I know there are about a gazzilion posts on this topic, but here we go again.<br><br>My sig shows my present config. I am wanting to go with bigger injectors, but want to resolve the FP problem before installing the injectors. My FP is about 14 at idle about 9 at 60 mph cruise and about 4 at WOT. If I go with injectors, I can imagine the FP will be about zip at WOT. Other than installing another stock lift pump and hoping that it's a good one, is there a proven good setup with an alternative pump? I have read about Holly black, Holly blue, etc. Is there a way to completely eliminate this wimpy, underdesigned lift pump? Gosh, this shouldn't be all that difficult considering that pumping fuel has been done since Henry Ford was a young man.<br><br>A side note.. Do you think DC will replace my existing pump under warranty with the current readings? They would probably be higher without the EZ hooked up.<br><br>(tired of this topic) [undecided]

 

Hey! I posted the following a while back, and with the resurgence of lift pump questions, I figured I'd repost it here:<br><br>Since us Canucks seem to have an even worse time of lift pump failures than our southern cousins, I took the time to pull apart 11 failed pumps that were sitting at my local Dodge dealership. In 8 cases, we discovered that the internal bypass had been well beaten, and that the pumps were kicking into a constant bypass mode, thus reducing fuel pressures to below minimum requirements. 2 of the other cases were related to bushing failure, and the 3rd was indeterminate.<br><br>Since the bypass valve was the obvious failure point in most cases, we decided (after talking with Carter and another pump manufacturer) that the long draw from the fuel tank was not causing the problem, but high outlet pressure on the lift pump was cauing the bypass to function more than it was designed to function. We then theorized that the restrictive lines/banjos from lift pump to injection pump was our problem. Techs from Carter agreed with us.<br><br>As a favor to me, the local Dodge dealer installed some high flow bolts on trucks that were seeing an inordinate number of lift pump failures. These were generally trucks used in heavy towing, and both were stock powered units. Lift pump longevity went from 20K to 80K, with no failure thus far.<br><br>We thought we had it beat, but after putting EZs and DD2's on trucks, the lift pumps began failing again. Trucks with EZs and RV275s appeared to be just fine. So, against my better judgement (pusher assemblies in ag equipment have a terrible reliability record), we tried a couple pusher assemblies using Carter pumps. Lift pump longevity seemed to be better, although pressures did begin dropping, however we ran into pusher failures in our harsh climate. The road salt and water ate the guts of the pusher pumps.<br><br>Then we switched to using Holley Black pumps, mounted in the stock location, and using 1/2 ID lines from the Black pump up to the injection pump. Last year, this worked like mad. We've got several 500 HP+ trucks, a couple with over 100,000 miles on them, and pressures are as good as the day they were installed. Again, we thought we had it beat.<br><br>Early this year, we attempted another 10 installs of Holley blacks with large lines. 8 of these installs were DOB (dead out of box). Unfortunately, after contacting Holley, we received the company line that their pumps weren't rated for diesel fuel, and as such, their warranty would not be honored. We pulled apart a couple pumps, and discovered that the internal bypass valves had some very rough edges that needed cleaning up and the bypass assemblies needed to be cleaned up with carb cleaner as the valves would stick open. After performing the procedure on a couple pumps, pressures went back to 16PSI at idle, 14 at WOT on 400HP+ trucks. But the experience with Holley has left us with a bad taste in our mouths. Two of our customers felt the same way, so they installed the Holley kits with factory lift pumps, and discovered that pressures were 16 PSI at idle, 12 WOT on their 375 HP trucks. Each has been running with this assembly on their trucks for ~20K now, and pressures have not begun to back down.<br><br>The Black changeover kits are a real bear to install on a factory lift pump equipped truck, so we found some custom 12mm to -8 fittings whose internal IDs are larger than any commercially available fittings. We're using these fittings in concert with 90 degree sweeps and -8 braided line, and feel this rigging will work well to the 375 HP mark. We don't feel that there is anywhere near enough vacuum being drawn by the factory lift at these horsepower levels to damage the pump.<br><br>For guys over the 375 mark, talks with Product Engineering out of California lead us to believe that these pumps will work great in our application. The PE pumps can draw long distances, as long as their inlet is no more than 1.5 feet above the pickup, are warrantied for 2 years in diesel fuel applications, and are simply the best built pump I've seen in a long time. We're building a bracket mount the pumps on the frame rail, under the hoodfor ease of hookup as well as protection from the elements, and the stock line size from the tank to the lift pump will be plenty large enough tosupply all the fuel the pump wants. The aforementioned -8 lines will be used to supply from lift pump to the injector pump.<br><br>Rod<br>

 

I've got the Holley Black on mine. 16 at idle and 13 at WOT with pump wire. I think I need a new few filter. Somebody on here said they stretched their spring on their Holley Blue pumps to increase the pressure. You know anything bout that Rod?

 

[quote author=BigBlue link=board=7;threadid=15893;start=0#149310 date=1055617727]<br>I've got the Holley Black on mine. 16 at idle and 13 at WOT with pump wire. I think I need a new few filter. Somebody on here said they stretched their spring on their Holley Blue pumps to increase the pressure. You know anything bout that Rod?<br>[/quote]<br><br>Stretching springs is the poor man's way of increasing the pressure on the bypass valve, however its not as good as simply buying the proper spring. I'm not sure if the Holley Blue can handle the higher pressure output (its designed for 12 PSI or so, I think?). Your pressures are excellent though, and our target for the PE systems is 15 PSI at idle and WOT, and 12 PSI throughout on the 03 system.<br><br>Rod

 

why cant u just do away with the bypass?

 

BB, PushRod: I think you are thinking about me when referring to stretching the spring. <br>I did this as a first measure when my pump did not supply sufficient pressure. When I saw that the pump was capable of delivering the pressure I swapped the spring. <br>I also had to clean and debur the piston of the pressure regulator. <br>As to my literature the blue is rated up to 20 psi, only part number that is different is the spring of the pressure regulator. (But this might be humbug from the importer ??? )<br><br>DF5152: If you do apply more than enough pressure you can beat the stock bypass valve in the VP44 to death, or even blow the seals straight out of the VP44. Hence, more pressure isn't always good. Also the stock lift pump is on a reduced duty cycle during startup to avoid a hard starting condition. <br><br>AlpineRAM

 

[quote author=AlpineRAM link=board=7;threadid=15893;start=0#149433 date=1055671660]<br><br><br>DF5152: If you do apply more than enough pressure you can beat the stock bypass valve in the VP44 to death, or even blow the seals straight out of the VP44. Hence, more pressure isn't always good. Also the stock lift pump is on a reduced duty cycle during startup to avoid a hard starting condition. <br><br>AlpineRAM<br>[/quote]<br><br>what is the purpose of the bypass valve to bleed off extra pressure? If the pump is designed to deliver X amount of pressure it will not exceed that and if for some reason it does im sure it wont for long.

 

rattle_rattle:<br><br>Rod has given you some excellent information on the &quot;pusher&quot;<br>fuel pumps available for our Dodge CTD's. I agree 100% with<br>what Rod has already told you.<br><br>My son (banshee) has a Product Engineering 4300 &quot;pusher&quot;<br>fuel pump on his 2001 Dodge CTD which is heavily modified.<br>He is right at 500 H.P. with the follwing modifications:<br>&quot;hot&quot; TST PM 3 with a &quot;piggybacked&quot; DD TTPM, Super<br>Mental Injectors, Piers Cam, Piers HX-40. Under WOT<br>his fuel pressure NEVER moves off of 16! It stays &quot;pegged&quot;<br>all the time. He bypassed the stock lift pump but left the<br>lift pump in position on the engine &quot;just in case.&quot; <br><br>His pump is one of the earlier models and he has had the <br>pump &quot;stop&quot; on him a couple of times. He has fixed this<br>by putting in a larger amp fuse which will start the pump<br>back up again. He then goes back down to the standard<br>10 AMP fuse. The &quot;experts&quot; have said that Product<br>Engineering does not think these pumps should be run<br>where there is water that will get on them (i.e. under the<br>truck). My son designed and built a custom bracket for the<br>pump which mounts on the inside of the frame rail (drivers<br>side) just to the left of the transfer case. It does not appear<br>to have much water on it but it probably is getting some.<br>The suggestion to us was to take clear silicone seal and<br>seal all the &quot;seams&quot; to the pump which we have done.<br>Rod's idea of mounting the pump under the hood is a good<br>one although I don't know if the distance from the tank will<br>be considered &quot;too far&quot; for PE's specifications on this pump.<br>As he said, Product Engineering warranties the pump for<br>two (2) years and that is about the best in the industry!<br>At this time, I feel that the PE 4300 pump is the best that<br>is out there for us. I have a complete system on the way <br>for my 2002!<br><br>Hope this has helped you some.<br><br>--------<br>John_P

 

DF5152: The pumps we have are rotary vane type pumps that will deliver a certain amount of fuel per revolution. They will do this regardless of backpressure. Now we could either design a pump that stalls at let's say 15 psi, meaning that the torque needed to turn the pump is greater than what the motor delivers, and spin up the motor with engine demand. If you bog down an electric motor ypu generate lots of heat, since nothing is moving we can't cool the coils. This pump would fall flat on it's face when the demand for fuel gets higher. <br>So, for having a simple, mass production pump, they use the same pump and incorporate a pressure regulator that will let excess pressure blow off.Usually the only part that is changed for different psi ratings of the same pump is a spring to the regulator plunger. Therefore there is much movement of fuel for the motor running on high torque equaling good cooling. <br>In an ideal world, where fluids were really incompressible, all the fuel system was made of really unelastic pipes, and where the production tolerances were nil you'd be right. <br>In our world, the system of using a regulated bypass makes sense.<br><br>Just my 2c<br><br>AlpineRAM

 

[quote author=AlpineRAM link=board=7;threadid=15893;start=0#149433 date=1055671660]<br>BB, PushRod: I think you are thinking about me when referring to stretching the spring.[/quote]<br><br> Actually, we've done this in testing from time to time as well. I think everyone whose messed with a lift pump has likely done it. Its an easy way to find out if more pressure will help in a given situation, but it does reduce the life of the spring (IMHO).<br><br>Rod

 

[quote author=DF5152 link=board=7;threadid=15893;start=0#149472 date=1055685981]
what is the purpose of the bypass valve to bleed off extra pressure? If the pump is designed to deliver X amount of pressure it will not exceed that and if for some reason it does im sure it wont for long.
[/quote]

Well, sort of. The rotary pumps are designed to deliver X amount of VOLUME per revolution at a maximum pressure, but you do have to keep in mind that our fuel system is not a free flow system. The VP44 takes fuel in &quot;gulps&quot;, and in varying amounts depending on RPM and load. The stock Carter is capable of supplying approximately twice the necessary flow (in HP applications under 400 HP), so if you eliminate the internal bypass, you're going to seriously overpressure the system. Resistance on the rotor in the lift pump will increase, and lift pump damage will occur. This is why non-internally bypassed pumps generally call for an external regulator to be used alongside them. And overpressure is bad news for the VP44 as well. It has a pressure release built into it, but its only capable of handling about 30 GPH extra.

Rod

 

[quote author=John_P link=board=7;threadid=15893;start=0#149486 date=1055688912]<br>one although I don't know if the distance from the tank will<br>be considered &quot;too far&quot; for PE's specifications on this pump.<br>[/quote]<br><br>This was one of the first questions I asked PE before we started using their pumps. PE feels that their pumps will draw 20 - 30 feet, with our fuel demands, as long as the inlet of the pump is not more than 1.5 FT above the bottom of the fuel tank. Generally speaking, a long draw from a tank, in a non-free flow situation, is not all that harmful on pumps (as long as the pump is well built). In the ag industry, you'll see electrics pulling from 20 - 30 ft away from the tank, under circumstances much more demanding than ours.<br><br>Rod

 

would the system benefit from a higher pressure pump and more GPH with an external regulator and a new bypass plumbed and then some sort of flow check valve. then the more HP u make you can just adjust your fuel as needed.

 

[quote author=DF5152 link=board=7;threadid=15893;start=0#149504 date=1055692188]
would the system benefit from a higher pressure pump and more GPH with an external regulator and a new bypass plumbed and then some sort of flow check valve. then the more HP u make you can just adjust your fuel as needed.
[/quote]

It may, although we haven't seen a HP increase with a pressure increase above 13 PSI. It seems like 13 - 15 PSI is about the right pressure, you just need to ensure enough flow at this pressure to keep everything happy. So we're sticking to the KISS principle, and simply using an internally bypassed pump with plenty of volume. With enough volume, you shouldn't need to mess with regulators to maintain pressure. We're shooting for a system that will maintain factory pressure settings at all loads and RPMs (Cummins did choose 15 PSI for a reason). We're almost there with the PE4200, however we think we'll try the 4100 next, and see what that nets us.

Rod

 

PE pumps are awesome the lowest i can pull mine is 16 psi.And there pretty to.kurt.