superheated fuel

If fuel thermally expands, then there will be less fuel in a given volume of fuel, so you will loose power. The fuel also is relied on to cool the injectors, and I'd think that the P-pump is at least somewhat cooled by the fuel on top of the oil.

Fuel temperature is monitored on many, if not all, modern OTR engines, and they all run a fuel cooler as well. The cooler the fuel the better, especially when that fuel is an injection pump's only source of cooling.
 
Begle1 said:
If fuel thermally expands, then there will be less fuel in a given volume of fuel, so you will loose power.
Click to expand...

are you sure about that?

not the less molecules per sq inch part...the less power part

who is to say that 140° fuel doesnt burn cleaner (read more effecient) than 80° fuel?

not saying that it does...cuz i dont know

but all the cummins i have seen have a fuel heater on them...and the heater runs when ever the engine is running - regardless of temp

who knows?

we need more internet engineers on here

yea, thats what we need...
 
I have read in OEM literature that hot fuel takes power. Or maybe that was crappy tech school literature that has no real credibility at all... For the sake of my own Internet cred, I'll say that it was OEM literature.

Really cool fuel won't flow or atomize very well and has it's own issues there, but I think they stop heating up fuel once it gets to around 60-70 degrees. It's definitely not there with the intention to get it as hot as possible.

I think that hot fuel would atomize better than cool fuel, so if you compensate for the lack of density by spraying more fuel, you could burn more fuel and get more power... But I don't think anything really compensates for fuel temp, and last time I mentioned that on here all the other Internet engineers laughed at me...

Do fuel maps on OTR engines take fuel temperature into account? And increase fuel delivery with hotter fuel? I wouldn't be surprised if they did.
 
I know my truck lopes once the fuel and engine get to operating temperature but when everything is cold it's smooth as silk.
 
thats interesting - wonder why?

just started mine for the first time since installing all this stuff - had to turn the idle up a bunch but it is as smooth as silk - have not got it to operating temp or driven it yet

ddp 4's @ 20.5°

4k gsk

stupid fuel system set at 1 psi fuel pressure

don

oh - and i shot a vid of the fuel volume - its pretty crazy...will fill a 5 gal can in less than 2 minutes (and there is only 10 gals in the tank!) (the closer to full it is the higher the volume should be) can still hear the fuel pump tho - with the engine off
 
Begle1 said:
Do fuel maps on OTR engines take fuel temperature into account? And increase fuel delivery with hotter fuel? I wouldn't be surprised if they did.
Click to expand...

i dont know what a otr is but pro stock harleys do. the motec compensates for fuel temp and fuel pressure too (but thats efi - totally different deal)
 
DTanklage said:
i dont know what a otr is but pro stock harleys do. the motec compensates for fuel temp and fuel pressure too (but thats efi - totally different deal)
Click to expand...

"Over the road"'; ISX's, N14's, 60 Series, 3406's, et cetera.


I would think that the same theory would apply to EFI; I imagine that they inject more fuel at a higher fuel temperature than a at a lower fuel temperature?
 
DTanklage said:
how you gonna do that?

they (pressure and volume) are inversly related

increase in pressure creates a decrease in volume
Click to expand...


Are you saying there is no way possible to raise the pressure without losing volume?

Stand in front of an open fire hydrant. There is pressure and volume for you.
 
Cummins Driver said:
Are you saying there is no way possible to raise the pressure without losing volume?
Click to expand...

not the way my system is plumbed, no

these are simple known laws

i didnt make em up - they are not my laws

why dont you read about them instead of trying to knock me over with a fire hydrant?

lol

you might wanna be careful what you say on here too...i was kiddin around about some soot on a guys engine compartment and almost got banned

i laughed at it your hydrant - cuz thats how i am - something tells me the mods dont have much of a sense of humor

don
 
Begle1 said:
If fuel thermally expands, then there will be less fuel in a given volume of fuel, so you will loose power. The fuel also is relied on to cool the injectors, and I'd think that the P-pump is at least somewhat cooled by the fuel on top of the oil.

Fuel temperature is monitored on many, if not all, modern OTR engines, and they all run a fuel cooler as well. The cooler the fuel the better, especially when that fuel is an injection pump's only source of cooling.
Click to expand...

I totally agree...take a 3406E/C15 cat for example and make it "think" it's getting hot fuel when it's not. There is a reason for fuel coolers and fuel temp sensors. From the performance standpoint I would install a fuel cooler on a truck before I would lower the regulated fuel pressure.

Cummins Driver said:
Are you saying there is no way possible to raise the pressure without losing volume?

Stand in front of an open fire hydrant. There is pressure and volume for you.
Click to expand...

It's simple...a bigger or higher volume supply pump!
 
the fuel is going thru my pump so fast it is crazy

i dont know that it would have much time to disapate heat if i ran it thru a cooler

good thing i didnt plumb in a second feed (front plug)

think if you do that once the pump is full the fuel will take the path of least resistance and go in the front and out the return like pronto

this pump is gonna really run cool

until the fuel gets hot!
 
DTanklage said:
not the way my system is plumbed, no

these are simple known laws

i didnt make em up - they are not my laws

why dont you read about them instead of trying to knock me over with a fire hydrant?

lol

you might wanna be careful what you say on here too...i was kiddin around about some soot on a guys engine compartment and almost got banned

i laughed at it your hydrant - cuz thats how i am - something tells me the mods dont have much of a sense of humor

don
Click to expand...

You can raise the pressure and keep your volume, but of course you are going to have to modify things. I know how pressure and volume relates. Its pretty simple, but you said there was no way to raise the pressure and keep the volume. There is, you just would have to change some things. :Cheer:

As for the mods. If i get banned for talking about pressure and volume out of a fire hydrant, then so be it:hehe:

Eric
 
Cummins Driver said:
You can raise the pressure and keep your volume, but of course you are going to have to modify things.

I know how pressure and volume relates.

Its pretty simple, but you said there was no way to raise the pressure and keep the volume.

There is, you just would have to change some things.

Eric
Click to expand...

go on...

would love to here erics laws

lol
 
DTanklage said:
you might wanna be careful what you say on here too...i was kiddin around about some soot on a guys engine compartment and almost got banned

i laughed at it your hydrant - cuz thats how i am - something tells me the mods dont have much of a sense of humor

don
Click to expand...
Are you kidding?

Are you familiar with the mods on here?

If anything most of our mods have over developed senses of humor:hehe:
 
DTanklage said:
go on...

would love to here erics laws

lol
Click to expand...

My laws? They arent my laws. You already know how it works, or at least you said you did. :bang

You said as pressure goes up, volume decreases, right?

So as you keep 5psi over your boost pressure, you will have a lot of volume and not much pressure at idle, right? Then when you are making 40psi boost, you will have 45psi fuel pressure, and volume will go down, right?

You dont need much volume at idle, you need the volume and pressure when you are burning the fuel(high boost), so why not run a regular pump/regulator setup? It would seem to me your setup would have no benefit over a fixed PSI setup under boost, when you really need the volume and pressure.
 
look, the volume of supply is fixed

i can not change that

have added a sump, radiused and polished all the orfices inside my pump, even radiused the fittings that didnt come that way

the system will move close to 200 gals per hour

what i can vary however, is the amount of that volume that is returned to the tank

the higher the pressure - the less volume is returned to the tank

(the more that it 'held' in the pump)

if you read the first post it says that the regulator is after the injection pump and that everything my lift pump can produce is flowing thru the injection pump

how quickly is it flowing thru there?

that is determined by the pressure (or restriction if you rather)
 
Cummins Driver said:
....when you are making 40psi boost, you will have 45psi fuel pressure, and volume will go down, right?
Click to expand...

the volume that is returning to the supply tank will decrease

yes

i am not certain that you understand how my system is set up

anyways, it works GREAT

hope your system works just as good

make it a great day
 
Cummins Driver said:
....you need the volume and pressure when you are burning the fuel(high boost), so why not run a regular pump/regulator setup?

It would seem to me...
Click to expand...

because i already had most of this stuff layin around

and mesa hose sponsors me so brooks gave me the hose and any hose ends i was short (which ended up being quite a few)

thanks mesa hose

and it has high pressure and plenty of volume under boost. why? because in that state the return volume is decreased. afterwards, when i lift, return volume increases (hopefully cooling the pump)
 
guessin at zero

and dont think it will move that if it aint sumped

180 gph is a lot of fuel

100m prefilter a 2m post megafilter with 6 feet of -6 hose on the back side of it and it will shoot fuel almost all the way across the street
 
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