how much are you supposed to open up the restriction in the return...

[Don Tanklage]

when you turn the pump up way up???



thank you



don

 

[Don Tanklage]

that much huh... .

 

[Greenleaf]

As DP mentioned, not everyone will tell all. I know it sounds dumb, but if everything was easy and simple, 1000's of $$$ woudn't have been invested in R&D.







GL

 

[DValentine]

I don't know that GL has and "records" for you to take. I do know that he has put a serious study on the internal workings of the VE pump.

 

[dpuckett]

so rather than saying "run a . 028 drill thru it and you will be okay" you would rather let me drive around with the pump turned up and "dangerously" high pressures in the ve?

They did it, too, at one point or another. It is called research, and sometimes one stumbles on a good combination that works well the first time; sometimes, it takes lots of trial and error. That is why pumps from Piers, Scheids, et al, cost $1000+ for a performance rebuilt pump- they have put the time and effort into finding what works, and the prices are an effort to try to recoup the cost of that R&D.



Some people are working hard to top 500hp on the cheap. Others take the surefire way, and top 600, but are willing to pay top dollar for it. I can understand both sides of the coin. Information is not free; never has been, never will be. If someone shares a "trade secret," one should be gracious and thankful about it, and not want more, more, more. Why should a select few do all the work, break all the parts, and the rest of us benefit from THEIR work, time, and effort, along with the big risk they are taking when they test a theory, without us putting in similar time and/or money? If you get to 750hp, feel free to share with us how you did it, though something tells me you will feel differently when you get to that point.

DP

 

[cerberusiam]

Don, sit down, take a breath, and cool off for a minute.



There are many reasons why none will just post a number and claim it will work. There are a lot of factors to take into consideration when you start customizing a pump. It is not one size fits all. What works for one may not or will not work for another and nobody wants to be on the hook for bad advice that trashes $1200 pump.



All of us are willing to help out with opinions and ideas but the best way to learn it is to do it. Try something and see if it works. Make an educated guess and post a concise description about what you hope to accomplish and I will guarantee several will chime in with other ideas or experiences that will help.



Scott is right in pointing out that a lot of R&D work is not going to be given away free. Is it right? Is it wrong? Its just the way it is. We will all share but we ain't doing it for you and we ain't gonna steer you wrong.



Here is a question that is an excellent place to start looking for the answer.



What is the ratio of return fuel to injected fuel in a stock pump at max delivery?

 

[Don Tanklage]

What is the ratio of return fuel to injected fuel in a stock pump at max delivery?

i dont know allen



dont know where to find the answer either...



even if i did know where to find the answer i would have to ask - by 'max delivery' do you mean a pump that is turned all the way up, or are you talking about a 190hp pump @ wot?

 

[dpuckett]

Max delivery- the maximum fuel that particular pump with its particular settings will deliver. I. E. max dleivery on my pump would be ~160mm/ stroke. Max delivery on a stock pump would be 74mm IC; 78mm nonIC.



Also, in our hypothetical pump, I would assume we are running stock injectors, too?

DP

 

[Don Tanklage]

isnt mm a length measurement?



i dont see how they get a measurement of 160mm...



that is over 6"



arent we looking for a fluid meas?





the stock return orfice is . 018"



cross sectional area of a 018 hole is . 000254"



if you put 10 psi of ulsdf behind a orfice of that size how much volume will flow thru that orfice?



if you put 10,000 psi how much?



that is what i am wondering



i cant remember the formulas for that stuff...

 

[cerberusiam]

Max delivery- the maximum fuel that particular pump with its particular settings will deliver. I. E. max dleivery on my pump would be ~160mm/ stroke. Max delivery on a stock pump would be 74mm IC; 78mm nonIC.



Also, in our hypothetical pump, I would assume we are running stock injectors, too?

DP

So at 160 mm per stroke on a 10mm piston you would convert that to cc's to get a number that can be used for volume. 300 cc's per stroke is capable of generating roughly 500 hp at ~ 3200 rpm.



Too lazy to do the math right now. :-laf

 

[Don Tanklage]

10/2=5



5x5=25



25x3. 14159=78. 53975



x160=12. 56636 cc's



i moved the dec over 3 places cuz that is how i do it when i am figuring out the displacement of a motor



is that not correct?



4 cyl kz 1000 (they are actually 1015 cc's, says so on cyl)



70 bore/66mm stroke



70/2=35x2=1225x3. 14159=3848. 4477x66=253997. 54x4=1015990. 1



why do i have to move the dec 3 places?



don

 

[Don Tanklage]

also, how can the stroke be 160mm???



that is almost 4"



i dont get it

 

[dpuckett]

It's supposed to be 160 CUBIC mm. I thought that was a given, as there is no way to put the 3 for cubed in normal text.



"160mm/ stroke" is 160 cubic mm PER stroke. Sorry for any confusion.



DP

 

[Don Tanklage]

still confused



cerby was talkin about 160mm stroke and 10 mm piston





why do i have to move that dec????

 

[Don Tanklage]

i guess this is why i have to move the dec:



Metric term * Abbreviation * Metric equivalent * English system



1 cubic centimeter * cm3 or cc * 1,000 cubic mm * 0. 0610 cubic in

 

[cerberusiam]

It's supposed to be 160 CUBIC mm. I thought that was a given, as there is no way to put the 3 for cubed in normal text.



"160mm/ stroke" is 160 cubic mm PER stroke. Sorry for any confusion.



DP

Somthin' still not working here, or my memory is playing tricks on me.



160 Cubic mm = . 16 cc's





Granted our engines are the most economical but that is a bit on the light side don't you think?

 

[dpuckett]

When a pump is set to "x" cc's, it is properly noted as "x" cc per 1000 strokes. Look on your (or any Cummins) engine data tag- stock fuel rate is in mm3 or cubic millimeters. Some p-pumps can pump 1000-1200mm per stroke, or 1-1. 2cc/ stroke.



Look at the cam plate, the 12mm head, and do the math. It is impossible to pump 160cc per stroke. That is over a deciliter, or 3oz!!!!! Talk about over fuelling.



and I though I was bad at math.



DP

 

[Don Tanklage]

thnx daniel



so a turned up 250mm pump is putting out a whopping 1/4 of a cc per stroke



times 6



and at least a small part of that does not get injected but is returned to the tank instead



no wonder the return at the top of the pump has a . 00025 cross sectional area



they dont want anything to come out of the damn thing!



rofl



my regulator is here, i'll get the fittings tomorrow and throw it on there



(right now my inlet pressure is 22 psi at idle and i really doubt it needs that much)



good night everyone

 

[dpuckett]

Yup, you got it right, Don. I think most of the fuel gets returned to the tank or pump. Not sure on the percentage, but I'd think it'd be 50% or more, even under full load.



Go back to e=mc (squared). Little matter, mucho energy.



DP

 

[Greenleaf]

The Sigma Pump installed on the CAT3206 pulling engine I am connected with building is currently rated for 1. 6cc/stroke w/16mm plungers. The Bosch P just could not keep up.