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Considering the extreme temps of the compressed air leaving the turbo under high boost, does it really make any difference what the temp of the air is entering the turbo? Specifically, will it make any difference if the air filter is isolated from the engine compartment and ingesting air at ambient, say 85*F, versus being under the hood with air temps of say 150*?
 

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aka: mOtOrHeAd MiKe
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Some would argue, no, based on the fact that any matter can only hold so much heat, and only so much heat can be transfered into the air from the "compressing machine".

However, it is safer to assume that a higher air density charge flowing into said "compressing machine" will not pick up as much temperature change by the time it reaches the discharge point.

I suppose every little bit helps. The best way to tell is using thermocouples/MATs to determine the temperature difference in cold air vs. underhood validity.

I ate my "Sound Smart Weaties" this morning. :D
 

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Yup,it works.
Change your your temps to SI units and run your PV/T formula.
Assume 200 F for an underhood K&N and 85 or so for a cold air inlet.
Remember that any temp drop to the inlet of the turbo let's the turbo think it's bigger and hence will work more efficiently.
I found I had to up my base fuel about 8 psi to get it to work when I first installed it.
You could also assume about 2% inlet efficiency losses due to the longer inlet length,however that gets way more than offset by the density increase[I think you'll find around 10%]
 

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yea, sounds good to me. c'mon Mike, tell the truth, u took a fluid dynamics class in addition to interior architecture...didn't u? heh heh, hey i admire your skills, think you can draw me up something for my lame-azz boring house? headbang

honestly, the way i think about and could possibly prove it in simple terms is: drinking a soda...u take an ice cold soda at say 60 degrees and ingest it into your body with a constant temp of 98.6 degrees ...it still take a few minutes for that liquid to reach the temp of your body. if i'm correct though, depending on the gas, it can change temp faster than liquid though...anyone, anyone....bueller, steve beuller ? ? ? :confused:
 

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aka: mOtOrHeAd MiKe
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NOSjohnWE4:
yea, sounds good to me. c'mon Mike, tell the truth, u took a fluid dynamics class in addition to interior architecture...didn't u? heh heh, hey i admire your skills, think you can draw me up something for my lame-azz boring house? headbang
Sure, my consultation fee is $75/hour. :D
(To bad that isn't how much I make. :()
 

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It makes a noticible difference as RK points out.

The turbo operates in a more efficient range even tho the differential temperature is the same. The compressed charge being cooler when it enters the combustion chamber is also less likely to suffer detonation.

Delivering a denser charge requires more fuel as RK also pointed out. This is very obvious if you live in an area where the summer winter temperature swings are high. Tune for summer, detonate due to leaness all winter. :) :)
 
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