Hot fuel vs. Cool fuel

Duramax2006

Duramax2006

GM TECH @ FENDER GMC
Joined
Mar 28, 2008
Messages
184
Okay I've heard all kinds of opinions on this one does a Diesel run more efficient on warm fuel or cool fuel please help me out on this cause if it like cool fuel i'm going to mount a SPAL cooling fan on the fuel cooler of my 2006 Duramax
 
Seems to be a lot of conjecture on this one.

What I can't understand about the cold fuel thing, is that the fuel spends significant time in hot things after you cool it. Like hot CP3s and hot rails and hot injectors in hot heads. I have a hard time believing that cooling it better in the cooler actually affects the injected fuel temp (which is this only thing that would really matter IMHO)

It might help your CP3 last longer because there's a good bit of bypass there and maybe it stays a bit cooler, dunno. The right lubricity additive is probably a far better tactic there anyway.

I would just bet a lot that no matter what you do with the tank temp, the injected fuel temp is gonna be 190+/- degrees F. I have yet to see good data that demonstrates cold fuel does anything at all.

Now if someone shows up with a good set of data, I'd certainly pay attention to it, but lacking that, I'm skeptical.

If you came up with a method to keep everything cold all the way to the nozzle, you might have something.
 
What Matt said

I would have to agree with Matt (did I just say that lol) on this one. It would be hard to keep it cool long enough. Jeff
 
We are going to play with a cryogenic cooler that cools fuel before it cools the air. time will tell
 
We had a cooler on a truck and at idle, you could see the EGT's drop around 50 degrees while idling.
 
zstroken said:
We had a cooler on a truck and at idle, you could see the EGT's drop around 50 degrees while idling.
Click to expand...

How much of a cooler, and where was it?

Could you toggle it on and off several times to prove it wasn't just the thermocouple playing games with you?
 
When sitting in line you could turn it on and see it. It was a coil out of a geothermal unit.
 
i would think you would want the fuel to run on the warm side in order to inhance the combustion because compression burns the fuel and the better the fuel burns the more efficient use of the fuel is derive if you put off heating up the fuel to combustion in a short you are delaying the process GM placed a fuel heater to make sure the fuel was at its optimun befor it reached the combustion chamber now how much heat is to much i dont know but to cold is not good now a gasser motor cold fuel works well but we are running diesels diesel fuel needs a good additive that has all the good stuff that our oil companys have refiened out for emissions well back to making subs this $5 sub deal is killer:hehe::hehe:$.02$.02$.02
 
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Some thoughts - most big rigs have, from my understanding, big fuel coolers.

I am told that Cold fuel is dense fuel becuase there is less entrained air, like cold air is denser - whcih definitely makes more power.

There is no question that coler fuel will help your ip live longer if it helps remove heat

Empirical evidence? - no - but my truck has a fan cooled fuel cooler on it and the truck seems to run better.
 
Hotter fuel will get better atomization when it is injected. Better atomization results in better/ more complete combustion.

Cooler fuel is to cool off the injection pump.

Thicker, cooler fuel might get better atomization on a low 7-10K psi p pump because it may develop better injection pressure when it is cool. I said may, I'm not an injection expert, just very familiar with atomization and combustion quality.
 
flash point for diesel ~140-150* presure increase flash piont vaccum decreases it.

colder= denser= more fuel in the shot
hot= thinner= less and possible better atomiztion

the dmax will limp if hte fuel temp goes above a set temp im sure the CR dodges are the same way.

drag races for years have always used a cool can to cool the fuel/gas and have pick up qunatifiabnle results that way.

im sure there is power to be had but there is still a happy medium that needs to be kept..
 
in michigan we are forced to run winter diesel because of the low temps at low temps diesel will jell unless there is an additive if one could control the temp of the fuel to the injectors on a motor that is on a dyno it would be interesting so see where how when how much power changes from fuel temp alone also note that what works on a gasser motors doesnt mean it will work on diesel motors the one thing that does work on both is cooler air and over years of racing very very cold air isnt always the ticket crap more people wanting subs will this sub deal ever end got to go:bang
 
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