Stock Lift Pump Info

[Jetpilot]

Ok here are some pressure readings with the stock lift pump and my mods.



Idle 11 psi

1000 rpm level driving surface steady speed 9-10 psi.

1700 rpm level driving surface steady speed 3-4 psi.

WOT injectors only (box turned off) 0 psi in 2-3seconds.

WOT everything on 0 psi in less than 1 second.



I think that this just goes to show how inadequate the OEM pump is even for a stock truck... . Now for anybody who has any mods watch out



I will be installing a Mallory 4140M along with the 3140 pre-filter as soon as my hand is outta this cast (broke it Wed. night) Currently I am working on a setup that will use 2 Mallory pumps, one prefilter, 2 lines to the OEM fuel filter with one way checkvalves. This setup will allow for plenty of fuel to reach the VP44 even with a single pump failure. I will post as soon as I get it on and evaluated!

 

[Mopar-muscle]

jetpilot , what does your fuel system consist of presently ? i'm not surprised to see it go to 0 so fast , if its how i think you have it . did the truck stumble or seem like it ran out of fuel ?



when bill k installed supermentals in his truck he saw a decrease in fuel returning to the tank , the fuel going back to the tank never went lower when he/we tested it with dd2's and the hot PE turned on or off ...



your fuel system should have been maximized before install of the supermentals ... one of the reasons DD won't just sell them to anyone and you had to aquire them thru a back door i believe .

 

[Jetpilot]

John,



You are correct about the system upgrade... I just wanted to post the info for anyone interested. I was also curious myself as to what the actual #'s were. As stated I am upgrading system asap, just need two hands to get it done. I never thought the stock system would be adequate.



Doug

 

[JR2]

If that were my truck I would drive it real gently till you get the entire fuel system up to par with the rest of your mods. If not you are going to be buying a new VP44 soon.







JR

 

[HeberRam]

It's already gone!!!

Jetpilot... I have the same set-up as you with the stock lift pump. . Idle 11psi, 2000RPM 9-10psi WOT 3-6psi... I think your pump is out already... Change it quick first... before putting in second pump! You are on the verge of losing your injection pump!

 

[Jetpilot]

Thanks guys... . I plan on getting the fuel system done this week (if I can manage on one hand). I knew when the injectors went in that it would tax the stock system, but I wanted to have a baseline and to pass it along to everyone. Right now it is not being driven till the mods are done!



As for a two pump system in parallel I will let all know how/if it turns out.