Technical How can a valve cover heat up fuel lines?

Torgus

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Fun math:

Given Horsepower x .70 lb fuel/hp = lbs of fuel for given horsepower
600 x .70 = 420
420 / 6.25 lbs/gal = 67.2 gph
67.2 / 60 = 1.12 gpm
1.12 / 2 = .56 gallons every 30 seconds.

While at WOT you will use half a gallon in 30 seconds if you make 600whp. That is too much fuel to be warmed up by 2 inches of fuel line. It's moving too fast to pick up any meaning latent heat in the fuel line. A fuel line that is not being warmed up by the valve cover mind you.

This much fuel:
15977501_main.jpg


In 30 seconds


Edit: What is the volume of a fuel line?
 
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fmorelli

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I love the math, but there are some assumptions here. For starters hardest load on an engine is during transition. So that's going to max WHP, not at full humping steady bigly whp.

That said, in the summer time my fuel is cooking up pretty good under the car - I know this because of the Fuel-It ECA giving me actual fuel temp readings. I'm curious what the actual fuel temp is at the injector. That is, what the rise might be. I wouldn't mind getting my fuel temps down before it ever got to the HPFP.

And what is the rise in fuel temp after the fuel is compressed by the HPFP? (Someone can do the math on that I suspect). All that said, I'd just like to get heat out of my engine compartment and feed the correct amount of fresh air INTO my air tract - two areas I feel would increase reliability (and maybe HP). This seems to have been a community where platform priority is, 1) WHP, 2) WHP, .... N - 1) WHP, N) reliability, N+1) suspension to manage WHP (see 1 to N), N+2) handling.

But all that said, I'm feeling a real need for a cold cup of creamy milk. Not sure why that is ... đź‘€

Filippo
 
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Torgus

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That said, in the summer time my fuel is cooking up pretty good under the car - I know this because of the Fuel-It ECA giving me actual fuel temp readings. I'm curious what the actual fuel temp is at the injector. That is, what the rise might be. I wouldn't mind getting my fuel temps down before it ever got to the HPFP.


While I think it would be very interesting to see the fuel temp rise after each set of pumps. I don't think the data will be very helpful. What I mean is I doubt it will be practical to install a fuel cooler because of cost and complexity and small to no gains. Especially as you would ideally want the cooler after all the pumps, before injectors. That means a high pressure environment. Also in a return system this means you are trying to cool all of the fuel constantly. Assuming you are using the AC to cool the fuel you would gain more HP deleting the compressor than by cooling the fuel with it.

How much does one Walbro 525 heat up the fuel?
How much does two Walbro 525s heat up the fuel?
How much does two HPFPs, one sped 30% over, heat up the fuel?
How much does converting to a return from a dead head(stock) fuel system heat up the fuel?
How much does adding in a surge tank and a lift pump heat up the fuel?

They make fuel coolers. They also make Co2 intercooler sprayers. I don't think either is really practical in our application. Marty may disagree.

I still want to hear about his magical octane booster that 250MLs(0.066043 of a gallon) makes 16 gallons of 93 e00 have an AKI like e20.
 

The Convert

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While I think it would be very interesting to see the fuel temp rise after each set of pumps. I don't think the data will be very helpful. What I mean is I doubt it will be practical to install a fuel cooler because of cost and complexity and small to no gains. Especially as you would ideally want the cooler after all the pumps, before injectors. That means a high pressure environment. Also in a return system this means you are trying to cool all of the fuel constantly. Assuming you are using the AC to cool the fuel you would gain more HP deleting the compressor than by cooling the fuel with it.

How much does one Walbro 525 heat up the fuel?
How much does two Walbro 525s heat up the fuel?
How much does two HPFPs, one sped 30% over, heat up the fuel?
How much does converting to a return from a dead head(stock) fuel system heat up the fuel?
How much does adding in a surge tank and a lift pump heat up the fuel?

They make fuel coolers. They also make Co2 intercooler sprayers. I don't think either is really practical in our application. Marty may disagree.

I still want to hear about his magical octane booster that 250MLs(0.066043 of a gallon) makes 16 gallons of 93 e00 have an AKI like e20.
I have to disagree with some of the assertions here. The cooler the fuel going into each pump, the cooler it will be coming out of each pump, and the cooler the fuel, the higher the volume. Same concept as providing cold air to a turbo versus hot air. Sure both will be hotter after compressed, but the cooler the air that goes in, the cooler the air that comes out.

I totally agree that the M18 VC is not adding heat to the fuel though.
 

rev210

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To be fair does fuel cool the injector ?
Yes
So reducing temp will cool more ?
Yes
debate here"
Can you reduce the temperature of the fuel?
Yes
How much does the valve cover radient heat management effect this?
"Insert data, scientific publication/evidence"

To what extent does temperature changes effect optimal performance on GDI assuming fuel type, pressure and GDI design?
"Insert scientific based publications "

I think the broader debate is fuel cooling. Looks like we have annecdotal evidence from OEM and perofrmance aftermarket designs for active cooling. Valve cover could be assumed a less effective method but, perhaps it has some contribution as yet unproven?

Marty,
For high pressure systems , there are many Diesel high pressure fuel systems with aircon fuel coolers it turns out like the merc one. Some of these operate at 13,000+ psi even , so higher again. I couldnt see if it was pre-high pressure fuel pump though .Which I think might be the right strategy too to help pump longevity and performance. I know electric pumps dont like being really hot in terms of efficiency so maybe taking heat load out of our pumps might be a good thing too.
 

matreyia

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So I changed my mind, live with it and will post anything I like unless asked by the moderator not to.

I know exactly how the system works and since fixed the heat issues.

I wont be sharing it or any future development with the community.

Most vendors stopped sharing ideas and development and moved on to other platforms as its not worth the headache and cheap chinese knock offs.

What new products have you seen or any development done for the n54 lately that pushes this platform forward, let me answer it for you very little to none.

There is lot more places this platform can improve too bad it most likely will never happen thanks to people like yourself

Dude, fuck all those armchair engineer assholes. Keep sharing your ideas.
If anyone doesn't understand that hot metal heats up air, which heats up metal lines, which heats up fuel...then fuck them. Sure it's a small amount, but there is a saying: "EVERYTHING COUNTS IN LARGE AMOUNTS". And eventually, each small amount of heat avoided will become a large enough amount to matter.

So tired of all these fools always talking shit that is obviously against physics. They like to say, "how did you measure?...blah blah..." Shit man, you don't need to literally measure the fuel inside a metal rail to know that the fuel will be exposed to higher temperatures if the metal line is exposed to higher radiant heat or contact heat. How much more or less is anyone's guess, but to say it doesn't make a lick of difference in temperatures is simply absurd.

Take two metal bowls of water, stick a thermometer in each, set one bowl next to a radiator heater unit, and the other one away....I guarantee you the bowl away from the radiant heater will be cooler...and even high temperature if you actually touch the radiant heater unit.
 
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The Convert

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Dude, fuck all those armchair engineer assholes. Keep sharing your ideas.
If anyone doesn't understand that hot metal heats up air, which heats up metal lines, which heats up fuel...then fuck them. Sure it's a small amount, but there is a saying: "EVERYTHING COUNTS IN LARGE AMOUNTS". And eventually, each small amount of heat avoided will become a large enough amount to matter.

So tired of all these fools always talking shit that is obviously against physics. They like to say, "how did you measure?...blah blah..." Shit man, you don't need to literally measure the fuel inside a metal rail to know that the fuel will be exposed to higher temperatures if the metal line is exposed to higher radiant heat or contact heat. How much more or less is anyone's guess, but to say it doesn't make a lick of difference in temperatures is simply absurd.

Take two metal bowls of water, stick a thermometer in each, set one bowl next to a radiator heater unit, and the other one away....I guarantee you the bowl away from the radiant heater will be cooler...and even high temperature if you actually touch the radiant heater unit.
Just to give you a little physics lesson, air is an insulator, not a conductor. That means it will prohibit heat transfer more than it will inhibit heat transfer.

Edit to include comments on your bowl scenario.

The two bowls of water will be the same temperature given neither is in physical contact with the radiator itself. They’ll reach equilibrium in the room given a constant temp out of the radiator. The reason a room can be comfortable and a radiator scalding to the touch is because air is a poor conductor.
 
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fmorelli

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So tired of all these fools always talking shit that is obviously against physics. They like to say, "how did you measure?...blah blah..." Shit man, you don't need to literally measure the fuel inside a metal rail to know that the fuel will be exposed to higher temperatures if the metal line is exposed to higher radiant heat or contact heat. How much more or less is anyone's guess, but to say it doesn't make a lick of difference in temperatures is simply absurd.
This comment is inscrutable. As is your bowl example which I did not include. Fuel is moving through the rail: it's not a static body coming to temperature equilibrium. How much the fuel actually gets heated (or not) matters - that's the point of the whole thing! If that's "anyone's guess" ... then ... Q.E.D.

Filippo
 
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matreyia

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This comment is inscrutable. As is your bowl example which I did not include. Fuel is moving through the rail: it's not a static body coming to temperature equilibrium. How much the fuel actually gets heated (or not) matters - that's the point of the whole thing! If that's "anyone's guess" ... then ... Q.E.D.

Filippo

You're saying moving fuel isn't affected by ambient temperatures through a metal tube... which is wrong. It is affected, it may not be enough to matter, but it is affected unless you live in a universe where thermodynamics stopped working.
 

The Convert

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You're saying moving fuel isn't affected by ambient temperatures through a metal tube... which is wrong. It is affected, it may not be enough to matter, but it is affected unless you live in a universe where thermodynamics stopped working.
You need to do two things:
1) stop insulting people.
2) stop throwing around words you don’t understand.

Go find the heat transfer coefficient for fuel, the mass of fuel in the rail at any given point in time, how long the fuel is actually in the rail at any given point in time, and figure out what the max rail temp is with and without the phenolic gaskets. That should get you started on determining what the actual delta T is of the fuel exiting the rail into the injector.
 

fmorelli

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You're saying moving fuel isn't affected by ambient temperatures through a metal tube... which is wrong. It is affected, it may not be enough to matter, but it is affected unless you live in a universe where thermodynamics stopped working.
Let me help you out. Don't tell me what I'm saying. That's what you are saying (you misunderstood).

Filippo
 

Torgus

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How the fuck does an argument over $0.60 worth of washers turn into an engineering and scientific shitshow?


Oh that's right, just N54 things.
FFS

FFS at least know what you are talking about mate ;)

Please reread the 1st page: https://www.spoolstreet.com/threads/how-can-a-valve-cover-heat-up-fuel-lines.6140/

@martymil claimed the M18 VC was a bad design because of the fuel rail indent design and that the VTT's VC product was better designed because of this and is what people should buy. The claim was the M18 VC heated up the fuel lines more than the VTT product. He was just shilling for VTT as this is the most ridiculous thing ever. I explained the fuel lines and rail are connected directly to the injectors, cylinders, block, etc which is why a VC's design has no effect on the fuel temp injected into the cylinder because of fuel rail indents on a VC. Especially as air is a great insulator and the volume of fuel going through the fuel lines at WOT there is no time for the fuel to heat up in a meaningful way. You can look up the math above.

This is not a discussion about washers. It is about VC design and how it in no way affects the fuel rail temperature in a meaningful way. Trying to keep people on topic is like herding cats.
 
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matreyia

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Let me help you out. Don't tell me what I'm saying. That's what you are saying (you misunderstood).

Filippo

OK, you're saying this: "Fuel is moving through the rail: it's not a static body coming to temperature equilibrium."
And I'm saying moving fuel may be at different rates than static fuel but it still is affected by thermal differential.
 

The Convert

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OK, you're saying this: "Fuel is moving through the rail: it's not a static body coming to temperature equilibrium."
And I'm saying moving fuel may be at different rates than static fuel but it still is affected by thermal differential.
And we’re telling you that any difference would be unmeasurable in any meaningful way. It would translate to nothing performance/drive ability wise. Even if you just idled the car for ages, you’d cycle fuel through too quickly for it to matter.

That is not to say don’t do it though. It costs more in time than money. So, it’s really just a personal choice thing. Just don’t try to tell me people it changed aspects of your car.
 
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martymil

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And we’re telling you that any difference would be unmeasurable in any meaningful way. It would translate to nothing performance/drive ability wise. Even if you just idled the car for ages, you’d cycle fuel through too quickly for it to matter.

That is not to say don’t do it though. It costs more in time than money. So, it’s really just a personal choice thing. Just don’t try to tell me people it changed aspects of your car.

You are wrong period, making a blanket statement like this.

Unmeasurable ?

Seen over 100f swings from idle to full throttle swings.

There is no thermal radiant transfer ?

There is even thermal transfer on the VTT cover and that's why we ceramic coated ours and even the
fuel rail is ceramic coated.

There is no performance gain, definitely dead wrong but you spend the money and do the testing because I definitely wont be sharing it.

At the end of the day buy what ever VC you want its like buying Michelin PS3 vs PS4s and saying there is no performance benefit.
 

The Convert

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And we’re telling you that any difference would be unmeasurable in any meaningful way. It would translate to nothing performance/drive ability wise. Even if you just idled the car for ages, you’d cycle fuel through too quickly for it to matter.
You are wrong period, making a blanket statement like this.

Unmeasurable ?

Seen over 100f swings from idle to full throttle swings.

There is no thermal radiant transfer ?

There is even thermal transfer on the VTT cover and that's why we ceramic coated ours and even the
fuel rail is ceramic coated.

There is no performance gain, definitely dead wrong but you spend the money and do the testing because I definitely wont be sharing it.

At the end of the day buy what ever VC you want its like buying Michelin PS3 vs PS4s and saying there is no performance benefit.
measuring the exterior temperature of your fuel rail with a cheap IR gun does not equate to measuring your fuel temp. Sorry, but it’s just not. If you wanted to calculate the heat transfer into the fuel based on fuel rail temp, that would certainly work, but You didn’t do that. If you did, you’d just share the math.