Relative humidity is only the expression of how near the dew point or like yesterday in MN the frost point is relative to the current air temp.
I read up on relative humidity & dew point long time ago & forgot whatever I learned.

If I want to fill my tires with as dry air as possible, do I bring my portable air compressor inside & fill it up where the air is 72°F and 30%RH, or fill it up outside where it's 23°F and 57% RH?
 

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I read up on relative humidity & dew point long time ago & forgot whatever I learned.

If I want to fill my tires with as dry air as possible, do I bring my portable air compressor inside & fill it up where the air is 72°F and 30%RH, or fill it up outside where it's 23°F and 57% RH?
Who cares it is not relevant. Get over it, dew point is simple and not calculated on another variable.
 
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