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CR with a P-Pump???

3K views 35 replies 15 participants last post by  Begle1 
#1 ·
my buddy and i were reading that guys are making HUGE power with a CR with a p-pump? anyone know how they set those things up? :confused013: they wernt too descriptive in the mag.
 
#5 ·
anything can be done with enough money!

the 5.9 blocks are all basically the same, minus the head/pisons/gear train. with enough time or money you can make any of them into something it originally wasnt, or make halfbreed engines with some parts of one style engine and parts of another
 
#6 ·
The idea is to keep the common rail and the electric injectors.

Only instead of feeding the rail with one or two CP3's, you use a P-pump. You tie all of the injection lines out of the injection pump together in a little rail that sits on top of the IP, then you tie that little rail into the big OEM rail.


The result is all of the flow of a P-pump, with all of the controllability of a CR.

And keep in mind, that there's no reason why you can't drive the P-pump at 1.5 or 2.0 times camshaft speed.
 
#7 ·
So then do you have to change the nozzles for the lower pressure? And who is doing the electronics to affect duration, timing, and rail pressure standards?
 
#12 ·
Im gonna go out on a limb and say thats pretty wrong.

Every P-pumped CR I have seen does NOT use the Common rail system. Why Because it wont work. But With enough money, you can get a slick running truck! Had to pull against a few this year ( 1 was a p-pumped 6.7!)

But the reason it wont work with a common rail is that a P-pump will not put out enough pressure to feed the rail. Each line going out of the pump will only squart out a small # of CC's and a certian pressure, that being the pressure of the injector pop off pressure ( usually in the 4000-4300psi range)

But a cr is running 29K PSI and that is WAY more than what a Pump pump can put out, even a 13mm or a sigma pump. They are 2 different systems that wont work together.
 
#14 ·
A CR can make huge power. They are limited to 4000rpm. Its a little more involved than doing a 2nd gen. More custom parts.

The idea is to keep the common rail and the electric injectors.

Only instead of feeding the rail with one or two CP3's, you use a P-pump. You tie all of the injection lines out of the injection pump together in a little rail that sits on top of the IP, then you tie that little rail into the big OEM rail.


The result is all of the flow of a P-pump, with all of the controllability of a CR.

And keep in mind, that there's no reason why you can't drive the P-pump at 1.5 or 2.0 times camshaft speed.
Not possible, a P7100 splits the case at high pressure. High as in 100psi.

The only advantage a ppump has anymore is that it can fuel higher rpms. With this new software comming out, the CR's will be able to stay right with them. Except the very extreme of the performance spectrum.
 
#18 ·
Not possible, a P7100 splits the case at high pressure. High as in 100psi.
Splits the case at what kind of pressure? The pump doesn't know a difference if it's pressurizing an injector or pressurizing a rail. We may be talking 4500 or so PSI in pop pressures, but the peak injection pressure is a multiple of that. And it's flowing an order of magnitude of fuel more than a CP3.


Common rails are just as limited at RPM by the CP3's inability to move fuel as they are by computer programming.
 
#16 ·
Correct, there is a rumor of a BOSCH program that will allow infinetly adjustable fueling. Like the EFI Live for the duramaxes. The thing costs 8K though.

If your swaping a CR to a Ppump to turn under 4k you are a complete idiot.

Even then, a high HP Ppump doesnt have any street manners. The valet switch just cuts around 30% of your power. 30% of 1200HP is still a handfull on the street.
 
#17 ·
Good Point.

But If you look at EFI live for D-max's, it still doesnt allow them to turn much over 4K. But there are a few D-max's out there turning past 4800....and by a Few, I know of 2 and thats it! So the P-pump will still be king, and the way the new diesels comming out look like.....it will be for a LONG time!
 
#21 ·
just listining in to get edjumacated on this here subject cause it sounds kind of crazy. going to contribute a question also. could a cp3 be used on a vp truck? or is the cps more of a full time fueling pump like a hydrolic pump and the injectors are controlled to pop off by computer? so this is really interesting. i like the idea that a p pump can keep a constant pressure like the cp3 didnt ever realize it worked that way
 
#25 ·
it still wont work!

a p-pump is putting out 4000psi through 6 orfaces, thats still going to only put the rail at 4000psi, not nearly enough pressure for the rail and what a common rail system needs to operate.

And I have personally talked with people that have swaped a massive p-pump onto their CR's, they have tried to do the p-pump into a rail....didnt work. Not only wont the rail have enough pressure, but the electronics are a nightmare!
 
#26 ·
Where did the belief that a P-pump only puts out 4000 PSI come from?

Pop pressures and peak pressures are different. A P-pump pressurizes fuel to 15,000-20,000 PSI.



You mean that somebody has actually tried this before? I fail to see how electronics would even be a factor.
 
#27 ·
Pop pressures and peak pressures are different. A P-pump pressurizes fuel to 15,000-20,000 PSI.
i'm calling shenanigans on this until you produce some proof. cause i'm with BossHawg600 i don't see what your saying working at all.
 
#30 ·
The electronics control the injectors. (though im sure some tinkering with the PCM is definately required for something like this)

You can run any pump you like as long as it can supply the fuel rail with enough pressure and flow. The rail and injectors dont know or care where the fuale comes from as long as its there!
 
#33 ·
thats almost 19,000psi for those of us that arent too good on conversions :D


Definately nothing spectacular for commonrail, but shouldnt have a problem with 19k as long as it can sustain that. I know our commonrail deere runs fine down to almost 8k on the rail! (strainer in the tank was plugged!)
 
#34 ·
Ok, Im still not following

It seems that 22-25k is what a high hp CR likes.

Why give "more" volume with less pressure just to have to fiddle with makin the electronics work on something that is still RPM limited?I still think 2 or 3 big CP3's will be right with a 14mm, even a sigma.

It seems any benefit of having more volume will be outweighed by the lower quality atomization due to the lower injection pressure.

And I seem to recall that CR injectors have a minimum PSI or they hurt themselves? I may be thinkin of the CP3.
 
#36 · (Edited)
What's piston bore and stroke on a CP3 versus piston bore and stroke on a P-pump?

A P-pump is about the same price as a CP3 and it probably is capable of flowing twice as much. It would be capable of atomizing fuel just as well as a P-pump truck does.

If it would be worth it using a P-pump to charge a rail, it'd only be worth it to a small niche. Maybe guys would be retrofitting common rails onto P-pump motors instead of P-pumps onto common rail motors.

I'm still looking for information from somebody that's actually done it, because apparently it has been done by somebody. (It's probably "that somebody" that does all of the crazy things you hear about on the Internet.)

I'd stick with multiple CP3's, personally. But I don't see why it wouldn't work.
 
#35 · (Edited)
theres a p pumped common rail in the diesel power mag., costume head and front gear tran and I believe 24v injectors. Heres a guy that sells the front gear tran. Home Page
 
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