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Discussion Starter · #1 ·
Ok, So I have a math question. If ANYBODY can help please do. I'm trying to find out if there is any formula's for determining how many CFM's of air are needed to burn a certain amount of fuel. If anybody knows of anything please feel free to PM me or reply to this. I'm just trying to make my truck as fuel efficient as possible with the prices of that liquid gold sky rocketing. Thanks everyone.
 

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Don't even worry with cfm a good intake and exhaust with a tuner that adds more timing and fuel pressure to atomize the fuel going into the the engine will get you great mileage.
 

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Discussion Starter · #3 ·
I think you totally missed what I was asking. I'm not looking for info on a CFM intake. I need to do some math and figure out how much air it takes to burn "X" amount of fuel that my injectors will be putting in my cylinders. I'm trying to get the air/fuel ratio as close to 1:1 as humanly possible. Tuners are useless to me anyway, I'm only rollin' 12 valves deep, all mechanical. Anywho, not trying to be mean, just clarifying what I'm looking for, mathematical stuff.
 

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I DONT BELIEVE IT!
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here's good math
 

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Too many variables, block temp, altitude, humidity, etc to get any kind of practical data. Fuel efficiency starts by having a surplus of o2 to ensure all the fuel burns, not an exact amount of o2. That would be counterproductive.
 

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Discussion Starter · #7 ·
Yeah I see your point, I guess I just need to try and approximate. Probably just gonna be alot of trial and error tuning I guess. If there is anything useful though, keep posting guys.
 

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It's really a chemisty question.

Find the balanced chemical equation for the combustion of cetane (cetane's close enough?).

Find the molar volume of liquid cetane.

Find out how many mols of oxygen are in a mol of air.

Use the combined ideal gas law to calculate the volume of air that contains the number of mols your looking for, at your boost pressure and intake temperature.

After you do that, tell me how to determine the pressure and temperature of the combustion-chamber gases at any given crankshaft position. I need to program that forumula into LabView to keep my fumigated methanol from detonating.
 

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Mopar1973Man.Com
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Well its a chemistry problem and computer problem too...

Like Dodge Cummins software tend to increase fuel flows in colder air (IAT Sensor < 100*F) and reduced fuel flow in warmer air (IAT sensor > 100*F)

Colder engine coolant tends to do the same too. Anything under 190*F tend to increase fuel flow.

More boost pressure tend to lower Auto-ignition temps.

Highier cetane fuel tend to be lower in BTU content. But ignite easier for colder weather. But low cetane fuel tends to be high in BTU content but burns slowly.

And much more factors...:w:
 

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Discussion Starter · #10 ·
Welp, guess this might be a little bit more complicated than I originally thought, oh well. I'll keep researching, but thanks for all the replys everyone.
 

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Welp, guess this might be a little bit more complicated than I originally thought, oh well. I'll keep researching, but thanks for all the replys everyone.

Alright you two einsteins, If you have that much time on your hands to be worrying bour air/fuel mixture and combustion rates of such,,,
My best advice would be, go find a girlfriend to pre-occupie you thoughts.

jk of course, but you are killin me. filler up and hammer it. lol
 
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