Would dual LP's in Paralell work?

If I installed the cummins LP kit on the frame by the tank
" T" to supply both pumps and 'T"ed the output at Filter input would I get improved flow at ~ same LP pressure?

I think I can work out the control circuits, just wondering if
a worth while experiment.

 

Short answer is, no it wont work.The only way to improve volume of either a single pump or a group of pumps,that are drawing fuel thru a suction line, is to increase the effective area of the suction line feeding the pumps.That is why Mopar put the new pump in the bottom of the tank.

 

Some of us have been running dual list pumps for a while now,, Mine is just inline with a factory lift pump,, I installed a holly pump just before the tank, And Hooked to the same Elec Circuit as the factory pump. I did mine about a year ago and still have 20psi at idle and 18psi at WOT. It has been rock solid.

Photos in my gallery.

 

Truckman---Do you have the rear pump wired directly into the front pump or do you have a relay wired into the front pump to run the back pump ?

 

Truck man, What type of pump is the Holly,
Impellar, 'G' Rotor or the 'shuttle ' type.

Reason I ask, I have 2 LP's in series on another brand truck,
both the shuttle type, Fuel can be sucked through if pump not working. Maybe that is a better way to go?

OH, No mods and no plans to do so, just want reliability..

 

holly blue triggered by relay off LP.
running from the blue up and throught stock LP.
23idle-15wot.

 

I have my pump wired (Soldered)direct to the factory LP Wiring,With No relays.

 

Truckman---Thanks for the info

 

Get dual Carters. They bolt directly to the block mount, and are THE SAME as the factory pump, but without the banjo fittings. They come with nipples. The NAPA replacement lift pump is identical except for the fittings, but costs $240. YOU MUST run a relay to control the pumps. The oe relay is in the ecm, and DOES crap out. You also MUST use a kill relay for the framerail pump with the kill signal coming from the starter wire (the small one! ) If you do not do this, you will have hard starting issues as the pressure will overcome the diaphragm in the vp. It won't hurt anything except for tiring out your starter.

Both relays can be the same as the ones under your hood, just use spade connectors and wire in a fuse for the power for the pumps. Also, the kill relay must be wired so the hot is not the switching, but the switched. Hard to explain, but if you wire it one way, when you start it and it kills the framerail pump, it will energize a unused tab on the relay causing a short hazard. Look at the little wiring diagram on the relay and you will see what I mean.

Mine is just like this except I blew it and bought a factory style replacement for the block ($140 mistake). It works great for me, but I'm only making about 350rwhp, so if you are doing more you might want a vulcan line setup or a FASS or something.

 

What is the point in having two pumps? Is it when you are worried one will go out? I am curious because any one of the pumps mentioned has far more delivery capacity than the VP44 can consume, so volume is obviously not the reason. For reliability it would seem that having a replacement spare is better since it will not be running all the time, so will not have any wear and tear on it. I guess I am confused