Anything new with the p-pump conversion injectors?

[RCP Diesel]

correct me if im wrong, but he can use the specific installed height in both instances, because he's explaining that the spring rate in both springs are very similar, so there is no need to change the spring..

also theres absolutely no mention of spring rate in any of this, thats an entire different subject that has nothing to do with seat pressures and will also effect the duration of the injector and opening/closing speeds.

 

[KILLER 'B']

also theres absolutely no mention of spring rate in any of this, thats an entire different subject that has nothing to do with seat pressures and will also effect the duration of the injector and opening/closing speeds.

12v compression spring uninstalled height 1.090" installed height 1.030" is 300BAR

24v compression spring uninstalled height 1.202" installed height 1.162" is 300BAR

12v spring creates 37lbs when compressed 0.040" and 53lbs when compressed 0.060"

24v spring creates 32lbs when compressed 0.040" and 54lbs when compressed 0.060"

he is very much so illustrating spring rate.. he is showing the springs increasing resistance as it is compressed.. this is spring rate, is it not?

the spring rates would be:
12v spring ~8lbs/ .010"
24v spring ~11lbs/ .010"

 

[Smokem]

From how I'm seeing it, the 24v spring needs to be compressed .040 to get to 300 bar and the 12v spring needs to be compressed .060 to get to 300 bar.

I said earlier, the installed heights were from the 12v holder and 24v holder, hence the difference in values. The spring rates are nearly identical, when used in the same 24v holder, they react also nearly identical.

 

[RCP Diesel]

he is very much so illustrating spring rate.. he is showing the springs increasing resistance as it is compressed.. this is spring rate, is it not?

it is assuming that the spring is being compressed the same from start to finish.

I said earlier, the installed heights were from the 12v holder and 24v holder, hence the difference in values. The spring rates are nearly identical, when used in the same 24v holder, they react also nearly identical.

so what are the numbers in a 24v holder? its completely useless to test using 12v parts in a discussion about 24v conversion injectors.

If in fact its .040 to get to 300 bar with a 12v spring in a 24v injector, just like the 24v spring then I will agree that there is no point for using the 12v spring, because the seat pressures are similar. If it takes the .060 as originally posted, the 12v spring would need to be measured at .060 and .080 and would clearly be MUCH higher.

 

[Smokem]

Let me put this in simple form, same nozzle, holder, compression pin, and intermediate disk. With the 12v spring compressed 0.070" the opening pressure is 355BAR, with the 24v spring compressed 0.070" the opening pressure is 345BAR.

 

[Soup Nazi]

The pintle does not lift that high. Most are under .025. It spends most of its time either lifting to the max lift point or returning to the closed position. A lower spring rate allows the pintle to lift to the max point faster and it also slows its return to the closed position. Rather obvious, yes? This is why we get 45% more fuel injected using measured 300 bar pulses with a 12V spring than we do with a 24v spring. This is why they idle better, run cleaner, and make more power.

WTH is this nonsense about it makes no difference? How much power do you think the pintle can generate to compress the spring? What if that pulse/slug is lazy ( comparatively speaking ) like the P7100?

Why do the new 3mm pintles used in the 6.7 injectors use a lighter set of internal parts? Do you think it has anything to do with lifting power?

All the jibber about using modified or otherwise mucked up delivery valves and other patches is wrongheaded. Do you not understand that a DV is used to remove fuel volume from the line to quickly drop the line pressure? This keeps the fuel pulses from opening the pintle after it needs to be closed.

 

[Smokem]

Oh Don, the stock pintle lifts 0.012", and the 6.7L guide is 3.5mm. So if the pintle lift is the same, and the spring rates are nearly identical, where is the grand difference?

 

[RCP Diesel]

Im going to see if I can play around with this more on Monday. Including getting real spring rates for both springs. Weston has posted up his thoughts on this. Don do you have any numbers to change things? I will post my findings when I do my testing also.

 

[Mudn_1]

Im going to see if I can play around with this more on Monday. Including getting real spring rates for both springs. Weston has posted up his thoughts on this. Don do you have any numbers to change things? I will post my findings when I do my testing also.

someone actually willing to get to the bottom of this and not just argue weston's findings!

we need more people like this......

 

[Smokem]

The points of rate I posted were from January, it was obvious then that there was no point. 5 different people can do all the tests they want, results may vary. I have made my conclusion from a few trustworthy sources, and they aren't the people to gain from selling conversion injectors...

 

[Bponci]

I don't use injectors. They are so overrated.

 

[Soup Nazi]

I seem to recall being the guy who did the conversion injectors and even posting how to do it with photos and information. Every single vendor who was approached about what to do told their customers "nothing was needed or to set the pressures lower". LOL

 

[Smokem]

I have always set them to 280-290BAR, I seem to recall you being the one to make exaggerated claims about many things. From your assumptions, you would think Bosch's methods are flawed, and far less accurate than F1 Diesel.

 

[5150ram]

This sounds like just the test for our dyno. I'll have to see if I can try the same nozzles on a p-pump truck with both springs.

 

[Stangpwr71]

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Default P-pump 24v info
The 12v injector needs 53psi seat pressure to create 300BAR, the 24v injector needs 32psi seat pressure to create 300BAR. A difference of 0.005" installed height alters the opening pressure 30BAR on the 24v injector. So, to achieve the same rate of the 12v compressioin spring, a 24v injector would need the opening pressure set to ~ 180BAR, and this would soley be a crutch. Needless to say lowering the opening pressure to the common range of 12v injectors being 260-280BAR doesn't even come close. Opening pressure can play into the power that can be made with a certain size nozzle, lowering the opening pressure can lengthen or increase duration therefore increasing the injected quantity. However, this will decrease atomization and efficiencey past a certain point. Response is often better with a higher opening pressure, which is beneficial for a street application, even though the peak number may be a bit lower.

Read more: P-pump 24v info - Diesel Bombers



Smokem does this look familiar? why the change of info now?

 

[RCP Diesel]

This just got real interesting.

 

[Stangpwr71]

I am not trying to start a fire i am just trying to get as much info as possible. I am trying to build/aquire the optimal injector for my truck.

 

[Smokem]

From the first numbers I received, that was the assumption gathered, never have I or SDX set them that low. The discrepancy came from the initial numbers taken of installed height, that I believe is where the confusion lied when Ryan questioned it. The difference in the installed height was not taken into account between the two holders. I will admit that until both springs were tested in the 24v holder, things didn't add up considering the spring rates were so closely related. I really should have followed up on this topic when I initially looked into it, but just lacked the time. Showing the rates of both springs, and the difference only being roughly 10BAR with the same amount of compression on both springs in the same holder, made everything fall in line.

 

[Smokem]

We run each injector on a test bench and measure the quantity of fuel injected along with the opening pressure. Since all the compression spring forces, nozzle pintle friction, and nozzle hole size is slightly different one cant get optimal results by setting a pop pressure alone when your working with big injectors.

The question I have about this method, why not have the nozzles balanced via Extrude Hone before installation, you would not need to comensate the opening pressure to balance injected quantity? This way you could set the opening pressure where it is desired, not where it must.

 

[Smokem]

Why do the new 3mm pintles used in the 6.7 injectors use a lighter set of internal parts? Do you think it has anything to do with lifting power?

Lifting power? The LBZ and LMM use the 3.5mm guide also, could it be to increase needle speed and to be used with the higher pressure of the later revisions to the CR system? Why on that topic, we might as well add that is why you cannot use a 6.7L nozzle on a 5.9L holder.