Scrap your P7100 and CP3's, no injection pump required for this puller...

GOT-Torque

GOT-Torque

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Have a wild idea and need some feedback on how ridiculous this is...

The following would be for an all out pulling truck...

Lets pretend the truck is spinning 5000 rpm at full load and makes 1200 hp on a dyno...

My 305 hp rated engine says 113mm^3 per stroke on the cover (engine hp). So if I scale this up to 1400 hp (engine hp) to get roughly 1200 hp to the ground, I come up with 518mm^3 per stroke.

In a sled pull of roungly 12 secs (going from memory), at around 5000 rpm, this would equate to how much fuel getting used per cylinder?

5000/60 = 83.33 revs/sec of the crankshaft
83.33/2 = 41.67 fuel injection events per cylinder per sec
41.67*518 = 21583 mm^3 of fuel per cylinder per sec
21583 mm^3 = 21.583 cm^3 = 0.021583 L = (0.0057 gal) of fuel per cylinder per sec
0.0057 * 12 = 0.0684 gal per cylinder per run
or 0.0684 * 6 = 0.41 gal for all 6 cylinders per run

Sound ok so far? I suppose at this hp level, the fuel burn is very inefficeint so I may need more fuel, so lets bump the numbers up to 0.1 gallons per cylinder per run and 0.6 gallons for all 6 cyl per run.

After reading some other posts regarding volumn and pressure differences between the P7100 and twin cp3's.

Would it be feasable to build your own fuel system for a common rail? Injectors are just a check valve (told to open and close with an electronic signal right). If you have a large enough fuel rail (apparently only 0.1 gallons per cylinder) for each individual injector and a way to maintain a high pressure on each fuel rail (like 18,000 psi), you wouldn't even need cp3's?

Have 6 high strength bottles made with nitrogen pressure on one side of a piston and diesel on the other. Vary the amount of surface area on either side to get the pressure you need. For ex. four times the area on the nitrogen side would mean only 4500 psi nitrogen to get 18,000 psi of diesel. (you get the idea).

I would think this would produce consistent, repeatable, dependable fuel flow to each cylinder. No worries of draining rail pressure, no timing of pumps, no rebuilding of pumps, no hp lost driving the fuel pump.

What do you think? Do I think about diesel crap too much or what...:bang
 
GOT-Torque said:
Have a wild idea and need some feedback on how ridiculous this is...

The following would be for an all out pulling truck...

Lets pretend the truck is spinning 5000 rpm at full load and makes 1200 hp on a dyno...

My 305 hp rated engine says 113mm^3 per stroke on the cover (engine hp). So if I scale this up to 1400 hp (engine hp) to get roughly 1200 hp to the ground, I come up with 518mm^3 per stroke.

In a sled pull of roungly 12 secs (going from memory), at around 5000 rpm, this would equate to how much fuel getting used per cylinder?

5000/60 = 83.33 revs/sec of the crankshaft
83.33/2 = 41.67 fuel injection events per cylinder per sec
41.67*518 = 21583 mm^3 of fuel per cylinder per sec
21583 mm^3 = 21.583 cm^3 = 0.021583 L = (0.0057 gal) of fuel per cylinder per sec
0.0057 * 12 = 0.0684 gal per cylinder per run
or 0.0684 * 6 = 0.41 gal for all 6 cylinders per run

Sound ok so far? I suppose at this hp level, the fuel burn is very inefficeint so I may need more fuel, so lets bump the numbers up to 0.1 gallons per cylinder per run and 0.6 gallons for all 6 cyl per run.

After reading some other posts regarding volumn and pressure differences between the P7100 and twin cp3's.

Would it be feasable to build your own fuel system for a common rail? Injectors are just a check valve (told to open and close with an electronic signal right). If you have a large enough fuel rail (apparently only 0.1 gallons per cylinder) for each individual injector and a way to maintain a high pressure on each fuel rail (like 18,000 psi), you wouldn't even need cp3's?

Have 6 high strength bottles made with nitrogen pressure on one side of a piston and diesel on the other. Vary the amount of surface area on either side to get the pressure you need. For ex. four times the area on the nitrogen side would mean only 4500 psi nitrogen to get 18,000 psi of diesel. (you get the idea).

I would think this would produce consistent, repeatable, dependable fuel flow to each cylinder. No worries of draining rail pressure, no timing of pumps, no rebuilding of pumps, no hp lost driving the fuel pump.

What do you think? Do I think about diesel crap too much or what...:bang
Click to expand...

We are talking a dedicated rig, right? Bump that pressure to 21800psi and you may have something there.
 
well at least someone is thinking outside the box.:Cheer:
 
..........and then you drill a hole deep into the asteroid, drop the nucular device in the hole, get in your space ship a take off.

Actually I like the way you think. Great use of math. Not sure on the numbers, but thats some thinkin' right there.
 
Yes, this would be for a dedicated puller only.

At work we use nitrogen tanks just as I described above (pressurized at 1500 psi, max 2000 psi) only with water on one side instead of the diesel. These are used to shut down the plant in a matter of seconds (nuclear plant), they force the control rods all the way into the reactor to absorb the neutrons (end the chain reactions). Enough talking about my work, back to the interesting diesel stuff...
 
GOT-Torque said:
Yes, this would be for a dedicated puller only.

At work we use nitrogen tanks just as I described above (pressurized at 1500 psi, max 2000 psi) only with water on one side instead of the diesel. These are used to shut down the plant in a matter of seconds (nuclear plant), they force the control rods all the way into the reactor to absorb the neutrons (end the chain reactions). Enough talking about my work, back to the interesting diesel stuff...
Click to expand...

But the talk of your work explains the calculative reasoning.
Yur like one o' dem rocket scientist
 
If I could just get enough uranium put together to fuel my homemade reactor for the pullin truck, I'm really gonna clean up at the pulls next year...:hehe:

Snedge, I see in your avatar you also have the new valve reflective coating on your pistons...
 
SOund theory...I had the good idea to inject pure oxygen into the intake stream instead of nitrous--won't put the fire out no matter how much you use--but I got the idea trashed after my boss said he didn't think our life insurance policy had a "death by gaseous explosion" clause LOL
 
Very good thought but sounds like it leaves very little room for error. In sledpulling very rarely do things work the way they should! I think this injection theory would be better for drag racing where you are running a little more consistant. In sledpulling you never know how long you will be pulling, how heavy the sled is, how much traction you'll get etc etc.
 
Keeping constant pressure through the entire stroke/canister would also be a little difficult.

If you are talking about all out performance, you would, also, probably want to have 28 to 30,000 psi of fuel pressure. Way better atomization than at 21k or 18k.

You might want to leave yourself some room to idle and warm up, get hooked up, driving off the track and getting unhooked after you just put a a$$wooping on everyone.

Certainly out of the box thinking.
 
Well, it's not nuts, all you're suggesting is the concept of providing an "infinite" fuel reservoir for a short duration. How you actually achieve it in practice would take thought and money, but all you're saying you need, is a 30k psi accumulator with about a gallon in it.

You've solved that side, now all you need to do is figure out how big the CR injector needs to be opened up to flow 4-5X the quantity they can currently pass.

Conceptually, I think you have it. Now go and do!
 
Ummm, sounds good in theory, but wouldn't you still need to warm the engine up to get complete combustion? You'd need to run a lot longer than 12 seconds to get hoooked up, lined up and make the pull.

then again, I know nothing about pulling nor pulling engines.

George
 
What if you run the CP3 while its warming up and getting to the sled, then switch it to your bottle injection and then back when you get stopped at the end? Probably complicated but then you wouldnt have to worry about the tank going dry or losing pressure.
 
I certainly like it when people think out side of the box and it might work, but how do you plan on regulating the injection cycle. If you can come up with a computer and program to do that I say Kick some a__. Keep thinking outside the box it was interesting
 
DONK78 said:
but how do you plan on regulating the injection cycle.
Click to expand...

He beat me to it. That was my only question. I was thinking about it on the way to work this morning.
 
wildmanben said:
What if you run the CP3 while its warming up and getting to the sled, then switch it to your bottle injection and then back when you get stopped at the end? Probably complicated but then you wouldnt have to worry about the tank going dry or losing pressure.
Click to expand...


beat me to that idea...

and my only other question would be: wouldn't the reservoir for diesel need to be much larger?
...explanation...as you use the diesel fuel in the reservoir, the nitrogen side of the canister/plunger would be allowed to expand...and slowly lose the pressure originally achieved...

i would think if the reservoir size were increased to compensate for the pressure loss, it would be more effective and more consistent...$.02


once again, props on the outside the box thinking :rockwoot: ...one of my old bosses was trying to get me to try a simple hydrogen injection system on my old 24 valve...outside the box thinking, and if it could be made functional would be an easy way to retire early...:ft:
 
5000/60 = 83.33 revs/sec of the crankshaft
83.33/2 = 41.67 fuel injection events per cylinder per sec
41.67*518 = 21583 mm^3 of fuel per cylinder per sec
21583 mm^3 = 21.583 cm^3 = 0.021583 L = (0.0057 gal) of fuel per cylinder per sec
0.0057 * 12 = 0.0684 gal per cylinder per run
or 0.0684 * 6 = 0.41 gal for all 6 cylinders per run


Something doesn't seem right? Are you saying that it takes less than a 1/2 gallon of fuel to pull the sled?
 
DONK78 said:
I certainly like it when people think out side of the box and it might work, but how do you plan on regulating the injection cycle. If you can come up with a computer and program to do that I say Kick some a__. Keep thinking outside the box it was interesting
Click to expand...

It would only work with CR injection, and yes the accumulator would have to have a means of not losing pressure as the 1/2 gallon is consumed. There's a few ways to do that.
 
Burner said:
Something doesn't seem right? Are you saying that it takes less than a 1/2 gallon of fuel to pull the sled?
Click to expand...

I don't think this is accurate either? But the numbers work out. I basically took the rating off the cover for a 305 hp engine (which it burns completely - no smoke) and scaled it up. I suppose since most big hp engines really roll the smoke that it is much more inefficeint and may be more like twice that number???

I completely forgot about bringing the engine up to temp... I suppose you could use one of those diesel powered block heaters to bring it up to operating temp long before the pull started (they are only about $600), pretty easy to install. Running a stock CP3 for any reason would require more injection lines (check valves rated for very high pressure), a stock engine control module, and what would you do with the CP3's fuel during the run (it would still be pumping?).

I was thinking you would write your own software control program to run on a laptop to control the injectors. (Kind of like what EFI Live does for the Duramaxes).

As someone mentioned above, the nitrogen side of the bottle would have to be big enough to maintain pressure while it expanded. You could tie all six little bottles (with the bladder and fuel in the other sides) into one big bottle in the bed with more volume. It all comes down to the ideal gas law pV=nRT where nRT would be constant for a specific volumn tank. So for what ever % volume would increase, pressure would have to decrease by the same %. This could be offset or accounted for in the software to control injection pulse width. This setup would also ensure all 6 bottles received the same pressure.

If you got really serious about it, you could heat the bottle with an electric blanket during the pass to cause the nitrogen to expand just enough to offset the loss of volume (this would mean it maintains constant pressure).

It doesn't cost anything to think, but man would this be an expensive project. If it worked though, it would certainly be :banned:

If I just had a few sponsors.........................
 
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