2nd gen piston pump

[JQmile]

Looks like I might be able to get one for cheap (or free) any problems with running it into the VE with a regulator (set at 15psi)?? Would I have to run a return line to the tank or could I just deadhead against the regulator?

thanks guys.

Jason

[DTanklage]

Would I have to run a return line to the tank or could I just deadhead against the regulator??

thanks guys.

Jason

you could just dead head to the ve but i always use a return system

dead headed it will creap ands or drop

[KTA]

Depending on your ultimate power goal it won't be able to flow enough fuel.

[cummins king]

piston pump has more fuel flowing, bigger holes

[DTanklage]

Depending on your ultimate power goal it won't be able to flow enough fuel.

you must be building him one heck of a ve

[DTanklage]

oh, i thought you meant a piston pump couldnt keep up...

you are saying that if he plumbs it with a return it wont keep up

how do you figure?

if it can keep up dead headed it can keep up with a return

[Greenleaf]

There was some debate on another web site as to the OEM 2nd gen piston pump. In terms of it's flow and HP it will support. I know enough to know that piston dia determines flow, but outsied of that I don't know about dead heading into a reg. That would make the regulator worthless, no?

Joe Donnelly said his OEM piston pump gave him 799 HP. I doubt that you'd need more than a piston pump and a proper regulator for return. The P-Pump has a pressure regulator to keep the internal psi at about 30 or so, though I have seem more and sometimes less.

Perhaps KTA is refering to high supply PSI into the VE as some have done. I don't know if you'd need more than 30-35 psi supply into the VE. Then you don't need a reg. Just use the restriction orvice on the VE outlet sized to the proper dia. for the proper internal psi and flow.

[cummins king]

well it depends on how much power he wants to make, 30 psi is good for regular driving, but hes going to ne a snap ring in the front of pump, and while hes at it he can through in a hi pressure seal, then if he wants high hp he can put 60psi to it and keep a 14mm happy

[KTA]

The stock 2nd gen lift pump is rated at .8GPM free flow @1250rpm which is 2500rpm engine speed. That means it can feed up to a 400cc pump @0psi. So a 300cc pump which is what it takes to make over 500rwhp might maintain 5psi or so at full load. Guys get away with dynoing big numbers with stock fuel pumps because it only takes like 2-3 seconds for a 700hp run on a dynojet and that isn't enough time to deplete the fuel already in the system. Take them off the rollers and put them on the track and they are making like 400hp in 10seconds because they are out of fuel.

[DTanklage]

The stock 2nd gen lift pump is rated at .8GPM free flow @1250rpm which is 2500rpm engine speed.

where did you get that number?

hear ya about the difference between dyno queen and real deal

[Greenleaf]

hear ya about the difference between dyno queen and real deal

There sure is, that is a fact.

The day I find I'll need more than 5-10 psi supply is the day I know I'm too far in over my head.

[KTA]

That number comes from the Cummins parts catalog.

[JQmile]

Why ya gotta know so much, KTA

[MunK]

Ok...... So reading this thread it sound like one should almost eliminate the OEM style lift pump completely...if you plan to use all that hp say for more than few seconds.

On my swap, I figured to fit the crew cab with 1/2 feed line to an OEM style Electric pump from some application that can handle continuous duty and not flop...looking at a few of the Walbro pumps as an example. I will most likely run a oberg before the electric pump as a "trash filter" the tattletale will be nice, and the ability to quickly clean and continue is handy.

Then I had planned to run it to the OEM filter, bypass after the oem filter and a 3/8 return line. Think this will support 400hp for as long as the Pyro says I can hold the throttle pinned? It sure would in a gasser easily.

NoRM

[KTA]

The stock fuel filter is kind of small, but otherwise it sounds fine to me.