Hey guys, just wondering what your opinions are on optimum fuel pressure to our ve pumps. I've been researching a piston lp upgrade for a while, and from what I understand, 15 psi is great for the ve. Well, in all my searching through which pump brand, which generation pump, which piston, which spring, and all the ridiculous p/n changes, I accidentally came across this, http://www.TheHungryDiesel.com/#2513
This is definitely the one I'll order, (a true high volume, low pressure pump.) When ordering one it asks what fuel pressure ya want, 12, 15, 18. The numbers are close enough to have me wondering which one I want. I'm not planning on doing much more as far as mods, I just wanna make sure I don't ever starv my ip. Thanks guys

 

Seems to me much over 15 and you end up pushing the seal out of the front of the pump and get to pull it to put a new seal in.

You might look into the first-gen piston pump and the second-gen pump from Cummins and swapping the spring over like others here have done. They probably swapped a different spring into the 2nd-gen pump.

 

15 is the max a VE pump should be expected to hold. That being said, there's a few tricks to holding more. You can Locktite the main seal and hold a few more psi. That obviously requires pulling the pump.

My pump on the other hand has been holding 18-20 psi for three years with no problems yet. (Knock on wood) why? I don't know. I just put a gauge on last night and discovered the excess pressure

I think all most folks need is a low pressure piston pump - that should be fine for getting close to 400 Hp.

 

In your signature, I see 500K. If that is 500,000 miles I'd rebuild that pump first. Over the 15 years or so I've been reading different forums, I've read a few threads were the seal failed at pressures as low as 10psi. I would consider anything over that flirting with disaster without taking appropriate percussion. With the mild modifications I had on my 91 including 7X.010" injectors, the Delphi pump supplied all the fuel I needed and then some all the way to 3200RPM without dropping to zero psi.

 

Yes sir, that's the plan. That's exactly what he does in the link I posted, takes a genuine cummins 2nd gen lp, and installs the correct spring for ve pressure. I'm thinking I'll go with the 12psi option because the fact that it's higher volume, (big piston) insures that it's harder to draw down to low pressures with my mild mods/tweaks.
In my searching I came across quite a few threads from guys saying that their Delphi pumps were hitting 0-1psi without huge mods. I'm not gonna try it.

 

Yes sir, I agree. Pump rebuild is on the list. Right now the truck is down for a complete Dana 70 rebuild, possibly a complete getrag rebuild, gauges are on the way, aftermarket intake soon after, Front end should be rebuilt, oh and it needs tires. All this into a truck that's currently sitting on blocks and doesn't get drove in the winter. My ol' lady's , thinks I should bye new truck. She doesn't understand, and probably never will.
If I get all this done before March/April, I Will also rebuild the pump. When I first bought this truck and joined this forum, I remember you guys mentioning "the disease" or "the bug" referring to the addiction that these first gen cummins can create. You weren't kidding. Glad to be part of it. Thanks guys.

 

For that price tag I think I'd see what the two pumps from Cummins are, if it's cheaper swap the springs. Then you can swing in next time you pass the scrap yard and have enough cash for a 6-pack.

 

I wish I could say that's a good idea, and I'm not saying it's not. When I started searching, I was typing in everything I could think of, and there's about a billion threads on this topic. Most of them involved mass confusion about the correct p/n. About the time I thought I had the correct part numbers, I'd go to the next forum, and someone would say that number doesn't exist anymore, it's changed to "this" one. Or ya have to go cross reference it to this tractor dealer. I saw prices from $60-$200. The cheap ones some guys had great luck with, and others said it was no better than the stocker. I finally came up with with a cummins low pressure piston pump with the small piston and bronze sleeve, a spacer, two gaskets, and the fuel line for about $240. So then I started investigating what it would take to modify the second gen pump to get lower pressures. A lot of guys have done it, but again nobody seemed to be on the same page as far as brands, p/n's, or where to get parts. That's when I came across " the hungry diesel" website. Has exactly what I want, with no p/n, no conversions, no extra parts. Just spend $265 and bolt it on. Maybe I'm caught up in to many projects at one time, so some relief on one of em was worth a few bucks. I'm about to post some more questions on another subject. Thanks for all the input guys.

 

Get the hungry diesel pump with 12psi spring.

The cummins pumps aren't much cheaper and they don't have the volume or options in springs.

I used a cummins lp piston pump first and it was no better pressure wise than the stock diaphragm pump. I then bought a second gen high pressure pump and used my spring from the lp piston pump and shimmed it up to get 11psi at idle. Had the hungry diesel pump been available at the time I would have went that route, much easier.

 

x2 woke my truck right up,have never dropped lower than 8.5 psi pulling 18k with that pump.