[dodgetank98]

i installed a DDRP on my 98 and i am happy with it! everyone was telling me i wont like it because it wont give me good pressure and all that but.... i have news i never have any less then about 11 psi and at idle i am at about 22-23 psi.. so anyone who wants to do it... it works just fine..:thumbsup: oh and here is some proof

 

[Whippit96]

Pressure over 20psi is not good for the VP44...you may want to try and lower the pressure a bit.

 

[Loco Offroad]

Pressure over 20psi is not good for the VP44...you may want to try and lower the pressure a bit.

No, cause then his crappy stock fuel system will let it drop below 10psi when hes on the throttle.

Sorry buddy but thats not a well working system, its barely ok for a stock rig.

 

[Whippit96]

No, cause then his crappy stock fuel system will let it drop below 10psi when hes on the throttle.

Sorry buddy but thats not a well working system, its barely ok for a stock rig.

I was trying to be nice.

 

[BighornSheep]

someone needs to post up a sticky about fuel pressures. 20+psi doesnt hurt the VP pump. ask Dave from Vulcan. he runs at 38 psi IIRC...

 

[Whippit96]

someone needs to post up a sticky about fuel pressures. 20+psi doesnt hurt the VP pump. ask Dave from Vulcan. he runs at 38 psi IIRC...

OMG one person says it's ok and now it's written into Cummin's law.

If the VP44 was supposed to have high pressure going into it, Bosch would state that. But they don't, So I'll stick to what works 100% of the time 10-20psi.

 

[Loco Offroad]

OMG one person says it's ok and now it's written into Cummin's law.

If the VP44 was supposed to have high pressure going into it, Bosch would state that. But they don't, So I'll stick to what works 100% of the time 10-20psi.

Lotsa guys run 20+. I have buddies with tons of miles on their 24v trucks that ran 23psi at idle for years. No biggie. I cant say it was any better for the IP than low fuel pressure would be, but it worked. The fact is, the original poster would not have sufficient fuel supply to his injection pump if he ran his ddrp any lower at idle. With a big line kit I am confident that these troubles would be over, but for now apparently it "works just fine".

One more thing.. I list my lift pump in my sig as a "FASS" because I spent the bucks to get on of the baddest pumps out there. Since when does a stock replacement ddrp constitute a "FASS"?

 

[dodgetank98]

Wow thanks for being d bags about it... it works no problems I just wanted to tell yall its not really as bad as what everyone has told me.. its better then stock and I have good fp.. and sorry I will add the ddrp.. don't want to make anyone too butt hurt.

 

[Loco Offroad]

Wow thanks for being d bags about it... it works no problems I just wanted to tell yall its not really as bad as what everyone has told me.. its better then stock and I have good fp.. and sorry I will add the ddrp.. don't want to make anyone too butt hurt.

Didnt mean it like that at all.. Just time to clarify things around here.. Theres a lot of the blind leading the blind. Just because somebody says something doesnt make it true, but everyone else will repeat it even if it doesnt make sense.

In my defense, your fuel pressure is "fine". Good job on getting decent pressure on a budget, but you might want to look into an upgrade of the rest of the system when money allows.

 

[dodgetank98]

ya i wasn't saying that to you its all good just other people that want to talk s when they don't have a place

 

[Whippit96]

ya i wasn't saying that to you its all good just other people that want to talk s when they don't have a place

Then who are you talking about?

 

[dodgetank98]

just forget about it its not important i was just stating my results i will leave it at that.. but where would i find this information that over 20 psi is too much pressure? and why would they make a pump that does this if it is so bad?

 

[jigabop]

its in the service repair manuals for the cummins vp44 engines. input pressure its rated for is 10-20psi. ask mopar1973man and he will post some pictures from the manual..
(btw i've also ran [email protected] idle before with stacked pumps but I made sure to change it after a while of doing that...there is a possibility of tearing the diaphragm inside the pump at higher pressures)

 

[Loco Offroad]

just forget about it its not important i was just stating my results i will leave it at that.. but where would i find this information that over 20 psi is too much pressure? and why would they make a pump that does this if it is so bad?

Its in the service manual. Ive seen it many times before.

They make a pump that goes over 20psi..... Well just because your truck doesnt need it, doesnt mean that other diesel pickups dont. 12V trucks use almost 40 if Im not mistaken, and powerstrokes I think are closer to 60. :thumbsup:

 

[Whippit96]

Thanks for answering his question guys I have been busy with work and couldn't get on here a whole lot the last two days.

 

[Fishin2Deep4U]

OMG one person says it's ok and now it's written into Cummin's law.

If the VP44 was supposed to have high pressure going into it, Bosch would state that. But they don't, So I'll stick to what works 100% of the time 10-20psi.

One thing I cannot do is rewrite Cummins Law.

What works for me may not work for you. But it does work for me. For several years, thousands of miles and also many, many more miles in the rigs I have helped swap over. BTW, they don't want to change Cummins Law either.

Bosch does not state anything regarding fuel pressures in our application. Anywhere.

I always contend that low fuel pressures are far more of a concern for me than high pressures. But oddly enough, you do not hear about high fuel pressure related failures. I wonder why?

But the rule to stay at or below 20psi comes from the inherent hard starts that could be caused by that pressure prior to cranking. It's even more rare of an issue now that we have seen most of the stock pumps move to at least one rebuilt unit.

But I am always eager to hear what the Cummins Law "interpreters" have to say.

Dave

 

[Fishin2Deep4U]

i installed a DDRP on my 98 and i am happy with it! everyone was telling me i wont like it because it wont give me good pressure and all that but.... i have news i never have any less then about 11 psi and at idle i am at about 22-23 psi..

It's hit and miss. Most guys running a small box like an EZ or the like only can get away with it. We have found that fuel pressures will be much better if you relocate the pump, change to a minimum 3/8" line size and run a DrawStraw.

This will not necessary increase your peak pressures, but will help the pump not drop as many psi under WOT conditions.

Dave