[captnhook]

All valid questions for a generic diesel fuel system,,,,,,,,,,,,but as for the VP44 fuel system, here's the straight scoop. In the VP44 pump there are three different pressures, lift pump pressure and two of which are being fed from a central fuel bowl, which I call the" Fuel Cavity", just like a carburetor. The electric lift pump pumps fuel from the tank to the mechanical lift pump in the VP44 which in turn fills the fuel cavity and runs fuel to various places, through little channels etc. at one pressure. This is what lubricates the pump, provides cooling for the pump solenoid and computer heat sink, AND feeds the HIGH pressure mechanical pump which makes about 130 psi to fill the rotor, when the solenoid on the end of it opens, allowing 130 psi to fill the rotor and force the pistons out against the wavy ring, and then at the magic moment it closes and the pistons compress the fuel against the closed solenoid, to make an even higher pressure, high enough to pop off the injector. So the time the solenoid is actually closed, and pop off pressure is exceeded, is the time fuel flows to an injector chosen by the rotor. If the solenoid is opened by the ECM, by dropping the 12 volts to it, before all the fuel is squashed into a cylinder, the pressure drops below pop off pressure and no more fuel flows into the engine. This is how the VP44 regulates fuel delivery. We hold the solenoid closed longer with our performance boxes to get more fuel delivery, and that is what is called a "Fueling Box". So, with that being said, higher pressure into a mechanical pump makes higher pressure out, right? That is why we don't want too much pressure from the lift pump, or the high pressure pump makes so much pressure that the solenoid can't open against all that pressure and the VP pump stops fueling or starting the engine!
So, the other story of mine is, if you push more pressure through the same size pipe, more fuel flows right? Therefore you get more cooling, which is what I am looking for to make computers last longer in VP44s. Now you know why I don't want too much PRESSURE. This is the truth. My competitors want you to think you need all kinds of volume, so they can sell you a ridiculously over rated electric lift pump,,,,,,,,,,,,,,,,but here's the truth. We proved many years ago on a dyno, that our fueling box made all the horsepower we could make, by emptying the rotor of ALL the fuel available at 5 psi!!!!!!, so don't tell me you have to have a fancy high volume lift pump to make high horsepower! This is the monkey see monkey do part of our industry. The competiton is going by the rules for a P7100 fuel system, and everybody loves it. Buy more parts, right,,,,,,,,,,,more is always better right????? Now you feel pretty smart I hope!
Merry Christmas, Chip Fisher

 

[KCMODiesel]

It's not just "the competition" that calls for more pressure than 5 psi, the Service Manual also calls for more than 5 psi. That is the minimum that you're supposed to run, and the Return Valve, which helps with cooling, is set at 14 psi.

 

[Mopar1973Man]

In all of BC's talk there there was absolutely nothing about longevity?
5 PSI is taking a huge risk for damaging the diaphragm and the pump outright.

In all off BC's talk there is no talk of Bosch, Dodge or even Cummins specifications?

Even Bosch's specs state that 70% of fuel should be returned for proper cooling and lubing. The only way to do that is 14+ PSI to open the overflow valve. Even Bosch States fuel needs to be 450 HFRR or less.

In all of BC's talk there is no talk of Bosch rebuilder voiding warranty to torn diaphragms?

Because Below 10 PSI you take the risk of tearing the diaphragm and if you return a pump with torn diaphragm a Certified Bosch Rebuild will Void the warranty due to low pressure.

Also If your a Bosch VP44 Rebuilder you'll have a Bosch 815 Test stand on site... You might ask who has these test stands... I only know of a few confirmed places.

What I'm saying be smart people don't do something foolish to damage a good pump. I'm not knocking BC's abilities but some of the comments are taken the wrong way and people run serious low fuel pressure or do foolish things to damage them from mis-understanding of some of BC's comments.

 

[Jbh97009]

I don't want to stir the pot too much, but I would think with all of chip's vp expertise, he would have a Bosch 815 test bench.... Hmmm.....

 

[j-fox]

Blue Chip has fewer returns than anybody out there. He knows the VP 44 and you can believe what he says.

For those who want to run high pressures to it, or anything above 15 or so, you are actually heting the fuel needed to COOL the pump!

But, it is your truck run all the pressure you want to it.

 

[cummins6sp5.9]

Blue Chip has fewer returns than anybody out there. He knows the VP 44 and you can believe what he says.

For those who want to run high pressures to it, or anything above 15 or so, you are actually heting the fuel needed to COOL the pump!

But, it is your truck run all the pressure you want to it.

If the VP does not require fuel pressure to cool the pumps electronics and open the by pass at 14 allowing that 70% to return the fuel back to the tank according to the designer of the VP-44 injection pump. I can assure you the nobody knows the VP any better then the designers themselves. Not to pound on B/C but a buddy installed a VP from B/C here about two weeks ago. Ran it about four days and the truck dies on him going to work. Gets a ride to work. I help him get the truck home. We scan for codes check fuel pressure check filter housing bleed the system at the head. Long story short the VP bit the dirt again in less then three weeks. He calls BC, sends it in. They call back and say the pump is shot That's OK he's got warranty right?? WRONG. BC wouldn't warranty it because of low pressure. He tells them to send him the pump. Costing him another grand. We've since got the new pump in and running. But it came from thorough Bred:thumbsup: He's done with bc's. BS. Is what I'm saying is that customer service is 100 % in my book. No c/s. No business from me.

 

[Jbh97009]

Well if the bypass doesn't open till 14 psi I guess your damed if ya do and damed if ya don't...

I'll continue to run 19psi... I bet my pump will outlast anyone running 5 psi...

 

[cummins6sp5.9]

Well if the bypass doesn't open till 14 psi I guess your damed if ya do and damed if ya don't...

I'll continue to run 19psi... I bet my pump will outlast anyone running 5 psi...

20 psi at idle for my buddy now. 20 psi for me also.:thumbsup:

 

[TxCTD0159]

lol monkey see monkey do... uhhh CUMMINS says 10psi minimum... Ill take their word along with bosch you know... the designers over any performance dudes word... seriously some people believe anything they hear... run below 10psi for very long your gonna have a shot vp. wonder why the factory lift pumps were such a problem? not supplying enough PRESSURE. VPs are the most sensitive pump of them all. dont believe everything you hear and take everything with a grain of salt...

 

[KATOOM]

Wow..... I wouldn't have thought that I'd see a thread like this one ever again, but here we are once again debating something which has been hashed out for about a decade.

First off, let me just say that I like Chip. He's a nice guy that will not only take time to talk to all, but also listen to what you have to say as well. I know this because I've talked to the guy for probably over an hour of combined time on the phone. And in that time, we talked about all the stuff on his website. In saying that, I talked about other new found ideas (more than just fuel pressures) which he didn't list on his website and he was well receptive to lots of current day talk about the VP. In our discussion about what he's discovered over the years, he is obviously learning from the experience of the consumer. ie, trial and error on other peoples dimes. Thats not meant to be a bad thing either but pointing out the common ways most aftermarket companies learn. R&D is expensive.

In regards to what Moparman stated about longevity, this is truth. Even though Chip thought he proved that the VP was good down to 5psi before it started making unsafe heat, he also admitted to me that his test wasn't "real world" testing on a working truck but was on a bench under "ideal" conditions. Also, in that 5psi test, he was only determining a relative running temperature of the VP.....not longevity at that pressure. Nor did he at that time consider or include heat soaking from the engine. For anyone who's followed historical findings on VP reliability, there is more than just a couple reasons why a VP will fail..... and not just low fuel pressure.

Lastly, as many are probably mislead, Blue Chip Diesel does NOT rebuild any of their VP's. He gets them from a supplier/re-builder of his choice. Maybe one source or maybe many sources, I dont know. But you cannot re-manufacture a VP without a Bosch certification. Read his bio on their website and you'll clearly see that he made one of the first tuners for the ISB engine. It doesn't say anything about being a "certified" re-manufacture of the VP. I could be wrong about that too since Chip himself told me about his "supplier" a few years ago, so maybe by now he became certified and rebuilds them. But last time we talked, he still didn't rebuild his own pumps. And last time we talked also talked about the newer found results of running higher fuel pressures to the VP and he stated that he wasn't sure.....but couldn't ignore the positive results. :confused013: In case you didnt know either, about that time period was when BC started selling other higher pressure/higher volume fuel pumps besides the OEM replacement lift pump. I'm not sure what to say about that since it seems his opinions may not be as solid as he thought but possibly he just hasn't done any more testing since he's still selling VP's. In saying that, testing is time and money so why bother when the need for the VP decreases every year as more ISB trucks are removed from the road while people are moving on to CR systems.

Again, for my fondness of the fellow, I mentioned that I liked Chip and I respect his knowledge too, but clearly he is (or was) conflicted about fuel pressures. Obviously Bosch recognized the issue with low fuel pressure since one of the upgrades was a thicker metal covered diaphragm. Cant ignore that fact. But even with a nice strong diaphragm, heat still remains to be an issue.

Thank you for the thread. I will continue to run my fuel pressure at 19-20 psi idle and 15-16 psi WOT. :thumbsup:

 

[j-fox]

If the VP does not require fuel pressure to cool the pumps electronics and open the by pass at 14 allowing that 70% to return the fuel back to the tank according to the designer of the VP-44 injection pump. I can assure you the nobody knows the VP any better then the designers themselves. Not to pound on B/C but a buddy installed a VP from B/C here about two weeks ago. Ran it about four days and the truck dies on him going to work. Gets a ride to work. I help him get the truck home. We scan for codes check fuel pressure check filter housing bleed the system at the head. Long story short the VP bit the dirt again in less then three weeks. He calls BC, sends it in. They call back and say the pump is shot That's OK he's got warranty right?? WRONG. BC wouldn't warranty it because of low pressure. He tells them to send him the pump. Costing him another grand. We've since got the new pump in and running. But it came from thorough Bred:thumbsup: He's done with bc's. BS. Is what I'm saying is that customer service is 100 % in my book. No c/s. No business from me.

I didn't say it does NOT require pressure to cool it.
Where did you get that from my post?
Your friends warantee was denied because of a pressure issue, so what pressures did he run to it? Did you check it?
You are trying to make Chip look bad for your error.
I'm not claiming BC is perfect. They can't be with an imperfect design pump!

 

[VFI&T]

I'm curious, How did BC determine it was a pressure issue. Was the diaphram cracked?
Which I doubt the newer style are pretty stout. Were there any codes found lack of fuel could cause internal advance issue and throw a P0216 timing code. Who determined the cause of failure BC or the supplier and if it was the supplier did they try to run a comparison test and pull codes stored in PSG If so did you get a copy of the read out from the supplier?

 

[FiveNine]

Wow..... I wouldn't have thought that I'd see a thread like this one ever again, but here we are once again debating something which has been hashed out for about a decade.

First off, let me just say that I like Chip. He's a nice guy that will not only take time to talk to all, but also listen to what you have to say as well. I know this because I've talked to the guy for probably over an hour of combined time on the phone. And in that time, we talked about all the stuff on his website. In saying that, I talked about other new found ideas (more than just fuel pressures) which he didn't list on his website and he was well receptive to lots of current day talk about the VP. In our discussion about what he's discovered over the years, he is obviously learning from the experience of the consumer. ie, trial and error on other peoples dimes. Thats not meant to be a bad thing either but pointing out the common ways most aftermarket companies learn. R&D is expensive.

In regards to what Moparman stated about longevity, this is truth. Even though Chip thought he proved that the VP was good down to 5psi before it started making unsafe heat, he also admitted to me that his test wasn't "real world" testing on a working truck but was on a bench under "ideal" conditions. Also, in that 5psi test, he was only determining a relative running temperature of the VP.....not longevity at that pressure. Nor did he at that time consider or include heat soaking from the engine. For anyone who's followed historical findings on VP reliability, there is more than just a couple reasons why a VP will fail..... and not just low fuel pressure.

Lastly, as many are probably mislead, Blue Chip Diesel does NOT rebuild any of their VP's. He gets them from a supplier/re-builder of his choice. Maybe one source or maybe many sources, I dont know. But you cannot re-manufacture a VP without a Bosch certification. Read his bio on their website and you'll clearly see that he made one of the first tuners for the ISB engine. It doesn't say anything about being a "certified" re-manufacture of the VP. I could be wrong about that too since Chip himself told me about his "supplier" a few years ago, so maybe by now he became certified and rebuilds them. But last time we talked, he still didn't rebuild his own pumps. And last time we talked also talked about the newer found results of running higher fuel pressures to the VP and he stated that he wasn't sure.....but couldn't ignore the positive results. :confused013: In case you didnt know either, about that time period was when BC started selling other higher pressure/higher volume fuel pumps besides the OEM replacement lift pump. I'm not sure what to say about that since it seems his opinions may not be as solid as he thought but possibly he just hasn't done any more testing since he's still selling VP's. In saying that, testing is time and money so why bother when the need for the VP decreases every year as more ISB trucks are removed from the road while people are moving on to CR systems.

Again, for my fondness of the fellow, I mentioned that I liked Chip and I respect his knowledge too, but clearly he is (or was) conflicted about fuel pressures. Obviously Bosch recognized the issue with low fuel pressure since one of the upgrades was a thicker metal covered diaphragm. Cant ignore that fact. But even with a nice strong diaphragm, heat still remains to be an issue.

Thank you for the thread. I will continue to run my fuel pressure at 19-20 psi idle and 15-16 psi WOT. :thumbsup:

He does not rebuild his own pumps. I bought one, and asked about warranty and was told they all go threw bosch. He is just a middle man. Really nice guy, that answered all my questions and went over and beyond what any of the other venders on this site did. Well worth the extra money IMO.

 

[VFI&T]

Bosch does'nt build 5 different grades of pumps,