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How does ethanol cool intake air ?

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#1
So i have been doing a lot of research on fuel and i found something that relates to a similar conversation here recently. So several articles online i found state that ethanol (and methanol), since they are alcohols, will vaporize when injected and end up cooling intake temps. I have heard people here i think discuss it helps cool the cylinder temps and that makes sense as it's injected there and turns to vapor. But how does what goes on in the engine block affect my air intake, which ultimately makes its way to the turbo?

Two separate articles mention not even needing an IC due to the cooling effect of ethanol. Now they may be talking about full on e85 but the question is still the same. Is it a matter of a cooler engine bay means there's less heat to affect the intake pipeline? If you want to read a couple of the articles they are HERE and HERE. Im not really questioning things one way or another, im just curious if it's true, how it works.

For reference, the first link i posted says the following about inlet temps and ethanol/methanol causing cooling.

"Evaporative Cooling: Gasoline atomizes when sprayed into an engine while ethanol vaporizes. Liquids absorb tremendous amount of heat when they vaporize. For ethanol, it’s 387 BTU/lb. This latent heat of vaporization from one pound of ethanol is therefore equal to the energy required to cool a gallon of water by 46.4 degrees Fahrenheit. Brrr!

Because gasoline does not vaporize, intercoolers are used in most boosted applications as a means of reducing air inlet temperature following its compression. These intercoolers can be air to air, or liquid to air. In either case, they take up space, add weight, complexity and cost while typically reducing the effectiveness of the engine cooling system. E85 does such a good job knocking down inlet air temps that no intercooler is needed."

So again, how does the cooling effect within the cylinders affect the intake of a car when they are not directly connected?
 


Clint Beastwood

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#2
So i have been doing a lot of research on fuel and i found something that relates to a similar conversation here recently. So several articles online i found state that ethanol (and methanol), since they are alcohols, will vaporize when injected and end up cooling intake temps. I have heard people here i think discuss it helps cool the cylinder temps and that makes sense as it's injected there and turns to vapor. But how does what goes on in the engine block affect my air intake, which ultimately makes its way to the turbo?

Two separate articles mention not even needing an IC due to the cooling effect of ethanol. Now they may be talking about full on e85 but the question is still the same. Is it a matter of a cooler engine bay means there's less heat to affect the intake pipeline? If you want to read a couple of the articles they are HERE and HERE. Im not really questioning things one way or another, im just curious if it's true, how it works.

For reference, the first link i posted says the following about inlet temps and ethanol/methanol causing cooling.

"Evaporative Cooling: Gasoline atomizes when sprayed into an engine while ethanol vaporizes. Liquids absorb tremendous amount of heat when they vaporize. For ethanol, it’s 387 BTU/lb. This latent heat of vaporization from one pound of ethanol is therefore equal to the energy required to cool a gallon of water by 46.4 degrees Fahrenheit. Brrr!

Because gasoline does not vaporize, intercoolers are used in most boosted applications as a means of reducing air inlet temperature following its compression. These intercoolers can be air to air, or liquid to air. In either case, they take up space, add weight, complexity and cost while typically reducing the effectiveness of the engine cooling system. E85 does such a good job knocking down inlet air temps that no intercooler is needed."

So again, how does the cooling effect within the cylinders affect the intake of a car when they are not directly connected?
It slows the cycle of heat generation and retention. Less cylinder heat radiates less engine bay heat which becomes less heat soak which means less intake charge heat which means less cylinder heat etc.
 


TyphoonFiST

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#3
Or you could be like Mopar and use the A/c Freon to cool the in coming charge in the supercharger.

Sent from my SM-N950U1 using Tapatalk
 


OP
TalkToTheFiST
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Thread Starter #5
It slows the cycle of heat generation and retention. Less cylinder heat radiates less engine bay heat which becomes less heat soak which means less intake charge heat which means less cylinder heat etc.
Ok ty for the info, then it is as simple as the entire engine bay heats up and everything is affected.
 


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#6
The goal of atomizing gasoline is for it to vaporize before combustion. There are events that can cause less than full vaporization and engines and your wallet don’t enjoy that
 


HBEcoBeaST

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#7
Intake temperature and cylinder temperature are two different things. Your intake is BEFORE the combustion chamber so intake temperatures affect temperature inside the cylinder, but not vice versa [unless the engine is physically heating the intake air (i.e. open air intake)].

intercoolers are far simpler and more reliable than relying on seperate meth or h20 injection. Just like nitrous, methanol/water systems need constant filling and when you run out of juice, you can ruin your motor. Lots of $$$ for a safe set up when an upgraded intercooler is more reliable and cheaper. There's a reason most of us don't run methanol kits, sure we'd love the power, but it's a hassle, and to really get the most of it, you'll need a standalone failsafe like Stratified's Guardian Angel ($$$$).

Our tiny intercoolers don't weigh very much and don't block air to the radiator. If intake tubing adds 'complexity' I don't know what running seperate injectors, tank, fuel lines, standalone fuel safety module and having to fill up with methanol on a constant basis qualifies as:unsure:
 


OP
TalkToTheFiST
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Thread Starter #11
The goal of atomizing gasoline is for it to vaporize before combustion. There are events that can cause less than full vaporization and engines and your wallet don’t enjoy that
So that sounds like an advantage for ethanol, that it doesn't have to be atomized no? Also another thing i may as well point out i thought was interesting, was they talked about the extra oxygen making up 30% of the ethanol molecule. In the first link they mention that means an ethanol fuel doesn't need as much oxygen to combust, reducing the demands on the intake volume. Has anybody discussed this here, is it true?

"Highly Oxygenated: Being 85% ethanol means that E85 is carrying along about 30% oxygen in liquid form. The remaining 70% is carbon and hydrogen which are the fuel burned (oxidized) by the oxygen during combustion. You get to spray this liquid oxygen through your carb or injectors thereby reducing the demand for oxygen from the air inlet stream. If you fuel system is adequately sized, you need less boost to stuff the cylinders with the same amount of oxygen, carbon and hydrogen. "
 


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#12
Fuel needs to reach a state of vaporization for optimal performance no matter its makeup
 


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#13
DI engines have the injectors in the combustion chamber and there is less time for vaporization. This brings in the importance of fuel and tuning into making safe power.
Being power hungry is fine but overlooking the finer aspects can blow your shit up. Not all tuners are made equal.
Stock tuning I’d go with Randy or Stratified. They are beyond qualified to make critical decisions.
Big turbo I recommend Mitch at CPE because of my own results. 🇺🇸
Edit: I am in no way implying Randy or Stratified aren’t qualified to tune big turbos. I am only relaying my experience with them on the stock hair dryer
 


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